THE LATE JURASSICAMMONITE FAUNA OF NEW ZEALAND_1 doc

OVERSEAS CORRELATIONS Introduction Historical development Subdivision of the Tithonian Standard zones of the Kimmeridgian-Tithonian Oraka Sandstone Captain King's Shellbed, Ohinerurn For

T H E LATE J U R A S S I C A M M O N I T E

Institute of Geological & Nuclear Sciences monograph 18

(New Zealand Geological Survey paleontological bulletin 74)

Institute of Geological & Nuclear Sciences Limited

Lower Hutt, New Zealand

BIBLIOGRAPHIC REFERENCE

G R Ste\.ens

Institute of Geological & Nuclear Sciences Limited, Lower Hutt, New Zealand

Grateful acknowledgement is made to the Lottery Science Research Committee of the 'Vew Zealand Lottery Grants Board and to the Balivean Trust for financial assistance towards the publication of this monograph

Edited and prepared for publication by

Geoff Gresory Word Therapy, Paraparaumu

Printed by Graphic Press & Packaging Ltd, Levin

ISSN 11 72-028X

ISBN 0-478-09583-X

ii Cop!right Institute of Geological &Nuclear Sciences Limited 1997

Front cover: Representative New Zealand endemic ammonite taxa: Kossmatia nracnaughti n.sp (left);

Paraholiceraloides gr.ai?rmackiei n.sp (middle); Subdichotoinoceras innmetaiense n.sp (right) In the background is

a detail of the sutures exposed in specimen CE2305 Calliphylloceras empedoclis (Gemmellaro) (see Plate 4, figs 4.5)

Frontispiece: The shorelines of Kawhia Harbour, a large embayrnent on the north-westem coastline of the North Island of New Zealand, have been the prime sources of Late Jurassic ammonites since the first collec- tions by Hochstener in 1859 The illustrations show repre- sentative views ofthe south side

(middle) Nathan Point in fore- ground; Kowhai Point in mid- dle distance; in far distance: Totara Peninsula, Te Maika Peninsula and Albatross Point

(lower) Eastern shoreline of

Siltstone is exposed on the shore platform and the Mairi Ammonite Bed outcrops about half way along the coastline

Aerial photography by Lloyd Homer

ABSTRACT

Ne\\, Zealand sedimentary sequence This terrane, formed largely of volcaniclastic sediments, is interpreted as repre- senting an arc-trench system developed along the oceanward side of the Gondwana margin and separated from it by a marginal sea Most of the ammonite collections from the Murihiku have been made from the west coast of the North Island from strata of the Kawhia Regional Syncline, exposed around the shores of Kawhia and Aotea Harbours, and at Pon Waikato Marokopa and Awakino

Three ammonite localities are known from South Island strata of the Younger Torlesse (or Pahau Subterrane) The Younger Torlesse rocks are interpreted as representing the deformed contents of an accretionary prism that was devel- oped along a trench-transform system flanking the Gondwana coastline

Ye\+ Zealand Late Jurassic (Kimmeridgian and Tithonian) macrofaunas are dominated by siltstoneimudstone bivalve assemblages, with ammonites being usually in the minority Although ammonite assemblages occur at intervals throughout ihs New Zealand local stages of Heterian, Ohauan and Puaroan, numbers of individuals are generally low, and well preserved specimens are usually uncommon Faunal sequences are often interrupted by barren zones Large concentra- tions of specimens, to produce shellbeds, are very rare

l%e general paucity ofthe New Zealand ammonite record is in marked contrast to the richly abundant populations that lived in the tropical and sub-tropical shallow-water shelf seas of the Central Tethys Climatic and facies conditions in New Zealand were substantially different from those of the Central Tethys First, New Zealand was situated in mid- latitudes, probably between 40"s and 50% lat., and sea water temperatures were probably equivalent to those of the modem warm-temperate zone Because the Late Jurassic world was probably ice-free, global climates were generally equable, with a very wide tropicallsub-tropical zone, occupied by the richly developed Tethyan faunas In the Late Jurassic New Zealand was unequivocally marginal to this situation and, although Tethyan fauna1 elements were present, the cooler warm-temperate conditions then prevailing throughout New Zealand were undoubtedly less than optimal for their development Nonetheless, the absence at this time of anti-Boreal ("Austral") elements, that appeared later in the Cretaceous in response to cooling conditions, provides a clear indication that sea water temperatures did not fall to reach levels equivalent to those ofthe modem cool-temperate zone

Second, New Zealand straddled a tectonically active plate margin, and the Murihiku sediments, in which almost all of the ammonites are preserved, were laid down in an arc-trench situation, adjacent to amajor subduction zone developed along the southeastern edge of the Gondwana continent The fossiliferous components of the Murihiku sediments are therefore preserved in thick sequences of volcaniclastic sandstones, siltstones and tuffs that have undergone low-grade metamorphism, with any fossils present being overgrown and disrupted by the development of coarsely crystalline secondary minerals

Phylloceratidae are more richly represented in the Late Jurassic of New Zealand than might be deduced from the

1 Calliphylloceras empedoclis (Gemmellaro), Holcop~lloceraspolyo[c~rm (Benecke), Holcophylloceraspassari (Boehm)

mason; n subsp and Ppchophylloceras sp indet Tethyan affinities are particularly evident Lytoceratidae includes Lvroceras taharoaeme Stevens, which ranges up to a diameter of 1.5 m

erromphaloides Burckhardt: Aulacostephanidae by Epiceplralites marwicki n sp, and Subneumoyria cf ordonezi

(Burckhardt) Ataxioceratidae are well represented throughout the Late Jurassic sequence, except for in the lower

(Uhlig), K aff desmidoppcha (Uhlig) K pilicosta n sp., K mairietrsis n sp., K cf santarosana (Burckhardt),

Pnraholiceras flemingi n sp., R subspitiense n sp., P aff sabineanum (Oppel), P aff haugi Uhlig,

l

Pnrabnliceraloidesgrantmackiein sp., Pachysphinctes cf beyrichi (Futterer), Aulacosphinctoides brownei (Marshall),

A sisvphi (Hector), Kawkiasphinctes antipodus n sp., Srihplanites hirri~vaiettsis n sp., Subdichotomoceras

l

nraraetaiense n sp

(i) ldoceras zone, correlated with Early and Late Kimmeridgian

The Early Tithonian is either absent or poorly represented in the New Zealand sequence Based on an assessment of the validity ofthe tie-points that can be derived from the ammonite data, the New Zealand local stages have been assigned the following correlations: Heterian: Late Callovian-Early Kimmeridgian; Ohauan: Late Kimmeridgian-Middle Tithonian; Puaroan: Middle and Late Tithonian

The Late Jurassic ammonite assemblages ofNew Zealand show well-defined variations in the proportions ofLeiostraca and Trachyostraca and assessed values for faunal turnover, diversity and abundance Such variations are interpreted as being responses to environmental factors and reflect sedimentological and ecologicalfluctuations resulting from local tectonic activity and eustatic changes in sea level

In general, there is a good match between biotic and sedimentological changes and published eustatic models Mis- matches are probably related to contemporaneous local tectonic activity related to the early phases of the Rangitata Orogeny Occurrences of giant ammonites appear to coincide with the major phases of rising sea level Such occur- rences may be related to the generation of episodes of upwelling and general turnover ofthe water column that served

to lift on to inshore shelf areas representative samples of populations that were normally resident in deeper waters some distance offshore

Strong Tethyan provincial affinities are shown by the ammonite assemblages of the Late Jurassic ofNew Zealand The Leiostraca show circum-Gondwana links, but with some northwards extensions into Mexico, southern Europe, the Middle East and Asia Minor The Trachyostraca show a more restricted, hut nonetheless also circum-Gondwana set of affinities, but without any direct links to southern Europe, the Middle East and Asia Minor However, linkages to Mexico remain very strong The circum-Gondwana affinities of both Leiostraca and Trachyostraca reflect faunal migrations that occurred along shorelines extending around the margin of Gondwana Marked affmities exist with New Caledonia, Papua New Guinea, Indonesia, NW Himalaya, East Africa, Malaysia, southern South America and the Antarctic Peninsula While such circum-Gondwana links are compatible with conventional Gondwana reconstructions,

an even tighter fit can be achieved by the assumption ofan expanding earth thesis, making direct linkages between New Zealand and Central and South America even more of a physical possibility

Keywords Molluscs; Ammonoidea; Phylloceratidae; Lytoceratidae; Oppeliidae; Aulacostephanidae; Ataxioceratidae;

bour; Port Waikato; Marokopa; Awakino; Morrinsville; Humnui; Metric Map Sheets (l :50 OOONZMS 260) M34, N33, R13, R14, R15, R16, R17, T14

Late Jurassic strata in New Zealand

Ammonite occurrences in the Late Jurassic of New Zealand

Quantity, quality and state of preservation of ammonite material in the

Late Jurassic of New Zealand

Influence of climatic and tectonic environmental factors on the Late Jurassic successions of New Zealand

Kossmatia cf desmidoprycha Uhlig

Kossmatia aff desmidoptycha Uhlig

Kossmatia sp indet.? desmidoprycha Uhlig

Paraboliceras aff sabineanum (Oppel)

Paraboliceras aff haugi Uhlig

Nomenclature of perisphinctid taxa

Aulacosphinctoides brownei (Marshall)

Aulacosphinctoides sisyphi (Hector)

Relationship of ammonite zonation to bivalve zonation

Relationship of ammonite zonation to dinoflagellate zonation

Chapter 5 OVERSEAS CORRELATIONS

Introduction

Historical development

Subdivision of the Tithonian

Standard zones of the Kimmeridgian-Tithonian

Oraka Sandstone

Captain King's Shellbed, Ohinerurn Formation, Kiwi Sandstone

and Waikutakuta Siltstone

Kowhai Point Siltstone and Takatahi Formation

Lithological changes accompanying Late Jurassic eustaq

Relationship of ammonite biota to Late Jurassic eustasy

Giant ammonites and eustasy

Geological Survey fossil localities

University of Auckland fossil localities

University of Canterbury fossil localities

Canterbury Museum fossil localities

University of Otago fossil localities

Victoria University of Wellington fossil localities

The Natural History Museum (London) fossil localities

Abbreviations of collectors' names

PLATES

INDEX

LIST OF TEXT FIGURES

Fig I Some major contributors to the study ofNew Zealand Late Jurassic ammonites Fig 2 Map of the Murihiku and associated terranes in New Zealand

Fig 3 Map of the disposition of the Palaeozoic and Mesozoic terranes of New

Zealand before continental break-up

Fig 4 Cross-section through theNew Zealand Orogen in Early Cretaceous times

Fig 5 Platr tectonic reconstruction, 1.atc J u r z s ~ c

FIE 6 Keclonal dlstrihution of Junccic rockc Konh Island of N c a 7callnd

Generalised map of Jurassic lithological units, Kawhia Harbour

Detailed map of Jurassic lithological units exposed along the southern shore of Kawhia Harbour

Map of Jurassic lithological units, Port Waikato

Cross-section of an ammonite to illustrate the system of measurement

Phylloceras salima Kmmheck Whorl cross-section

Phylloceras salima Krumbeck Suture lines

Partschiceras otekense n.sp Whorl cross-section

Portschiceras sirigoceriforme n.sp Drawing showing spiral groove

Calliphylloceras empedoclis (Gemmellaro) Suture lines

Calliphyloceros empedoclis (Gemmellaro) Constrictions on internal mould

Calliphylloceras empedoclis (Gemmellaro) Whorl cross-sections

Holcophylloceraspolyo(cum (Benecke) Whorl cross-sections

Holcophylloceraspolyo/cum (Benecke) Suture line

Page

3

Ftg 20 / l o l c o p l ~ ~ l l o c e r o ~ p n l ~ ~ ~ l c r n ~ (Ilmc.ckc) (:oncrr~ct~ons on internal niould 2'1

F I E ? I llol~~or,hillnceru~ , noholr.um , Illcncckc~ Granh o t ' c o n s t r ~ c ~ ~ ~ n s ncr \rhorl 29

~ i g 22 Holcophylloceras passati ( ~ o e h m ) maioni n.'subsp Sketches of internal moulds 32

Fig 23.24 Lytoceras taharoaense Stevens Suture lines 35

Fig 25 Hector's original illustration of Uhligites hectori Spath 38

Fig 26 Boehm's original sutural diagram for Uhligites molutaranus (Boehm) 38

Fig 27 Aspidoceras cf euomphaloides Burckhardt Suture line 40

Fig 28 Epicephalites manvicki n.sp Whorl cross-section 43

Fig 30 Subneumayria cf ordonezi (Burckhardt) Whorl cross-section 44

Fig 38 Kossmatia cf santarosana (Burckhardt) Ribbing pattern 58

Fig 39 Parabolicerasjlemingi n.sp and P himalayanum Uhlig Suture lines 6 1 Fig 40 Aulacosphinctoides brownei (Marshall) Rib density curves and septation diagram 70 Fig 41.42 A~rlacosphinctoides brownei (Marshall) Suture lines 7 1 Fig 43 Aulacosphinctoides brownei (Marshall) Suture line illustrated by Boehm (191 l ) 71

Fig 44 Aulacosphinctoides sisyphi (Hector) Hector's original illustration 74

Fig 45 Aulacosphinctoides sisyphi (Hector) Rib density curves and septation diagram 75

Figs 46,47 Aulacosphinctoides sisyphi (Hector) Suture line 76

4 Fig 48 Aulacosphinctoides sisyphi (Hector) Suture line 77

Fig 49 Perisphinctes marshalli Spath Sutural diagram illustrated by Boehm (191 1) 77

Fig 50 Strbplanites huriwaiemis n.sp Ribbing pattern and whorl cross-section 82 Fie 51 Ammonites novo-zelandicus Hauer Hauer's orieinal illustrations U 87

Fig 52 Ammonites aucklandicus Hector Hector's original illustration

Fig 53 Stratigraphic ranges of ammonites in the Late Jurassic sequence ofNew Zealand Fig 54 Ammonite zones in the Late Jurassic of New Zealand

Fig 55 Relationship of Bivalvia zones to the standard Kawhia succession

Fig 56 Relationship of dinoflagellate zones to the standard Kawhia succession

Fig 57 Standard ammonite zones for the Tethyan Realm and their probable presence

in New Zealand

Fig 58 Faunal spectra for the Late Jurassic ammonite faunas of New Zealand, showing

fluctuations in percentage proportions of Leiostraca and Trachyostraca

Fig 59 Faunal spectra for Late Jurassic ammonite faunas of Northern ltaly

Fig 60 Relationship of lithology to eustatic fluctuations in the Late Jurassic of

New Zealand

Fig 61 Plots of first and last appearances, turnover, diversity and abundance for the

Late lurassic ammonite faunas of New Zealand

Fig 62 Occurrences of giant ammonites in the New Zealand Late Jurassic sequence

Figs 63 64 Gondwana reconstructions

Figs 65 66 Expanding earth reconstmctions

Figs 4, 5, 8 Partschiceras strigoceriforme n.sp

Figs 6, 7 Partschiceras aff partschi (Hauer)

Figs 1-4 CalliphyNoceras empedoclis (Gemmellaro) Figs 1-5 Calliphylloceras empedoclis (Gemmellaro) Figs 1 2 Holcophyllocerospolyolcam (Benecke) Figs 1-3 Holcophylloceraspol~volcum (Benecke) Figs 4, 5 Holcophylloceraspassafi (Boehm) masoni n, subsp

Figs 1, 2 Holcophylloceraspassati (Boehm) masoni n, subsp

Figs 1-7 Holcophylloceraspassati (Boehm) masoni n, subsp

Figs 1-4.6 Holcophylloceraspassali (Boehm) masoni n.subsp

Fig 5 Ptychophylloceras sp indet

Figs 1-3 Lytoceras faharoaense Stevens Fig 1 Uhligifes mofufaranrrr (Boehm) Figs 1-3 Uhligites motutaranus (Boehm) Figs 1-3 Uhligites motutaranus (Boehm) Figs 4, 5 Uhligifes keyesi n.sp

Figs 6-8 Aspidoceras cf euomphaloides Burckhardt

Figs 1 2 Aspidoceras cf euomphaloides Burckhardt

Figs 3-7 Epicephalifes marwicki n.sp

Fig l Epicephalifes marwicki n.sp

Figs 2, 3 Subneumayria cf ordonezi (Burckhardt)

Figs 4-9 Idoceros hereriense n.sp

Fig I ldoceros heteriense n.sp

Figs 2-4 Idoceras speighfi (Marshall) Figs 1-8 Kossmatia macnaugl~ti n.sp

Figs 1, 5 Kossmatia cf desmidoptycha Uhlig

Fig 2 Kossmatia aff desmidoptycha Uhlig

Figs 3.4 Kossmatio? cf desmidoptycha Uhlig

Fig 6 Kossmatiapilicosta n.sp

Figs 1-6 Kossmatia mairiensis n.sp

Figs 1-5 Kossmatia cf santarosana (Burckhardt)

Figs 6-9 Parnbolicerasjlemingi n.sp

Figs 1-4 Parabolicerasfimingi n.sp

Fig 5 Paraboliceras subspitiense n.sp

Figs 1, 2 Paraboliceras subspitiense n.sp

Figs 3 4 Paraboliceras atT sabineanum (Oppel)

Figs 5-7 Paraboliceras aE haugi (Uhlig) Fig 1 Paraboliceras aff haugi (Uhlig)

Figs 2-5 Paraboliceratoides granfmackiei n.sp

Fig 6 Pach.vsphinctes cf beyrichi (Futterer)

Fig 1 Pachysphinctes cf be.vrichi (Futterer) Figs 2-1 1 Aulacosphincroides brownei (Marshall)

Figs 1-8 Aulacosphincroides brownei (Marshall) Figs 1-2 Aulacosphinctoides sisyphi (Hector) Figs 1-4 Aulacosphinctoides sisyphi (Hector) Figs 1,2 Aulacosphinctoides sisyphi (Hector) Figs 1-3 Kawhiasphinctes antipodus n.sp

Figs 1, 2 Kawhiasphinctes antipodus n.sp

Figs 1 2 Kawhiasphinctes anfipodus n.sp

Figs 1-3 Kawhiasphinctes antipodus n.sp

Figs 4-6 Subplanites huriwaiensis n.sp

Figs 1-3 S~~bplanites huriwaiensis n.sp

Fig 4 "Perisphinctes" kmvhiae (Browne M S ) n.sp

Figs 5-7 Subdichotomoceras marefaense n.sp

Page

144

CHAPTER 1 LNTRODUCTION

HTSTORICAL BACKGROUND

Summaries of the history of Jurassic studies in New Zea-

land have been provided by Fleming and Kear (1 960) and

Waterhouse (1965)

The first Jurassic ammonites recorded from New Zealand

were discovered in 1859 by Ferdinand von Hochstetter

(Fig l) Hochstetter collected two ammonite specimens

6om near Kowhai Point, Kawhia Harbour (Hochstetter

p 10) These were later described by Hauer (Hauer 1863;

Hauer in Zittel, 1864, P1.8, Fig 1) as Ammonites Novo-

Zelandicus

James Hector had visited Kawhia in 1865-66 and provided

a report (Hector 1884, pp xxxiv-xxxv), but because ofthe

onset of hostilities and the subsequent closure ofthe King

Country to European visitors, no further ammonite collec-

tions were made until 1883, when the type ofA~nmonites

sisyphi was collected by W Rolleston (Hector 1884, p

xxxiv, 1886a,b; Marwick 1956) Substantial fossil collec-

tions, including ammonites, were also made in 1883-84

by Alexander McKay (McKay 1884) Thereafter, although

the few Jurassic fossils that were then known from New

Zealand were the subject of discussion and speculation in

the European literature (e.g Oppel 1865; Neumayr 1885:

Boehm, 1900, Haug 1910; Dacque l910b), no new mate-

rial was obtained until 1905, when R.A.S Browne (vide

MS notes) and H Suter (see Boehm 191 1, p 3) made col-

lections at Kawhia, including ammonites, which provided

the basis forpapers by Marshall (1909)and Boehm (191 I)

named after R.A.S Browne (Marwick in Browne 1952)

The next worker of note was the English geologist C.T

tensive collections in 1915 from the New Zealand Jurassic

and published an authoritative synthesis (Trechmann

4 2 3 ) , with an appendix on the ammo'ites contributed by

L.F Spath (Spath 1923) At about the same time, collec-

tions were also made from Kawhia by J.A Bamum (Uni-

versity of Auckland), and these were also made available

to Trechmann

While regional surveys that were carried out in the 1920s

and 1930s in the coastal Waikato (Henderson 191 8,1919;

Henderson and Grange 1922, 1926; Williamson, 1932;

Marwick 1946) had contributed greatly to the stratigraphic

framework of the New Zealand Jurassic, little additional

fossil material of importance was collected However, L.C

King and K.J McNaught (then at Victoria University of

Wellington) collected ammonites from Kawhia in 1931

and these, together with other New Zealand Geological

Survey material, were identified by Spath (1935a)

Marwick (1953) provided a summary of the systematic

status of many of the earlier collections

From the 1940s onwards substantial collections of valu- able material were collected by individuals, notably by

Browne, A.P Mason (Fig l), W Sutherland, B.E Thomson and J Gyles Collections were also made by student parties from the University of Auckland, led at various times by J.A Bartnun, E.J Searle, A.R Lillie and J.A Grant-Mackie These individual efforts provided the stimulus for a major re-study of the New Zealand Jurassic

1960), during which key collections ofammonite material were obtained During Fleming and Kear's study, repre- sentative collections of New Zealand Late Jurassic am- monites were sent to Dr W.J Arkell (Cambridge Univer- sity) for description (Fig 1) Unfortunately Dr Arkell died

in 1957, before the descriptive work had been completed However, before his death, he had provided preliminary determinations and comments on age relationships, and these were incorporated in Fleming and Kear (1960) and Fleming (1960) These preliminary determinations and comments, together with some manuscript notes made by

Dr Arkell, have been drawn upon in the present study Earlier, between 1943 and 1945, R.A.S Browne had made extensive notes on New Zealand Mesozoic ammonites, and the portions of these notes relating to Late Jurassic taxa have been an excellent source of locality information for some of the older collections

REPOSITORIES OF COLLECTIONS

The largest and most comprehensive collections of Late Jurassic ammonites are held by the Institute of Geological

&Nuclear Sciences (GNS), Lower Hutt, and the Depart-

The GNS collections, originally obtained by staff of the New Zealand Geological Survey, are the result of 130 years

of field collecting from all parts of New Zealand Each

lection number (prefix "GS") and all the specimens cited individually in the text of the present work have been as- signed specimen numbers from the Geological Survey Ceohaloood Reeister (orefix " C E ) Onlv brief locality A

details have been provided in the text; complete informa- tion is available from the GNS paleontological database and 6om the New Zealand Fossil Record File adminis- tered by the Geological Society of New Zealand The University of Auckland collection contains substan- tial holdings from Kawhia and Port Waikato Like the Geological Survey material, a collection number (prefix

" A V ) denotes a field collection and individual specimens are registered in the University of Auckland Department

of Geology Cephalopod Register (prefix "C")

Small collections of Late Jurassic ammonites are held by the Auckland Institute and Museum, Canterbury Museum,

Figure 1 (opposite) A selection of portraits of some of the major contributors towards the study ofNew Zealand Late Jurassic

ammonites

A - Ferdinand R von Hochstetter, geologist attached to the expedition around the world ofthe Austrian frigate "Novara" in 1857-

1860 Behveen December 1858 and October 1859 Hochstetter carried out a series of regional geological surveys in New

/c:+lnnJ I hc resullc ofthcrc survqs ~ v r r puhlishcd undcr the rirle.'(icolog~c s u n Ncu-Seelund' ( ~ o c l ~ ~ t c t t c r 1864) and illso

I I I tv.o oonulw accounts~llochstctlcr 1863 18671 (see also translnfion hv Flsm~ne , , - l9591 1)urlnea tune, ol'thc K~neCounm U

carried out in 1859, ~ochstetter discoveredthe first ammonites to be recorded from ~ew'zealand ~ m m ~ ~ i f e s ~ o v o - ~ e l a n d i ~ ~ ~

from near Kowhai Point Kawhia Harhour

Tle porvait is of a lithograph drawn by J Dauthage of Vienna of Hochstener in his 29th year of age, dated July 1859, and

originally published in Haast (1884) and republished in Rice et al (1959)

R - Patrick Marshall Photographed in 1950 by G.C Shaw Patrick Marshal1 (1869-1950) was a versatile geologist who held the

post ofprofessor of ~ e o & at Otago university from 1908 to 1916 (Waners 1996) His main claim to fame isas the originator

of the name ienimbrite and of the concent of the "Andesite Line" (called bv later authors the "Marshall Line") which is now ~~ ~ ~~ ~

recopnised as defining the western boundary of the Pacific Plate in the SW Pacific region He also had a major interest in

hlesozoic ammonites and in 1909 described ammonites that had been collected from Kawhia by R.A.S Browne in 1902 In

I41 5 ir4ar\hall i~ccornpantcd llic English gcoloelsl (: I l'rechmann on a lnalor tratcrsc of Knwhla Ilarhuur that resultud in thc

firrt derin~l~\r account5 of the 'rriusstc and I~lrass~c mala cxpc,.;cd around 11s shorcl~nc (Trechmann 1\11 8 1923)

C - Ken McNaught Photographed in 1972 Ken had graduated in geology and chemistry at Victoria University College (now

Victoria University of Wellington) in the early 1930s and along with Lester King, then a Lecturer, had participated in afield trip

to Kawhia Harbour during which a number of important ammonites were obtained Ken's subsequent scientific career was as a

soil chemist at Ruakura Aericultural Research Centre Hamilton However throuehout his career Ken maintained his interest U - in

geology and in the early 1950s, stimulated by the publication of Marwick's synthesis of Trias-Jura faunas (Marwick 1953) he

and his wife Ella made substantial and well-localised collections from the Kawhia region These collections were donated to the

New Zealand Geological Survey The availability of the McNaught collections in turn encouraged Charles Fleming and David

Kear to undertake their major study of the Kawhia Jurassic (Fleming and Kear 1960)

D -Charles A Fleming; E - David Kear, photographed just after the time of their Kawhia studies and when they held the positions

of respectively Palaeontologist and Geologist with theNew Zealand Geological Survey Joint authors ofthe definitive work on

the Jurassic of Kawhia Harbour (Fleming & Kear 1960) and collectors of numerous ammonite specimens The photographs

were taken in the late 1970s Photo D was taken by Robin Fleming, Charles Fleming's eldest daughter

F - Alan P Mason Photographed in 1993 While holding the appointment of Geologist at the Auckland Museum in the early 1950s,

Alan Mason collected ammonites from Kawhia and Port Waikato that were subsequently donated to the New Zealand Geologi-

cal Survey and Auckland University

G - W.J Arkell of the Sed-wick Museum, University of Cambridge who examined much of the material from the collections of

McNaught, Fleming & Kear The photograph was taken at Aylesbury in August 1948 by C.A Fleming during one of the field

excursions of the 18th International Geological Congress (London 1948)

University of Canterbury, Victoria University o f Welling-

ton and University of Otago

New Zealand material, chiefly that obtained by C.T

Trechmann, and described by Spath (1923) is held in the

Department of Palaeontology, Natural History Museum,

London

ACKNOWLEDGEMENTS

Many people have helped in the various stages ofthis study

and this much appreciated assistance is gratefully acknowl-

edged Access to field collections has been provided by

the University of Auckland (J.A Grant-Mackie and J.I

Sutherland) University of Otago (J.D Campbell and E

Fordyce), Victoria University of Wellington (S Eager) and

Canterbury Museum (M Bradshaw, K Watson) Photo-

graphic and cartographic assistance was provided by

Wendy St George (GNS) Editorial services were pro-

vided by J.G Gregory (Word Therapy) The manuscript

was typed and formatted for printing by Pat Bratton and

preliminary draughts by lrene Galuszka The manuscript

benefited considerably from reviews by G.J Wilson

(GNS), H.J Campbell (GNS), J.A Grant-Mackie (Uni- versity of Auckland), J Callomon (University College London), A Zeiss (University of Erlangen), and F Cecca (Istituto di Geologia, UniversitA degli Studi di Urbino, Italy) Dr M.K Howarth (Natural History Museum, Lon- don) kindly supplied photographs of New Zealand speci- mens included in the C.T Trechmann Collection (Trechmann 1923; Spath 1923)

The collections on which this study is based represent the combined efforts of geologists and palaeontologists ex- tending over a century or more For this reason it is per- haps invidious to single out any individual effort Never- theless, a special tribute should be paid to the work of Ken McNaught, who with his late wife Ella, systematically collected from the Kawhia sections in the 1950s and 1960s

These efforts, carried out entirely on weekends and holi- days, resulted in a wealth of accurately located material, all of which was donated to the New Zealand Geological Survey The McNaught collection formed a major key- stone for the present study and the continuing personal interest of Ken (and also that of Ella until her death) has been very much appreciated

CHAPTER 2 STRATIGRAPHY

INTRODUCTION

Earlier reviews of the New Zealand Jurassic include those

ofFleniing(1967.1970,1975); Stevens (1978a,c); Stevens

& Speden (1978); Lillie (1980), and these should be con-

sulted for details

Later reviews, placing the New Zealand Jurassic in a plate-

tectonic framework, include those of Bradshaw et al

& Ballance (1989), and Bradshaw (1989, 1994)

LATE JURASSlC STRATA IN NEW ZEALAND

Late Jurassic sedimentaryrocks inNew Zealand areknown

to occur in five separate successions, each with a distinc-

tive tectonic history, range of facies and fossil biota, and

separated from each other by majortectonic structures (Fig

2) In terms of plate tectonic syntheses, these units are

currently recognised as terranes

The pre-Late Cretaceous terranes of New Zealand are

grouped into two provinces of contrasting geology, West-

em and Eastern, separated by the Median Tectonic Zone

Jurassic strata are today sited in the Eastern Province, i.e

on the Pacitic Ocean side of the terranes of the Western

Province, composed of Paleozoic rocks, which originally

formed part ofthe Pacific edge ofGondwanapriorto Early

Cretaceous time (when rifting began on the site of the

Late Jurassic rocks occur in the following terranes:

(i) Murihiku, Drumduan and Waipapa terranes (includ-

ing the Hunua and Morrinsville facies), of Permian to

Jurassic age These terranes are formed largely of

volcanics or volcanic-derived sediments and are inter-

preted as representing an arc-trench system developed

along the oceanward side of the Gondwana margin,

and separated from it by a marginal sea (MacKinnon

1983; Muir et al 1995) The original structural sys-

tem was probably very complex and undoubtedly in-

cluded arcs that have now been removed by tectonic

dian Tectonic Zone represents a zone of deformation

and separation between these arc-hench (volcanogenic)

terranes and the terranes of the Western Province

(Bradshaw 1989, 1993; Kimbrough et al 1994;

within the Torlesse Terrane: Rakaia, Pahau and Esk

Head

extensive of the tectonic terranes that are present on terrestrial New Zealand It is interpreted as represent- ing an accretionary prism developed along a hench- transform system Contact with the Caples Terrane to the west has been subsequently obscured by develop- ment of the Haast Schist zone but it is recognisable geochemically (Mortimer 1995a,b) The Older Torlesse is the only terrane that is thought to have origi- nated outside the New Zealand region (Adams 1996) (b) Younger Torlesse (or Pahau Subterrane), of Late Jurassic to Early Cretaceous age Rocks mapped as Younger Torlesse generally resemble those ofthe Older Torlesse rocks, but differ 6om them in containing a much larger percentage of sediments derived from an older sedimentary and metasedimentary source, most probably Older Torlesse and Haast Schist (Bradshaw

et al 1981; MacKinnon 1983; Bishop et al 1985; Coombs 1985; Mortimer 1995a,h) The Younger Torlesse rocks represent an accretionary prism thought

to have been developed against the oceanward side of the uplifted and partially metamorphosed Older Torlesse, from which they are separated by the Esk Head Subterrane (Silberling et al 1988)

(c) Esk Head Subterrane of Late Triassic to Late Jurassic age The Esk Head Subterrane is a continu-

ous belt oftectonicmClange, generally 10-20 lan wide,

South Island Although various plate-tectonic models have been proposed to explain the origin of the Esk Head Mtlange (cf Silberling et al 1988), it is likely that it is the product of tectonism associated with the renewal of subduction that led to the accumulation of the Pahau Subterrane, on the Pacific side ofthe Rakaia Subterrane, after the latter had been sutured on to the Caples Terrane (Howell 1980)

The New Zealand Late Jurassic sedimentary sequences were deposited during the time when the volcanogenic terranes were being actively sutured on to the terranes of the Western Province along the Median Tectonic Zone

At the same time, the Older Torlesse Subterrane was be- ing either rafted in from the Pacific or accreted along the Pacific edge of proto-New Zealand (depending on the tec- tonic model adopted) (Figs 3-5) These tectonic phases together constitute the Rangitata Orogeny, that began about 190 Ma and ended about 120-110 Ma The tectonism associated with the accretion and suturing of the volcanogenic and Torlesse terranes gave way to the onset of a phase ofriftiig that preceded the opening ofthe

(a) Older Torlesse (or Rakaia Subterrane) of Permian

to Jurassic age This subterrane is areally the most

a) Rakaia (= Older Torlesse)

b) Pahau (=Younger Torlesse) 7b

Figure 2 Map ofNew Zealand showing the present day distribution ofterranes containing Upper Carboniferous to Lower Cretaceous strata which were amalgamated during or before the Rangitata Orogeny Based on Bishop et d (1985), Norris & Craw (1987), and Spbrli (1987)

The distribution of exposed lurassic outcrops in the Murihiku Supergroup is shown by the darkest pattern, and the approximate distribution of concealed Murihiku rocks in the North Island is shown by the next darkest pattern Many areas of covering younger rocks have been disregarded Except for a small occurrence of Puaroan strata at Pyke River, N.W Otago (McKellar et

al 1962), Late Jurassic marine rocks are found only in the North Island, in the area between Awakino and Port Waikato However, such a discontinuous distribution pattern is probably largely a reflection of present erosional levels rather than indicating original deposition patterns within the Murihiku sedimentary basin

Jurassic & Cretaceous accretion

' ' Pen

Figure 3 Opinions v a v as to the original disposition ofthe terranes depicted in Fig 2 This simplified palaeogeographic map based on Bradshaw (1989, fig 1) shows his version of the disposition of the Paleozoic and Mesozoic terranes of New Zealand before the continental break-up phase of the midCretaceous and the dextral shear events oftheNeogene The Murihiku Terrane accumulated as arc deposits immediately offshore from the Gondwana continental margin The Torlesse Terrane consists of a collage of separate sedimentary prisms that have been railed in over various distances

at various times during Permian-Early Cretaceous and then welded on totheNew Zealand Orogene

A broader view of the plate tectonic situation is depicted in Fig 4 M.T.Z =Median Tectonic Zone

TORLESSE SEDIMENTARY PRISM

vuhua) B.S Mu : M D , C ; Subterrane Melange Subterrane

Figure 4 Generalised cross-section through theNew Zealand Orogene in Early Cretaceous times according to the interpretation of

Fcrriere and Chanier (1993 Fig 8) The cross-section traverses the southern part of the South Island The Pahau Subterrane

the youngest component ofthe Torlesse sedimentary prism, completed its docking phase in the Late Jurassic and Lower Cretaceous

BS = Brook Street volcanic arc: Mu = Murihiku: M = Maitai: D = Dun Mountain Ophiolite; C = Caples volcaniclastic suite

Figure 5 Various interpretations exist as to the plate tectonic situation in the Late Jurassic This interpretation, based on that of Wilson et al (1989) shows their version of the wider tectonic regime that was influencing the events in New Zealand, depicted

suturing of the individual accreted components of the Torlesse Terrane By Early Cretaceous times the lzanagi Plate had largely been consumed in the New Zealand region and the subduction regime ofthe Triassic and Jurassic was replaced by one ofactive

JURASSIC O F NEW ZEALAND

Murihiku Terrane

With the exception of three localities in the Younger

Torlesse (see below) all occurrences of Late Jurassic am-

monites are in Murihiku (or Hokonui) strata (Murihiku

Terrane of Howell 1980) (Fig 6) The Murihiku strata

have been variously interpreted as having been deposited

in a fore-arc basin (Coombs et al 1976; Carter et al 1978;

Bradshaw 1989, 1994), an inha-arc basin (Howell 1980),

or a back-arciintra-arc basin (Coombs et al 1992) aligned

Campbell 1993; Muiret al 1995; Mortimer 1995a.b) The

predominant Murihiku sediments a r e feldspathic

sandstones and siltstones Numerous interbedded con-

glomerates also occur Carbonates are virtually absent

Collectively, the Murihiku sediments can be viewed as

being largely of epiclastic volcanogenic origin Innumer-

able thin interbeds ofvitric and crystal-vitric tuffs are also

ited from distal volcanic airfalls into the ocean, although

some may have been redeposited from the land

Taken together, the Murihiku rocks are characterised by

the following features: (i) composition (feldspathic

sandstones and siltstones); (ii) a great thickness of essen- tially conformable strata; (iii) internal structure character- ised by folds of great amplitude, wavelength and lateral continuity; (iv) a great lateral extent of individual sedi- mentary units; (v) a widely dispersed fossil component, allowing good regional correlation

Apart from being offset by 480 km on the Alpine Fault in the South Island, the Murihiku strata are continuous from the southeastern coast ofthe South Island, and thence along the western side of the country, to the north of the North Island The Cenozoic deformation of New Zealand has bent the Murihiku rocks overall into a lazy Z-shape They are concealed in places by younger rocks

Very similar rocks and fossils are found in New Caledo-

1985), and there is likely to be some form of lateral conti- nuity between New Zealand and New Caledonia along the

Wellman 1988; Mortimer 1995b, fig I)

No stratigraphic lower contact of Murihiku rocks is known, but there are places where the boundary against the neigh- bouring Dun Mountain-Maitai Terrane, of largely Petmian age, appears to be a line of only minor discontinuity

The whole Murihiku column has undergone low-grade

Supergroupi

LITHOLOGIES (SECTION ONLY1

Orangiwhao Andesite (Upper Cenozoicl

Siltstone and sandstone

Prominent sandstone

Prominent canglomerate

KAWHIA REGIONAL SYNCLiNE

support to the idea that they were originally a thick pile of

of the various Permian-Mesozoic terrane blocks of New stacked sediments, more than 15 km in thickness The

Zealand

zeolite mineralogy in the youngest known Murihiku rocks

Figure 6 (opposife) Between Awakino and Port Waikato, on the western coast ofthe North Island, westwards from Hamilton, Te Awamutu and Te Kuiti the Jurassic rocks of the Murihiku Supergroup have been folded into a large spclinorium, the Kawhia Regional Syncline

Although inland outcrops are often restricted by the great depth of weathering and by vegetative cover, good exposures are usually to be found in major rivers and streams However, the best outcrops occur in coastal exposures and particularly around the shorelines of the large embayment of Kawhia Harbour

Seismic profiles and petroleum exploration wells have indicated that the Triassic/Jurassic rocks continue offshore towards

and Campbell 1993) Towards the east a faulted contact exists along the Waipa Fault To the northwest the Murihiku rocks extend offshore to underlie part ofthe Norfolk Ridge and thence continue to New Caledonia (Paris 1981) To the southwest the Murihiku rocks continue under Cenozoic cover in Taranaki (Hornibrook 1953) and extend to intersect the Alpine Fault in the Nelson area The main feature of the map shows the geographic distribution of the lurassic component (Oteke, Kawhia and Herangi Series) ofthe Murihiku Supergroup The areas of outcrop that are shown on the map largely ignore a patchy covering

1978)

the North island the eastern contact is faulted (Kear, 1960);

the western contact is not seen on land, but offshore seis-

mic profiles suggest that it is thrust westward over Cenozoic

1993) Howell (1980) noted that both eastern and west-

em margins of the Terrane have been subject to tectonic

erosion, and as a consequence the basinal form of Murihiku

rocks can only be deduced by reconstruction from the sedi-

ment fill

The extensions of the Murihiku Terrane, in northerly and

southerly directions beyond the present New Zealand land-

mass are based on inference In the southeast ofNew Zea-

land the Murihiku Terrane passes offshore, to underlie part

of the Camphell Plateau (Bradshaw et al l996), and in

the northwest to underlie part of the Norfolk Ridge and

thence to continue northwestwards to New Caledonia

(Black 1996) There is little information from either re-

gion other than that derived from marine seismic interpre-

tation

The Late Jurassic ammonite localities of the Murihiku

Supergroup occur in sequences exposed along the west-

e m side of the North Island of New Zealand, and spread

along the entire exposed length of the Kawhia Regional

Syncline (Fig 6) (Kear 1978) Most of the localities oc-

cur around the shorelines of the large embayments and

estuaries that indent the western coastline (e.g Kawhia

Harbour, Aotea Harbour, Port Waikato) These indenta-

tions provide very well exposed and often reasonably con-

tinuous outcrops through the sequences ofthe western flank

of the Kawhia Regional Syncline Scattered ammonite

localities also occur inland, in rocks oftbe eastern flank of

the Regional Syncline

The greatest concentration of ammonite localities occurs

on the northern and southern shores of Kawhia Harbour

also occur in the Port Waikato area, 50 km to the north of

Mackie 1978; Waterhouse 1978) (Fig 9) The Port

Waikato area is also of significance because here the

Jurassic marine sequence extends up to a level that is suh-

stantially higher than that exposed at Kawhia (Fig 9) The

area between Port Waikato and Kawhia has only yielded

scattered ammonite localities: Te Akau (Kear 1966, 1987);

Raglan (Waterhouse& Kear 1991); AoteaHarbow (Player 1958) (Fig 6)

The sequence described by Player (1958) from the Aotea Harbour area is noteworthy because exposures continue

to a level stratigraphically higher than those of the upper- most Puti Siltstone at Kawhia (Stevens 1965, fig 12) However, the highest beds of the marine Jurassic, present

at the top of the Port Waikato sequence, are not exposed

in this area

Inland from Kawhia Harbour ammonite localities are sparse (e.g Clarke 1959), although some good collections have been obtained from the Awaroa Valley (Henderson

& Grange 1926) South of Kawhia, richly fossiliferous ammonite occurrences are known from the Whakapirau-

Grant-Mackie 1995), includingthat ofNewZealand's larg-

South of Taharoa, very few ammonite localities areknown: from Marokopa (MacFarlan 1975) and Awakino (Grant- Mackie 1959) In the Awakino area, Palmer Creek ex-

1923, p 23; Francis 1977) that is equivalent to the Ohineruru Formation and the Captain King's Shellbed of

Torlesse Terrane The only ammonite occurrences in the Torlesse are in the foothills area of northern Canterbury The holotype of

Idoceras speighti was found as a concretion in the bed of

the Hurunui River, near Ethelton (Marshall 1924)

Phylloceras cf salima Krumbeck has been found in situ

in the Ethelton Conglomerate, near Ethelton (GS 6166,

1978b, p 259) Although the holotype o f l speighti was found as a loose concretion, it is likely that it had been derived from the Ethelton Conglomerate, as Late Jurassic fossils are known from this formation and in the adjacent KaiwaraValley (Stevens 1965, pp 95-104; Wilson 1982;

Previous work has shown that clasts within the Ethelton Conglomerate range in age from Heterian to Puaroan (Maxwell 1964; 1975) and it is likely that these provide

Figure 7 Kawhia Harbour is the type locality for the Jurassic succession of Neir Zealand The harbour was originally an extensive river system that was eroded across the regional strike of the Jurassic rocks During the post-glacial Flandrian Transgression the river system was extensively flooded by the rising sea level, to form the present day harbour embayment Subsequently, the majority of the shoreline outcrops have been cliffed by marine erosion, to produce substantial and often laterally continuous exposures The map is asimplified version based on Flemingand Kear(1960) and shows the distribution of Jurassic lithological units Marine fossils of Late Jurassic age occur in strata ranging upwards from the lower levels ofthe Kirikiri Group The areas on land that have no patterns are post-Jurassic deposits (chiefly Quaternary dune sands and flat-lying Cenozoic sedimentary rocks) Some small areas of post-Jurassic cover deposits have been omitted (see Waterhouse and White 1994 for details)

the source for the ammonite specimens However, as clasts concept that the Older Torlesse had originated some dis-

of Early Cretaceous age have also been recorded by Wilson tance from New Zealand and had been rafted into place

& Helby (1988) it is evident that the fossil record repre- Some time in the Early Jurassic (Howell 1980; Coombs & sented by the ~ ~conglomerate h ~also extends into l ~ post- ~ COX 19911, it is significant that ammonites that elsewhere ~

Pahau Subterrane, but not in the Rakaia Subterrane The Ethelton Conglomerate and the associated sequences

in the Kaiwara Valley have been mapped as Pahau Sub-

terrane (Younger Torlesse) (Silberling et al 1988, fig 1)

It has been proposed (e.g Sporli 1987; Sporli & Ballance

1989; Silberling et al 1988) that the Pahau Subterrane is

an accretionary sedimentary prism that accumulated in Late

Jurassic and Early Cretaceous times along the oceanward

edge ofthe Older Torlesse (Rakaia Subterrane) and is sepa-

Furthermore, the two ammonite taxa that are recorded from the Pahau rocks have wide-ranging geographic affinities and, in the instance of Phylloceras, it is of a group (Leiostraca) that is widely viewed a s bathypelagic (Kennedy & Cobban 1976; Westermann 1990; Cecca et

al 1990; Cecca 1992) Therefore, the non-Murihiku am- monite occurrences lend support to the concept that, while the Youneer Torlesse was deposited some distance off- rated from it by an extensive zone of tectonic melange shore, asindicated by the interpretation that it was only (Esk Head Subterrane) Accumulation of the Pahau sedi- accessible to populations of wide-ranging (presumably mentary prism is considered to have occurred after the bathypelagic) taxa, nonetheless it was sufficiently close to Rakaia sub-terrane had been docked against the margin of the site of the Murihiku sedimentary complex to be able to theNew Zealand segnent ofGondwana (Sporli & Ballance share at least some components of the shelf fauna, albeit

1989, p 179) Thus, in view ofthe wide acceptance of the the more mobile ones

Figure 8 Detailed map of Jurassic strata exposed along the southern shore of Kawhia Harbour Based on Flerning & Kear (1960) and Kear (1978) In the area covered by this map, the highest unit, the Puti Siltstone, is not very well exposed because of poor outcrops around the tidal estuary of the Waiharakeke Inlet and the presence of extensive bush-clad and deeply weathered areas immediately inland The best outcrops of Puti Siltstone are to be seen in the cliffed edges and shore platforms at Puti and

These mklange blocks are interpreted as being tectonic

The present New Zealand Jurassic bioshatigraphic classi- slivers that were scraped off hom the surface of an exten-

More recent summaries are in Stevens (1978a,c) Stevens

Nomenclature

The Late Jurassic of New Zealand has been subdivided

The Heterian Stage, introduced by Marwick (195 1,1953)

has its type section on the south side of Kawhia Harbour

ing the incoming of Retroceromus gala; At the type lo- the second on the appearance of Malayomaorica

ma~qomoorica ( ~ ~ bappears some ~ ~ k ) above Retroceramus cf subhaasti These zones were termed

(1975) recognised three zones within the Heterian: the f ~ s t were proposed by Arkell in Fleming and Kear (1960) and

Figure 9 (opposite) Although Jurassic rocks occur intermittently in the region between Kawhia Harbour and the mouth of the

Along the southern side of the mouth of the Waikato River an extensive headland region has exposed a series of outcrops extending across the strike of the Jurassic rocks Although the succession tends to mirror that of Kawhia (Figs 7,8) there are some regional variations in lithology However, the most notable difference is that the marine succession extends higher than that at Kawhia- exposing higher levels in the Puti Siltstone that are not present at Puti and Motutara Bluffs and introducingtwo higher marine formations, the Coleman Conglomerate and Waikorea Siltstone The laner formation is overlain by the Huriwai Group, consisting of a basal marine unit, the highest marine beds of the New Zealand Jurassic followed by a complex of non-

I he m m h;ts hctn slnl~lificd fiom I'urser (1961) wd W.tlcrhousc t 197X)

The areas of land that h e without pattern comprise post-Jurassic rocks (chiefly Quaternm sands north of the Waikato and late Cenozoic sedimentaries south of the Waikato) Immediately northwest of Port Waikato, the Jurassic strata are downfaulted along the Port Waikato Fault (Hochstein andNunns 1976) and their continuations are concealed by either the seaar Quaternary and Late Cenozoic units

King's Shellbed, with a rich and diverse molluscan and

brachiopod fauna, is at the base of the middle Heterian

The shellbed can be traced at intervals along its outcrop

kom Kawhia to the Awakino Valley (Francis 1977)

Ammonites, belemnites, buchiid and inoceramid bivalves

are relatively common in the Heterian and most also have

affinities that extend well beyond the New Zealand-New

Caledonian region There is, therefore, much information

on which to base detailed international correlations How-

ever, some of the data are contradictory, and both the cor-

relations and the dating are subject to some debate (Stevens

1978a,c, 1990; Helby et al 1988)

Until recently, it was thought that the Oxfordian in New

Zealand was missing or represented entirely by non-ma-

rine strata (e.g Fleming 1970) However, Hudson et al

(1987) have shown that the Oxfordian ammonite

Epimayites is present in the lower part of the Oraka For-

mation at Totara Peninsula, Kawhia, together with Late

Callovian dinoflagellates and the lowest Retroceramus

galoi in the type section Correlation ofthe Heterian with

the Late Callovian, Oxfordian and Early Kimmeridgian

stages is adopted here

Ohauan Stage

The Ohauan Stage was introduced by Manvick (1951,

1953), with a type section near Ohaua and Lemon Points,

on the south side of Kawhia Harbour (Fig 8) The type

section was described in detail by Fleming and Kear

(1960), who defined the base of the stage as being the

incoming of Retroceramus haasti On the basis of the first

Puaroan Stage The Puaroan Stage was introduced by Manvick (1951, 1953), with a type section to the southeast of Kawhia Har- bour (Fig 8) The type section was described by Fleming and Kear (1960) and the definition of the stage was re- vised by Challinor (1977) Challinor defmed the base of

the stage on the first appearance of Ifibolithes arkeNi

grantmackiei Challinor and proposed two substages:

an older Mangaoran and younger Waikatoan He defined the base of the Waikatoan on the first appearance of

Belemnopsis aucklandica aucklandica (Hochstener) The

Waikatoan includes the youngest marine rocks of the Kawhia Syncline, and the overlying non-marine Huriwai Formation At Kawhia Harbour the Mangaoran includes the uppermost 10 m of the Kinohaku Siltstone, the full thickness of the Waiharakeke Conglomerate and three- quarters of the Puti Siltstone (Challinor 1977; Meesook

correlated with the Late Tithonian by Stevens and Speden (1978), and Helby et al (1988), while Stevens (1990) sug- gested correlation of the lower Puaroan with the Early Tithonian The present studies indicate that the bulk of the Puaroan (i.e Mangaoran and the lower Waikatoan) should be correlated with the Middle Tithonian The up- permost Puaroan (i.e upper Waikatoan) is considered to

be of Late Tithonian age, although the non-marine strata could be as young as Early Cretaceous

QUANTITY, QUALITY AND STATE O F PRESERVATION O F AMMONITE MATERIAL IN

T H E LATE JURASSIC O F NEW ZEALAND

-

appearance of R haasti, Meesook (1 989) placed the base

ofthe Ohauan stage atthe base ofthe Waikiekie Tuffaceous

(i) those strata deposited between the incoming ofR haasti

and the last appearance o f M malayomaorica; (ii) between

the last M malayomaorica and the first appearance of

Belemnopsis aucklandica trechmanni; (iii) between the

incomings of Belemnopsis a trechmanni and Hibolithes

arkelli grantmackiei Stevens (1990) correlated the

Ohauan with the Late Kimmeridgian and Early Tithonian;

The Late Jurassic strata of the Mumhiku Terrane of New Zealand generally consist of sequences dominated by volcaniclastic siltstone, sandy siltstone and sandstone, but

in the siltstones and fine-grained sandy siltstones, often in concretions Specimens are generally rare in sandstones and conglomerates, and, when present in these lithologies, their shell material has 6equently been leached away so that only moulds remain

13

grade metamorphism, and as a result many specimens are

sites for the growth of zeolite crystals (see Stevens 1985)

Such crystal growth may be very extensive and in extreme

instances may obscure and disrupt the structural details of

the ammonite conch

In other non-concretionary siltstones of the Heterian, am-

monites are usually preserved as completely flattened lat-

eral impressions, and all shell material has been leached

away However, in these instances latex casts can be made

to provide "positives" of the impressions

Although ammonites are present throughout the Ohauan,

they tend to be concentrated in the finer siltstone sequences

Thus the Kowhai Point Siltstone (Fig S), for example,

which has a sandy component developed particularly in

its upper half, has few ammonites By contrast, the

Kinohaku Siltstone (Fig X), with fewer sandy intervals,

has generally a broad representation o f ammonites A

concretionary bed, the Mairi Ammonite Bed, about half

way through the Kinohaku Siltstone, has yielded numer-

ous well-preserved ammonites The matrix of the concre-

tions is a highly indurated grey siltstone Although some-

times specimens are disrupted by septarian cracks, preser-

vation is generally good, and there is an absence of the

zeolitisation that is often present in concretions derived

from the Heterian

In the Puaroan, ammonites are rare or absent in the

ammonites have heen collected from concretionary hori-

zons in the siltstone sequences The concretionary beds at

Puti and Motutara Points are particularly significant, and

numerous large concretions are present, both in the cliffs

nature, and in these septarian concretions ammonite speci-

mens are often disrupted by extensively developed vein

systems The uppermost levels of the Puaroan, exposed

in the Port Waikato area, have extensively developed sandy

or conglomeratic intervals and are of near-shore environ-

ments that were generallv unfavourable to marine life

observations about the features of the aperture and the pres- ence ur absence of lappets Interestingly, the holotype of

(diameter 1.5 m), is one of the very few New Zealand ammonites with a largely intact body chamber and aperhual collar (Stevens 1985)

specimens -have placed major constraints on the determi- nation of the morphological and ontogenetic variability of the taxa that are present Also, because of the restricted sample sizes, some ofthe taxa in this study have been based

on a less than desirable number of specimens However,

it was considered that rather than leave such taxa in open nomenclature, their stratigraphic usefulness warranted spe- cific description

The general poverty o f the New Zealand ammonite col- lections has also hampered study of possible dimorphic variation As a consequence, in most instances aconserva- tive approach to taxonomy has been adopted, with stratigraphic utility being of prime consideration A simi- lar approach has been taken by Oloriz and Rodriguez-Tovar (1993), for example, in comparable circumstances

INFLUENCE OF CLIMATIC AND TECTONIC ENVIRONMENTAL FACTORS ON THE LATE JURASSIC SUCCESSIONS OF NEW ZEALAND

The classical ammonite successions ofEurope, which form the basis for much ofthe systematic and biostratigraphical framework of the group (e.g Arkell 1956), constitute the fossil record of the richly abundant populations that lived

in the tropical and sub-tropical shelf seas of the Central Tethys, often in association with coral reefs (e.g Barthel 1978; Ziegler 1965,1987; Barthel et al 1990; Fliigel1994;

water conditions favoured the growth of large and diverse assemblages, and frequently gave rise to richly fossiliferous shell hanks ("lagerstatten")

The few ammonites that have been recorded from the

Upper Puaroan at Port Waikato, while originally preserved

in concretions, have in most instances been exposed to the

effects of sub-aerial weathering As the Upper Puaroan is

only exposed in inland localities, this weathering is rather

pervasive Thus much of the available material has been

corroded, or is preserved only as impressions However,

latex positives have heen prepared from the latter

the world in the Late Jurassic was ice-free (Hallam 1975, 1985) global climates were generally equable, with a very wide tropicallsub-tropical zone occupied by the richly developed Tethyan faunas In the Late Jurassic, New Zea- land was unequivocally marginal to this situation (Fig 63) and, although Tethyan fauna1 elements were present, the cooler warm-temperate conditions then prevailing through- out New Zealand were undoubtedly less than optimal for their development Nonetheless, the absence at this time

Second, New Zealand was sited in a tectonically active of these climatic and tectonic factors, the New Zealand

'One developed along the edge of the nas occur spasmodically, theirnumbers are generally small, Gondwana continent (Wilson et al 1989; Dalziel 1992)

(Figs 3-5) The fossiliferous components ofthe Murihiku

CHAPTER 3 SYSTEMATICS

TERMINOLOGY AND CRITERIA FOR

CLASSIFICATION

The terminology and criteria for classification follow those

of Arkell (1935-1948), Arkell et al (1957), and Cox

(1988) Arkell cited four criteria as being the most useful:

(i) shell dimensions, (ii) whorl shape and coiling, (iii) septal

sutures, (iv) ribbing (for discussion see Cox 1988, pp 10-

14) Of these criteria, the style of ribbing has provided a

particularly valuable basis for classification of the New

Zealand material, particularly in the identification of ma-

terial which often has none or only imperfect sutures

The morphological terms are those used by Arkell et al

(1957), supplemented in the case of the perisphinctids by

Zeiss (1968)

SUPRAGENERIC CLASSIFICATION

The suprageneric classification that has been adopted is

based primarily on that proposed by Arkell et al (1957)

and Donovan et al (1980)

has been the subject of some contention Arkellet al (1957)

placed both in Subfamily Ataxioceratinae Buckman 1921

Bemasellidae Spath 1922, Subfamily Berriasellinae Spath

to Family Ataxioceratidae Buckman 1921, its subfamilial

placing remained ill-defined: it being included in either

Subfamily Ataxioceratinae Buckman 1921 or Subfamily

Lithacoceratinae Zeiss 1968

Paraboliceras was classified by Donovan at al (1980) as

Family Neocomitidae Salfeld 1921, Subfamily

Berriasellinae Spath 1922

MEASUREMENT OF SPECIMENS

The dimensions of the specimens that are listed in the ta-

bles that accompany the descriptions oftaxa have all been

measured on the internal mould (or estimated if test is

present) The following abbreviations have been used for

the dimensions and the derivative formulae (after Morton

1975) (Fig 10)

illustrate the measurements that are made, if preservation

Wh

measured from umbilical seam to umbilical seam

Many of the New Zealand specimens, particularly those

e o m the Heterian and Ohauan, are not suitable for meas- urement This is because the specimens are: (i) distorted; (ii) incomplete; (iii) obscured by firmly adhering matrix; (iv) flattened impressions; (v) preserved as one-sided views

of the conch (as is the situation in many concretions) Therefore, the tables of dimensions and formulae that ac- company the descriptions of taxa constitute only a small sample of the available material However, the tables serve

to provide a limited data set relating to the overall mor- phology exhibited by the taxa described

SUTURAL DIAGRAMS

have been annotated following the sutural terminology of

n

developed between the lateral lobe

and the umbilicus, the formation of which pushes the lateral lobe 6om its umbilical position out on to the flanks of the conch

Internal lobe Internal lobe with a septal lobe (a bifid extension of the internal lobe that climbs up the face of the pre- ceding septum)

tribution In view of the strong possibility that at least some of the New Zealand ammonite taxa display develop- mental polymorphism, rather than the dimorphism that is linked by some authors with sexual differentiation, a con- servative approach has been adopted with respect to tax-

Melendez 1993)

SYSTEMATIC DESCRIPTIONS

1971); Callomon (1963, 1969, 1981), and Westermann

(1964b, 1969b), an extensive literature has developed on

the topic of dimorphism in ammonites; particularly bear-

ing on its significance and systematic treatment

A number ofauthors have accepted that the dimorphism is

sexual in origin and, in recognition of this position, have

used the standard biological sex symbols in their taxonomy

writer's opinion this assumption is not entirely valid as

there still remain problems that hinder general acceptance

of sexual differentiation in ammonites (e.g the stratigraphic

separation of putative sexes and the lack in some collec-

tions of even an approximation to numerical balance (i.e

In view of these reservations a number of authors have

adopted a restrained approach and have retained conven-

tional taxonomy, but with recognition of size classes, or

morphs (Elmi 1969; Tavera 1985; Sarti 1993, and Ahops

& Melendez 1993) As an alternative to the hypothesis of

sexual dimorphism, Matyja ( l 986, 1994) has put fonvard

the concept of developmental polymorphism This hy-

pothesis postulates that the occurrence of various num-

bers of ammonite morphs with identical initial stages of

ontogeny, but differing in final shell size and morphology,

is due to a variation in the time needed for sexual matura-

tion of individuals (Bucher et al 1996; Davis et al 1996)

The basic difference between both hypotheses is that ac-

cording to the theory of sexual dimorphism forms differ-

ing in size represent different sexes, while according to

the hypothesis of developmental polymorphism they rep-

resent forms differing in the time of reaching sexual matu-

rity For example, the earlier maturation ofthe microconch

means that it has a shorter life and as a consequence at-

tains a smaller shell size and earlier stages ofmorphologi-

cal development

When viewed in the context of the New Zealand ammo-

nite fauna the approach of Matyja (1986, 1994) appears

to have much to recommend it In Lytoceras faharoaense,

for example, three distinct size classes can be distinguished

(small, medium, large) (Stevens 1985a), similar to those

recognised in modern squid populations and in the

Oxfordian ammonites studied by Matyja (1986, p 57;

1994) Similarly, the Aulacosphinctoides of the Puti-

Motutara region display a comparable tripartite size dis-

The present study indicates that Phylloceratidae are more richly represented in the Late Jwassic of New Zealand

stead of the single genus Holcophylloceras known in 1953,

when Manvick reviewed the fauna, (1953, pp 114,115), there are now five genera recognised (or genera and

subgenera), with at least one species each, viz.: Phylloceras (S S.), Partschiceras, Calliphylloceras, Holcophylloceras and Ptychophylloceras

GENERIC DIAGNOSIS (Arkell et al 1957, p 187): Invo- lute, compressed forms with gentle umbilical slope, dense fme radial lirae on test but not on internal mould, and some more or less vague radial folds on whorl sides Sutures with hiphyllic saddles In his revision ofthe phylloceratid ammonites Wiedmann (1962, 1964) adopted a position comparable to that of Arkell et al (1957) However, a different position has been taken by JoIy (1970a, b; 1976)

who has included in Phylloceras some taxa hitherto re- garded as Parrschiceras (see discussion under

1960 Phylloceras salina (sic.) Fleming, p 267

1968 Phyllocerm salima Stevens, p 23

264

L O C A L ~ S : New Zealand Geological Survey collections: AGE AND STRATIGRAPHIC HORIZON: Heterian, Ohauan CEI 16: GS5913, Heteri Peninsula, Kawhia Harbour Col- and Puaroan [Early K i e r i d g i a n to Late Tithonian] lected by K.J McNaught CE282,283: 'Waikutakuta Bay' On the southern shore of Kawhia Harbour the species has (= Kiwi Bay; see Fleming & Kear 1960, map 3), Heteri, been found in beds ranging in skatigraphic position from Kawhia Harbour Collected by J C and R.A.S Browne the lower portion of the Ohinerurn (CE2291) CE297, CE332: ?Heteri Peninsula, Kawhia Harbour Col-

lected by J.C and R.A.S Browne CE363 ?Heteri, Kawhia

Collected by & R.A.S Browne CE1211: GS6198, (Fleming& Kear 1960) On thenorthem shoreofKawhia Waikiekie Peninsula Kawhia Harbour collected by J.B Harbour, fragmentary (C128) orjuvenile specimens ( ~ 1 2 7 , Waterhouse CE1229: GS5913 Heteri Peninsula, Kawhia C 1 7 6 CE2499) are known from the Puti Siltstone Harbour Collected byC.A Flerning, D Kear8rI.W Keyes

CE1395: GS6193, coast south ofMairi Point, KawhiaHar-

Collected bv C, A, Flemine U D, Kear I, W, Keves, localities: (i) Ponganui Quany, where it is associated with

~ ~ 1 4 5 1 : ~~1950,?aumatatotara~est~oad, ~ a w h i a ~ o u t h galoi (BOehm), and lower Hetenan Collected by H T Ferrar C ~ 1 6 2 1 : GS6664, halfway up fossils (Purser 1961, P 27; Waterhouse 1978; Challinor Waikiekie Peninsula Collected by H.C Arnold 1955 1979, fig 4); (ii) Two fragmentary specimens (C305, CE2291: GS5912, east side of Totara Peninsula Kawhia C923) and a juvenile (C303) are known from the Huriwai Harbour Collected by A P Mason CE2306 GS5037, Valley, where it is associated with Upper Puaroan

~ o n ~ a n u i Quarry, Onewhero, southwest Auckland Collected (Waikatoan substage) fossils (Locality 650 of Purser 1961,

by A P Mason ~ 2 2 9 9 : GS59133 nofiwestcoastofHeteri ~ 2 9 ) ~ ~ ~ a l i t y 650 (R1316650) is the skatigraphically

Peninsula, KawhiaHarbour Collected by K J McNaught highest ammonite in the New Zealand Jurassic, CE2300: GS5954, west coast ofKowhai Peninsula, Kawhia

Harbour Collected by K J McNaught CE2464: GS7457, In terms ofthe lithoskatigraphy established by Kear (1966, Kairimu R O ~ ~ , west of ~ ~ collected by ~ B C ~ 1987) and Waterhouse (l978), locality 650 lies in the k ~ ~ ~ UP-

Waterhouse CE2506: GS1953 Whakaoirau Road Kawhia Permost 30 m oftheputi Siltstone An associated a m o - South collected by K.J ~ c ~ a u g h t ~ ~ 2 5 2 1 : ~ ~ 5 9 5 1

Heteri Peninsula, Kawhia Harbour Collected by K.J

McNaught CE2558: GS5954, west coast of Kowhai Point,

Kawhia Harbour Collected by K.J McNaught CE2645:

GS6198, Waikiekie Peninsula, Kawhia Harbour Collected

by K.J McNaught 1975 CE2691, CE2694: GS5950, Heteri

Peninsula Kawhia Harbour Collected by M & R Cobb,

1993 CE2703: GS5949, Heteri Peninsula, Kawhia Har-

bour Collected by M & R Cobb 1993 CE2704: GS5949,

Heteri Peninsula, Kawhia Harbour Collected by M & R

Cobb, 1992 CE2716: GS5913, McNaught Shellbed, west-

ern coast of Heteri Peninsula, Kawhia Harbour Collected

by M & R Cobb, 1991 CE2717: GS5913, McNaught

Shellbed, western coast of Heteri Peninsula, Kawhia Har-

bour Collected by M & R Cobb, 1992

University of Auckland collections:

C108: AU 8518, Ohinerurn, Kawhia Harbour Collected by

E.J Searle 1942 C128 Puti Point, Kawhia Harbour Col-

lected by A.R Lillie C147: AU2620, Captain King's,

KawhiaHarbour Collected by E.I Searle C164: AU2632,

coast SW side of Heteri Peninsula, Kawhia Harbour Col-

lected by A.R Lillie C302: AU2664 Sunset Beach Col-

lected by J Fong 1962 C305: AU2667, Huriwai Valley

Port Waikato Collected by D Stanley 1962 C 642, Cap-

tain King's shellbed, Kawhia Harbour Collected by J.A

Grant-Mackie C378: AU8922, Ponganui (= Moewaka)

Quarry, Onewhero S W Auckland Collected by J A Grant-

Mackie et al C1558: AU6414 Whakapirau Road, Kawhia

Collected by J.A Grant-Mackie et al 1972 C923: Huriwai

Valley Port Waikato Collected by PF Ballanceet al C989:

McNaught Shellbed Heteri Peninsula, Kawhia Harbour

Collected by I A Grant-Mackie et al

A large fragment of P salima, ca 150 mm in diameter,

was found by Margaret and Roger Cobb (Featherston) from

an outcrop at the head of Waikutakuta Creek (Fleming &

Kear 1960, Map 3) and another fragment was found in the

McNaught Shellbed Both localities lie within the

Ohineruru Formation

nite, Subplanites huriwaiensis is ofLate Tithonian age (see

p 82); (iii) A whorl fragment (C302) is h o w n from Sunset Beach, where it is associatedwithupper Puaroan (Waikatoan substage) fossils (Locality 636 of Purser 1961, p 28) Judging from the occumences recorded above in the L& calities section, it appears that in the New Zealand se- quences P salima attains an acme of abundance in the Upper Heterian and declines markedly in the Ohauan and Puaroan

Figure 12 Phyllocerassolimo Krumbeck External suture lines

10 mm

slight break of slope at the middle of the whorl sides in

CE1211 simulates in certain lighting a faint spiral bulge

lirae, about halfthe width ofthe interspaces ventrally, but

converging dorsally; not bundled but remaining discrete

and fading almost completely on the inner halfofthe whorl

sides Specimen CE2291 (PI 1, fig l ) shows eight weak

radial folds developed on the whorl sides adjacent to the

apertural end of the shell The folds are spaced some 3

mm apart at their ventral extremity and converge dorsally

The radial folds are restricted to the inner halfofthe whorl

sides, where the lirae, strongly developed on the outer half

of the whorl sides, have considerably faded Similar ra-

dial folds, spaced some 5 mm apart, are shown on a kag-

ment of an outer whorl in specimen CE1229 The sutures

(Fig 12) have long slender lobes and saddles with mainly

tetraphyllic endings, but the folioles throughout the suture

are markedly less phylloid than in most Phylloceratinae

COMPARISONS AND REMARKS: The type specimen of

PhyNoceras salima was one of only two ammonites de-

scription and figures agree exactly with the New Zealand species except for the main lateral saddle-endings, but it

is apparent that on the drawn suture (the last) these are largely worn away and have been 'restored' However as

Dr W.J Arkell observed in his MS notes the distinction between adiphyllic and tetraphyllic lateral saddle depends

on the relative development of the small terminal folioles, which are liable to vary and change with growth This is well shown by Neumay's figures (1871) of sutures of

PhyNoceras smonicum at different growth stages: the diphyllic first lateral saddle of his pl 13, fig 4 has be- come incipiently tetraphyllic in his pl 14, fig 2, and the second and third lateral saddles have also become more complex with growth

(which may be only a compressed variety of the still com-

the stems less deeply incised and the folioles less rounded (cf the variation in shape within the Mexican Callovian

(Burckhardt 1927, pl 1-12) The highly phylloid saddles

of P srmonicum are well shown in Neumayr's figures

(1871, pl 13, fig 4; pl 14, fig 2) of the European types

and also in a Kachh specimen figured by Spath (1927-33,

pl 91, fig 6a-c) Benecke's figures o f the suture o f

Neumayr, 1871, pl 13, fig 3); and the whorls are much

Zittel 1868, pl 7, fig 5 , 6 ) the sutures are barely phylloid,

as in P salima, but much more complex, as was pointed

out by Neumayr, and also the whorl shape is different, with

less abrupt umbilical edge

Although slight differences are apparent, the New Zea-

group of Phylloceratids that populated the margins of the

Tethys in Late Jurassic time Apart from occurring in the

Southern European and Mediterranean regions (eg

Benecke 1865, Zittel 1868, Neumayr 1871, Knvnheck

1905, Wendt 1963, Christ 1960), members of the group

also occur in Mexico (Burckhardt 1906) India (Spath

1927-33), East Africa (Spath 1930); Malagasy (Collignon

1959; Joly 1976) and Indonesia (Boehm 1904, 1907a,h)

LOCALITIES: NewZealand ~ e o l o ~ i c a l Survey collections:

CE115: GS5912, west of Heteri Peninsula, Kawhia Har-

bour Collected by K.J McNaught CE286: 'Waikutakuta'

west of Heteri Peninsula, Kawhia Harbour Collected by

K.I McNaught CE1182: GS6193, Mairi Point, Kawhia

GS9847, 50 metres downstream from suspension bridge,

Hurunui River, North Canterbury Collected by P A

Maxwell CE2518: GS5962, Whakapirau Road, Kawhia

South Collected by G.R Stevensand LW Keyes

University of Otago collections:

OU 15238: Whakapirau Road, Kawhia South Collected

by J.D Campbell

University of Auckland collections:

C1 544: AU 161 4, Heteri Peninsula, Kawhia Harbour Col-

lected by J.A Grant-Mackie et al 1968 C 989: McNaught

Shellbed Heteri Peninsula Collected by J.A Grant-Mackie

et al 1968 C1537, 1538: AU9893, Moewaka(=Ponganui)

Quany Onewhero, S.W Auckland Collected by A.P Ma-

son 1951

University of Canterbury collections:

UCM14: branch of the Sandford Stream (S67.1779) Col-

REMARKS: Four small ammonites, up to 18 mm in diam-

eter, have been collected from the base of the Ethelton

Conglomerate outcropping in the Hurunui River, North

Canterbury (McKellar et al 1962, p 491), and in a neigh-

bouring area (UCM14 above) All represent the same taxon

ated fossils, including hivalves, belemnites and the holotype ofldoceras speighti (Marshall) range in age from Heterian toPuaroan (Stevens 1965, pp 95, 104, Campbell

& Warren 1965; Speden 1975; Stevens 1978b, p 259)

Phylloceras sp., cf salima juv

CE2499, CS6477 southeastern shore platform, Motutara Pe- ninsula, Kawhia Harbour Collected by K.J McNaught University of Auckland Collections:

Bartrum 1944 C303: AU2665 Huriwai Stream, Port Waikato

CE284: GS1940, Te Anga-Kinohaku Road, Kawhia Col-

ninsula, Kawhia Harbour Collected by I.W Keyes CE2657:

1954

University of Auckland collections:

C 149: AU 2622 Kowhai Point, KawhiaHarbour Collected

by E J Searle

tion to lirae as in Phylloceras, blunt ribbing gradually sets

in on venter and outer half of whorl sides Sutures with very slender, diphyllic saddles

RANGE OF GENUS: Sinemurian to Valanginian (Arkell et

al 1957, p 187)

DrsCUSslON: Generic placement of the New Zealand Late Jurassic material identified in the present study as Partschiceras has presented difficulties because of the poverty of material and the absence of diagnostic sutures The New Zealand specimens have a Phylloceras-like conch, with a compressed whorl section and rounded ven- ter The conch is ornamented with fine lirae (as in

of radial plications

Spath (1927-33, pp 35-38) attempted to rationalise the systematics of Phylloceras-like ammonites with regular radial plications and on the basis of differences in orna- ment a n d sutural patterns h e applied the names Portschiceras Fucini, Macrophylloceras Spath and Phyllopachyceras Spath The same systematic scheme was adopted by Roman (1938, pp 15-18) and Basse (1952,

pp 598-599) Arkell et al (1957, p 187) recognised

P a r f s c h i c e r a s and PhyNopachyceras but included Macrophylloceras in Partschiceras

Arkell et al (1 957, p.187) applied the name Parfschiceras

to taxa ranging in age from Sinemurian to Barremian and

Phyllopachyceras to taxa ranging in age from Barremian

to Maastrichtian and a similar position was adopted by

Wiedmann (1962, p 138; 1964, p 229)

The systematics o f the Lias representatives of

Partschiceras were reviewed by Fantini Sestini (1971)

She advocated a broad approach to the recognition of

Partschiceras and doubted the validity of the separation

of Phflopachyceras from Partschiceras Meanwhile, Joly

of Phylloceras and restricted application of the name

Partschiceras to the Liassic ammonites related to

A partschi Stur (= A sfriafocostafum Meneghimi accord-

ing to Fantini Sestini 1971) Joly referred middle and late

Phyllopachyceras and Adabofoloceras requires further

investigation and clarification The deficiencies of the New

Zealand material mean that the present study cannot make

stances a broad view has been taken of the genus

Parfschiceras, similar to that adopted by Kennedy and

Klinger (1977, p 369)

Although the New Zealand material consists of only frag-

mentary and corroded specimens, nonetheless they are very

distinctive when seen in the context ofthe entire New Zea-

land Late Jurassic ammonite fauna and therefore warrant

full taxonomic description

Parfschiceras otekense n sp

Plate 2, figs 2,3, Text-fig 13

HOLOTYPE: CE1188: GS6193, Mairi Ammonite Bed,

coast 12 chains south of Mairi Point, on west shores of

Oteke Inlet, Kawhia Harbour Collected by C.A Fleming

and J.B Waterhouse The species name is derived from

that of Oteke Inlet

LOCALITIES: New Zealand Geological Survey collections:

CEI 188: '36193, Mairi Ammonite Bed, KawhiaHarbour

University of Auckland collections:

C947, 948 Mairi Ammonite Bed, Kawhia Harbour Col-

dle Tithonian]

The Mairi Ammonite Bed, in which the species occurs, is

a unit some 13 m thick situated about mid-way through

D W h H Wb B W U d U

test intact No sutures are visible The whorl shape is high and rather flat-sided (Fig 13), the venter rounded Ornament consists of growth-lines or lirae superimposed

are strongest on the venter and ventral half of the whorl sides However, the plications do not die out towards the

lustrated by Fantini Sestini (1971) but continue, although less prominently than on the venter and ventral flanks, and converge and fuse irregularly in twos and threes at the

adjoining the seam, there is a small flange

AmmoniteBed, coast south ofMairi Point, KawhiaHarbour Ohauan Stage Partially restored whorl cross-section

pered because of the differing interpretations of the gen- era Partschiceras, Phylloceras and Phyllopachyceras, and

Accepting the limitations of the New Zealand material,

P striatocostatum (Meneghini) (= Ammonitespamchi

Stur), fiom the Sinemurian/Pliensbachian of Italy, as

illustrated by Fantini Sestini (1971) For example,

the whorlcross-section and general ornamentation

of P otekense resembles that of the specimen of

P striatocostamm illustrated by Fantini Sestini (1971)

as pl 32, fig la, b In hoth specimens well defined

lirae are developed, superimposed on radial plications

that become accentuated towards the venter However,

in P otekense the plications are more strongly devel-

oped than in P striatocostatum and persist to a greater

degree on the flanks, extending towards the umbilicus

scribed by Rakus (1964,1965) from the Pliensbachian

of Czechoslovakia show a stronger development ofrib-

is still some marked fading of the ribbing towards the

umbilicus, although this may he a result of differential

abrasion of the test

The general character of the test and development of

fig 1,2) from the Callovian of the Crimea, which has

been refigured from the type locality, Kopsel, by de

Tsytovitch (1912, pl 2, fig la-c)

However, P otekense is much more compressed in

viator is not clear Although Wendt (1963) and Elmi

the concept of which he extended to include forms in

the Jurassic as well as in the Cretaceous (cf Arkell et

al 1957, p 187)

douvillei Choffat (1893, p 10, pl 16, fig 3) also ap-

the ribbing largely confined to the venter and fading

on the shoulders Joly (1976, p 139) tentatively as-

(Kudematsch)

Taxa grouped by Joly (1976) under his new genus

Adabofoloceras have gross similarities with P otekense

but in view of the deficiencies in the New Zealand ma-

exact comparisons are difficult

Close similarities are apparent with taxa formerly as-

Macrophylloceras semiplicatum Spatb from the

in both test morphology and ornamentation However the ribbing appears to be stronger, more regular and more closely spaced in P otekense In this respect

P otekense may be closer to the Tithonian representa-

MacrophyNoceras semiplicamm Spath has been re-

kudernatschi (von Hauer)

(5) Concluding statement

As indicated by the preceding discussion, it is appar- ent that in its morphological features P otekense re- sembles taxa assigned by various authors to

Phylloceras, Partschiceras, Adabofoloceras, Macrophylloceras and Phyllopachyceras and that reso-

lution of generic placement must await the discovery

of additional material, preferably with sutures pre- sewed

Nonetheless, on balance the general aspects of

P otekense appear to be closest to taxa identified

Macrophylloceras, i.e., sh.iatocostatum Meneghini, monymum Haas, and semiplicatum Spatb If a broad

ble to that of Arkell et al (1957, p 187); Wiedmann (1 962, 1964), Howlett (1989, p 9) and Fantini Sestini (1971), assignment of the New Zealand material to

Partschiceras is favoured

P otekense strongly resembtes Spath's reduced figure

known New Zealand locality (Natural History Museum, London, C.5201a) (PI 2, figs 6,7) On comparing the two specimens, however, P otekense is seen to differ in two details of the ribbing On the ventral shoulders of

P otekense the ribbing passes straight over the venter

whereas in Spath's specimen it is slightly projected; and

on the umbilical edge in P otekense the ribbing shows the bundling clearly whereas in Spath's specimen the ribbing dies out at this point Spath's specimen is also much larger

The matrix of Spath's unlocalised specimen, as he noted (1923, p 287) is a hard dark green ferruginous rock Al- though in the absence of confirmatory evidence the speci- men must remain in the unlocalised category, it must none- theless be noted that the matrix of Spath's specimen is remi- niscent of some ofthe more indurated parts of the Captain King's Shellbed This distinctive unit, of Heterian age, has beentraced by Francis (1 977; see also Challinor 1979,

pp 271-272) from Totara Peninsula, Kawhia Harbour

1959, p 785) At hoth Kawhia and Awakino, collections

Ongley (1923, p 24) from Awakino] Thus there is the strong possibility that Spath's specimen may have origi- nally come fiom the Heterian It is of interest, therefore,

to note that a Parischiceras (P snigoceriforme n sp.) is

known from Heteri Peninsula, Kawhia Harbour, some 500

m above the Captain King's Shellbed Additionally, Spath's

specimen h&s the same matrix as an unlocalised

Lytoceras (Spath 1923, p 293) that is probably a frag-

ment of L, taharoaense Stevens, also known from the Cap-

tain King's Shellbed (Stevens 1985a, pp 167-168)

Parischiceras strigoceriforme n sp

Plate 2, figs 4,5, 8, Text-fig 14

1960 Partschiceras Fleming, p 267

1968 Parfschiceras spp (pars.) Stevens, p 22

1974 Partschiceras spp (pars.) Stevens, p 746

1978a Parfschiceras (pars.) Stevens, p 225

Harbour

LoCALrrIEs: New Zealand Geological Survey collections:

CEI 175 and CE1393 (supposed nucleus): GS6193, Mairi

Ammonite Bed, Oteke Inlet, Kawhia Harbour Collected by

northeast coast of Heteri Peninsula, Kawhia Harbour Col-

lected by K.J McNaught CE2502: GS6475, East side of

Puti Point, Kawhia Harbour Collected by G.R Stevens and

I.W Keyes

University of Auckland collections:

C1039: Mairi Ammonite Bed, Kawhia Harbour Collected

by J.A Grant-Mackie et al 1967 C983: South of Kowhai

Point, Kawhia Harbour Collected by J.A Grant-Mackie et

al 1965

Ohauan and Lower Puaroan (Mangaoran) [Early

Kimmeridgian-Middle Tithonian]

occurs in beds ranging in stratigraphic position from the

W a i h t a h t a Siltstone up to about the middle of the Puti

Siltstone (exposed at Puti Point)

DIMENSIONS (in mm):

D W h H Wb B W U d U

CE 1230 78* 45 57.69 32 41.02 71.11 7.0 8.97

most of the test preserved, the other side destroyed by

weathering Sandpapering has revealed extremely com-

plex phylloid sutures, but none are exposed clearly enough

for figuring or to enable the saddles to be described as di-

or tri-phyllic On the outer half of the last whorl the rib-

bing and plications are as in P oiekense However, the

inner half of the whorl is unribbed and forms a convex

bulge, separated from the outer half by a broad medial-

Peninsula, Kawhia Harbour Hererian Stage Drawing to show spiral groove on internal mould

rangement is suggestive of Strigoceras (cf d70rbigny

1845, pl 117; Wendt, 1963, pl 17, fig.3); hence the deri- vation of the specific name The whorls are thicker than

in F1 neoviaior, but precisemeasurements cannot be taken Specimen CE1175, from the Mairi Ammonite Bed, is smaller, incomplete and damaged, but shows the essential specific characters The supposed nucleus, CE1393 (PI

2, fig 8), is 24 mm in diameter In itthe bulge on the inner part of the whorl sides, although subdued, is nonetheless already present

much shallower median lateral furrow exists in a closely allied specimen from the Oxfordian of Kwa Dikwaso in

Tanzania, identified as Phylloceras aff subobtusum

(Kudernatsch) (Arkell 1956, p 328) although the type horizon of that is Bathonian (see Popovici-Hatzeg 1905,

pl 1(9), fig 8,9) Recent authors (e.g see synonomy in

Joly, 1976, p.138) have regarded subobtusum as a

Partschiceras, but Joly (1976) has assigned it to his new

genus Adabofoloceras

Specimen C1039, from the Mairi Ammonite Bed, is 67

mm in diameter, with one side severely weathered but with some areas of test preserved on the other side As in the holotype, although fragments of complex phylloid sutures are visible, they are not coherent enough for description

As is also shown in the holotype, the ornament consists of simple straight ribbing confined to the venter and outer half of the whorl side The inner half ofthe whorl side is unribbed and is separated by a smooth and broad medial- lateral furrow

cf Parischiceras sp indet

New Zealand Geological Survey collections:

CE1663: GS5941, TotaraPeninsula KawhiaHarbour Col-

lected by G.R Stevens

Subfamily CALLIPHYLLOCERATINAE Spath, 1927

Genus CaNip11.yIloceras Spath, 1927

GENERIC DIAGNOSIS (Arkell et al 1957, p 189): Smooth,

involute, compressed with rounded venter and periodic

sigmoid consmctions on internal mould, with or without

corresponding flares on ventral half of test; surface also

with lirae, as in Pln~lloceras First and 2nd lateral saddles

usually triphyllic, others diphyllic

RANGE OF GENUS: Hettangian to Albian (Arkell et al 1957,

p 189)

Cal1iph)~lloceras empedoclis (Gemmellaro)

Plate 3, figs 1-4, PI 4, figs 1-5 Text-figs 15-17

1872 Phylloceras empedoclis Gemmellaro, p 3 l, pl 9, fig l,

2: (1877) p 179, pl 16, fig 4

191 1 Phylloceras sp (pars) Boehm, p 17 (not Marshall's

specimen of Phylloceras kawhiae)

1960 CallipAylloceras empedoclis (Gemmellaro); Fleming &

LocAL~ES: New Zealand Geological Survey collections:

CE285: Concretion on beach, MotutaraPoint, Kawhia Har-

bour Collected by R.A.S Browne, 1943 (fragment of outer

whorl of specimen Cl 12; see below) CE366: Unlabelled,

hut probably Motutara Peninsulaor Puti Point Kawhia har-

bour (same matrix and preservation as CE1452) Collected

by R.A.S Browne CE391: Te Ahuahu (Lemon Point),

Kawhia Harbour Collected by P Marshall CE1452:

GS522, north side of Kawhia Harbour (probably Motutara

Bluff see McKay 1884, p 144) Collected by A McKay

CE2305: GS5958, Puti Point, Kawhia Harbour Collected

by A.P Mason CE2457: unlocalised specimen, exNational

Museum collections The specimen has an old Colonial

Museum paper label inscribed with a letter that corresponds

to Hector's category for "Oolitic" (i.e Upper Jurassic) (Hec-

tor 1886a) The lithological characteristics of the specimen

are comparable to those ofconcretions derivedeom thePuti

Siltstone, and found commonly on the shore platform in the

vicinity of Puti Point and Motutara Peninsula, KawhiaHar-

bour It is therefore presumed that the specimen originally

came from this area

University of Auckland collections:

C112: Motutara Point, Kawhia Harbour Collected by R

A.S Browne [During this study it was found that specimen

CE 285 in the R.A.S Browne Collection, NZ Geological

Survey, was a fragment of the outer whorl of specimen C1 12

in the Auckland University collections CE285 has been restored to its original position as part ofC112] C128: Puti Point, Kawhia Harbour Collected by A.R Lillie (2168: Puti Point, Kawhia Harbour Collected by M.H Battey 1942 C177: Puti Point KawhiaHarbour Collected by R.N Broth- ers C260: AU2663, Huriwai Stream, Port Waikato Col- lected by B.H Purser C372: Motutara Peninsula Col- lected by E.] Searle C375: Puti Point, Kawhia Harbour Collected by M.H Baney C974 C1040: Mairi Ammonite Bed, Kawhia Harbour Collected by J.A Grant-Mackie et

al 1967 C1046: Puti Point, KawhiaHarbour Collected by J.A Grant-Mackie et al 1967

AGE AND STRATGRAPHIC HORIZON: Upper Ohauan and Lower Puaroan (Mangaoran) [Middle Tithonian]

In the Kawhia section the species occurs in beds ranging

in stratigraphic position from the middle of the Kinohaku Siltstone (e.g CE391, C974, C1040) up to the middle of the Puti Siltstone (e.g CE1452, CE2305, C1046) (Fleming

& Kear 1960)

DIMENSIONS (in mm):

CE366(n) 104 56 53.8 30* 28.8 53.5 9.0 8.6 CE391 101 56 55.4 36 35.6 64.2 5.5 5.4

CE 1452 230 136 59.1 61* 26.5 44.8 10.5 4.5 CE2305 88* 47 53.4 24 27.2 51.0 7.5 8.5 CE2457 174 100 57.0 54 31.1 54.0 8.0 8.0

C 112 200 113 56.5 61 30.5 53.9 9.5 4.7

C 1046 (n) 180' 110 61.1 55 30.5 50.0 8.0 4.4 (n) =(nucleus) *estimate

DESCRIPTION: Specimen CE 2457 appears to be septate

to a diameter of 174 mm The septate conch is surrounded

by the crushed remains of the body chamber, extending outwards to a possible diameter of 263 mm A similar situation occurs in specimen C1046, which appears to be septate to a diameter of 180 mm, but is surrounded by the remains of crushed body chamber to a diameter of about

250 mm Specimen CE 1452 has a diameter of 230 mm, but it is not possible to be sure how much of the conch is body chamber The diameters of these three New Zealand specimens fall into the size range of the wholly septate

Sicilian C empedoclis (Gemmellaro), and the probably

synonymous C giganteum Toula (Toula 1907, pl l l , pl

1, fig 2), from near Vienna Both came from the Early Kimmeridgian Acanthicus Beds

Although CE366 is septate to a diameter of 104 mm, it is associated with a fragment of a possibly septate outer whorl, suggesting that its original size was comparable to that of CE1452 (i.e D=230 mm) C112 is septate to a diameter of 200 mm C372, representing a quarter seg- ment of a whorl, may have been septate to a diameter of some 300 mm

In most specimens so much test is present that sutures can only be seen intermittently and very incompletely Rea-

sonably complete sutures are present, however, in CE 391,

CE2305, C168, C1046 and C372 (Fig 15) As seen in

many phylloceratids (e.g Kullmann and Wiedmann 1970,

fig 5), theventral saddle is markedly spatulate, even when

the suture is rather worn, as in Fig 15C The lateral (L)

and umbilical (U) lobes are sharply differentiated The

umbilical lobes U, and U, are followed by between 3 and

5 smaller umbilical lobes, decreasing progressively in size

towards the umbilical seam These smaller lobes appear

to he a product of the progressive proliferation of the U,

more or less symmetrical lobe splitting at the umbilical

seam which is a characteristic o f phylloceratids,

lytoceratids and desmoceratids (Kullmann and Wiedmann

1970 p l I) The partial sutural formula, as seen in the

sutures illustrated in Fig 15A-C, can therefore he expressed

The test is omamented with fme thread-like lirae, that on

interspaces The lirae are straight or very slightly curved, pass unchanged across the venter, and converge dorsally, but remain discrete and are not bundled

There are about six or seven shallow constrictions per whorl, visible only on the internal cast The constrictions are almost straight, being only very slightly sigmoidal (Fig 16) The whorl cross-section is oval (Fig 17)

septate, and the New Zealand specimens agree perfectly

in proportions with the measurements tabulated for

empedoclis, and also with the number of constrictions (six

to eight), their shallowness, and the very fine ribbing The other prior-named and closely allied species kom the Early

Figure 15 Coliiphyiioceros empedoclis (Gemmellaro) External suture lines

A (upper) CE 2305 Puti Point Kawhia Harbour Puaroan Stage Finely preserved suture line at diameter (D) of ca 62 mm

B (centre) C 1046, Puti Point Kawhia Harbour Puaraan Stage Suture line at diameter (D) of 129 mm

C (lower) C 112, Motutara Point, Kawhia I-labour Puaroan Stage Rather worn suture line at diameter (D) of 143 m

25

Kimmeridgian Acanthicus Beds, C benacense Catullo (see

Neumayr 1871, p 336, pl 15, fig 3a-c), differs by its larger umbilicus (forming ooe percent of the diameter), its deeper and fewer (five) constrictions, and more distant ribbing

As well as having been recorded fiom areas in southern Europe (Austria, Switzerland, Italy, Sicily), C benacense

has also been recorded kom the Early Kimmeridgian of Kachchh (Waagen 1873-1875; Spath 1927-31) and Mala- gasy (Besairie 1932, 1936; Collignon 1959; Joly 1976)

Calliphylloceras sp indet

CE2292: GS5037, Ponganui Quarry, Port Waikato Col- lected by A.P Mason CE2507: GS2503, Pomarangei Road, tlerangi Range Collected by H.T Ferrar, 1928 CE2723: GS5941, Oraka Bay, east coast of TotaraPeninsula Kawh~a Harbour Loose on shore platform Collected by Margaret

& Roger Cobb 1992 CE2730: GS5941, Oraka Bay, east coast of Totara Peninsula, Kawhia Harbour In cliffs behind shore platform, collected by Margaret & Rober Cobh 1993

Figure 16 Callip~iloc~ros emperloclrs (Gemmellaro) CE 2305, AU6414, Whakapirau Road Kawhia South Collected by

Puti Point Kawhia Harbour Puaroan Stage Diagram J.A Grant-Mackie et al 1972 AU73 13, OrakaBay, Kawhia showing constrictions developed on the internal mould Harbour Collected by J.A Grant-Mackie et al 1980

Figure 17 CalliphyNoceras empedociis (Gemmellaro) Whorl cross-sections

A (left) CE 391 Te Ahu Ahu, Kawhia Harbour Ohauan Stage

B (centre) C 1046, Puti Point, Kawhia Harbour Puaroan Stage

26

AGE AND STRATIGRAPHIC HORIZON: Heterian (Early

Kimmeridgian)

T h e specimens listed above have been collected from

Heterian localities correlated with t h e Oraka Sandstone

and the lower part o f t h e Ohinerurn Formation Although

t h e specimens are imperfectly preserved, they appear t o

represent a Calliphylloceras that is either virtually smooth-

shelled or ornamented with extremely fine hair-like lirae

that are readily removed b y corrosion or diagenetic altera-

tion

G e n u s HolcopltyNoceras Spath, 1927

GENERIC DIAGNOSIS (Arkell et al 1957, p 189): Resem-

bles Calliphylloceras but constrictions affect test as well

as internal mould and are more acutely sigmoid, linguate,

o r angular, and the outer half of the whorl is ribbed Sad-

dles o f sutures diphyllic except i s t lateral saddle, which

becomes triphyllic in later forms

RANGE OF GENUS: Bajocian-Aptian (Arkell et al 1957, p

1910 Phylloceras maloyan~rm Boehm (parrim); Dacque, p 6,

pl 1, fig la, b only

non 1907 Pl~ylloceras moIa,vanum Boehm, p 78, pl 12, fig 7,

pl 13, 14, 15, fig 1-2, text-fig 24-26

1923 PhyNoceras cf polyolcum (Benecke); Spath, p 296

1925 Phylloceras mesolcum Dietrich, pl l , fig 4, 5

1927 Holcophylloceras a R polyolcvm (Benecke); Spath, p

1959 HolcophyNoceraspoIyo(cum (Benecke), Collipnon PI

96 fig 365; PI 97, fig 367

1960 Holcophylloceraspolyolcz~rn (Benecke) (parrim):

Fleming & Kear, pp 24 (CE924 only), 28,32,41

1960 HolcophyNoceras (partim); Fleming, p 267

1976 Holcophyllocerospolyolcum (Benecke); Joly pp 255-

257, PI 24, fig 1.4; PI 25, fig l: PI 26, fig I, PI 54,

fig 5.7; PI 55, fig 1

1976 Holcophylloceras mesolcum (Diewich); Joly pp 251-

254, PI 23, fig 2, 4,7: PI 28, fig 1.2, 3, l l : Fig, 54,

fig 2, 6: PI 55, fig 4; PI 56, fig 8

1978a HolcophyNocerospolyolcum (Benecke); Stevens, p 225

1978 Holcophylloceraspolyolcum (Benecke); Stevens &

Speden, p 264

LOCALITIES: N e w Zealand Geological Survey collections:

C E l l 5 (fragment): GS5912, point west of Heteri Penin- sula Kawhia Harbour Collected by K.J McNaught (note misprint in Fleming& Kear 1960, p.28: GS1912=GS5912) CE279: Hineruru, Totara Point, Kawhia Harbour R.A.S Browne (in MS notes) identified this specimen (from an old Geological Survey collection) as Phylloceros kawhiae Marshall and commented: "This specimen in all probability came from Hineruru usually referred to as either Totara Point, which has no marine fossils but instead obscure plant re- mains, or to Captain Kings, which is too indefinite" CE280: GS1940, Te Anga-Kinohaku Road, Kawhia Collected by 1 Williamson CE331 (incomplete giant specimen): Puti Point, Kawhia Harbour Collected by L.C King and K.J McNaught

1931 CE924 (fragments of a large specimen): GS5941, coast due east of Captain King's, east coast of Totara Point Kawhia Harbour Collected by K.J McNaught CE1678, CE2504: GS5941, Oraka Bay, east coast of Totara Point, Kawhia Harbour Collected by G.R Stevens CE2724: GS5941 Oraka Bay east coast of Totara Point Kawhia Harbour Loose on shore platform Collected by Margaret and Roger Cobb 1991

University o f Auckland collections:

C108: Ohineruru, Kawhia Harbour Collected by E 1 Searle, 1942 C l 11: Captain King's, Ohineruru, Kawhia Harbour Collected by J.A Bartrum C134: near Captain King's, Kawhia Harbour Collected by I.A Bartrum and E.J Searle 1930 C138-9: Ohineruru, KawhiaHarbour Col- lected by E.J Searle C140: Ohinerurn, Kawhia Harbour Collected by J.A Bartrum

R.A.S Browne mentioned in MS notes held in NZ Geologi- cal Survey archives that the Auckland University specimens listed above as coming from "Ohinerurn" and "near Captain King's" came from two localities: (i) from the reefs exposed

on the foreshore at Ohinerurn (= Captain King's Shellbed and basal Ohineruru Formation, cf Fleming & Kear 1960 Fig 9); (ii) "from the cliffs below Whitiora's house" (= Cap- tain King's homestead; Fleming&Kear 1960, p 25), "some

50 yards north along the beach from the reefs at Ohinerurn" (=upper Oraka Sandstone of Fleming & Kear 1960 p.24) Natural History Museum collections, London:

Trechmann Collection, C24852 Kowhai Point, KawhiaHar- bour Recorded by Spath (1923 pp.296-297)

R A S Browne Collection:

In MS notes held at NZ Geological Survey, R.A.S Browne recorded two specimens that now appear to be lost: (i) From Ohineruru: a septate fragment, 96 mm in diameter showing two chevron-shaped constrictions (ii) From Kowhai Point:

a septate conch, 190 mm in diameter with 6 chevron-shaped constrictions and fine ventral ribbing

AGE AND STRATIGRAPHIC HORIZON: Heterian t o Lower

P u a r o a n ( M a n g a o r a n ) [Early Kimmeridgian-Middle Tithonian]

In the Kawhia Harbour succession the species has been found in beds ranging in stratigraphic position from the upper part o f the Oraka Siltstone u p t o the lower portion

of the Puti Siltstone (Fleming & Kear 1960)

DIMENSIONS (in mm):

BMNH

C24852 178 88 49.4 30* 16.8* 34.1 18 10.1

whorl cross-sections (Fig 18) tine ventral ribbing and

about 6 to 12 constrictions, according to size The number

sections (partially restored)

A (left) BMNH C 24852 Kowhai Point, Kawhia Harbour

Ohauan Stage

Heterian Stage Rather worn nucleus

of constrictions cannot be counted reliably over a whole

whorl on any of the New Zealand material available The

large incomplete Puti Point specimen (CE33 1; PI 6, fig

1) represents less than half a whorl from a growth stage at

about 200 mm diameter, and there are six constrictions,

but some are blurred and difficult to locate It agrees well

Kimmeridgian Septarian Marls of Tanzania, (Aitken Col-

lection, Sedgwick Museum, Cambridge), and with

?Hinemru, Totara Peninsula; Kawhia Harbour Heterian

Dietrich's figures (Dietrich, 1925, pl.1, figs 4 3 Speci- men CE279, although much worn, shows that the second lateral saddle is pronouncedly triphyllic and all the other

The umbilicus is deep and steep-sided and its width is 10%

of the diameter of the conch

The overall morphology agrees very well with the speci-

96, Fig 365) from the Early Kimmeridgian of Malagasy

251-254) from the Early Kimmeridgian of Malagasy and

by Spath (1930, PI.1, fig 2 a-d) from the Kimmeridgian

the number of constrictions increases with size of shell, but Dietrich (1925, p 9) considered that "in the present stage of systematics the number of constrictions must be used for distinguishing species" The sole distinction of

diameters At the same time he states that it is a giant

which case it would always have fewer constrictions than

polyolcum at corresponding sizes Spath (1930, p 24, pl

same time admitted that "it is connected by numerous tran-

Figure 21 shows the numbers ofconstrictions on the Mom- basa specimens figured by Spath and Dacque plotted on a

Diameter (in mm)

Figure 20 Holcophylloceraspolyolntm

(Benecke) Internal mould BMNH

C 24852 Kowhai Point, Kawhia Harbour Ohauan Stage Simplified sketch t o show the pattern of constrictions developed on the internal mould

A Tanzania specimens (Dietrich's table, 1925 : 9) Mombasa specimens

O (Spath 1930, p1.1 figs.2a-c) Mombasa specimen (Dacque 1910, pl.1, fig.1) European polyolcum

(Neumayr 1871 : 342) European polyolcum

X (Benecke 1865, p1.8)

Figure 21 Holcophyllocerospolyolcum (Benecke) Graph comparingthe number of constrictions per whorl in specimens described

by Diehich (1925), Spath (1930), DacquC (1910), Neumayr (l871), and Benecke (1865)

29

graph beside those for the Tanzanian mesolcum derived ably either locality f 673 or f.674 ofFleming& Kear (1 960,

this graph it is clear that mesolcum falls in synonymy, a

of P kawhiae probably came from a marine intercalation

in the otherwise non-marine Urawitiki Measures and is

p 31

thus comparable in stratigraphic setting (and perhaps in

cannot be sustained, for large Calliphylloceras demidofl

In his MS notes, R.A.S Browne states that he had been (Rousseau) occw in the Oxfordian of the Jura (Sedgwick

Museum Collections, Cambridge) and even as far north as

Phylloceras kawhiae and its loss has been confirmed by

Kudernatsch in the Late Callovian (Stevens 1987)

provide a description, the only record is Marshall's photo-

specimen (about 125 mm in diameter) illustrated in his pl

14a The same plate included illustrations of what are

now recognised as the ammonite Aulacosphinctoides

brownei and a large phragmocone of the belemnite

Hibolithes arkelli - both typical taxa of the Puti Siltstone

exposed at Puti Point, Kawhia Harbour Furthermore, the

link with Puti is reinforced by Marshall's statement (l909

in the Kawhia Harbour"

Although Boehm (1911, p 17) and Thomson (1913, p

39) noted the lack ofaccurate locality data for P kawhiae,

(Spath 1923, p 295; Manvick 1953, p 114) However, in

MS notes on PhyNoceras kawhiae held at the New Zea-

land Geological Survey, R.A.S Browne states: "The origi-

nal specimen described by Marshall and mentioned with

Te Puti specimens was collected by the writer in January

1905 from the outer coastal cliffs just south of Beacon

Rock, i.e the South Head of Kawhia Harbour"

In another part ofthe same MS notes, R.A.S Browne has

stated that the locality was southwest, rather than south of

Beacon Rock, and was "near Te Maika" Elsewhere in his

MS notes Browne writes (with reference to Phylloceras

kmmhiae): "This was not found at Te Puti, but was picked

up on a beach below the cliffby one ofus (RASB) in 1907

on the west coast of Te Maika Peninsula, north of Umroa

Point"

In a letter to Dr J Marwick, dated 19/10/1945 Browne

Rock at Te Maika, not Te Puti"

On various manuscript sketch maps held at New Zealand

con Rock" the point due north ofTe Maika (Opapaka Point

Admiralty Chart BA 2524 and by the geological map in

graph and a drawing of the suture that was based on the photograph

Spath (1927, p 57) assigned Phylloceras kawhiae to

Holcop~lloceras, and this assignment was followed by Marwick (1953, p 114) However, the exact generic place- ment remains unclear, as Marshall's photograph shows constrictions that are perhaps too straight for

Holcophylloceras and might agree with those o f

Calliphylloceras Although the number of constrictions

is uncertain, there are probably six or seven, but two of these could be breaks The specimen is about 125 mm in diameter and wholly septate It is so deeply weathered that Marshall's drawing ofthe sutures is misleading; moreo- ver, some details of saddle endings visible on the photo- graph belie the drawing and show it to be extremely inac- curate

Holcopl~ylloceras sp., cf polyolcum (Benecke)

C129: Kowhai Point Kawhia Harbour Collected by E.J Searle C134: AU2784 near Captain King's, Hinemru, KawhiaHarbour Collected by E.J Searle and J.A Bartrum C147: Captain King's, Hineruru, KawhiaHarbour Collected

by E.] Searle 1942 C258: Maraetae Stream, Wlkato South Head Collected by B.H Purser, 1952 AU6420, Orakq Kawhia Harbour Collected by J.A Grant-Mackie 1975

Holcoplrylloceraspassati (Boehm) masoni n subsp

Plate 6, figs 4 , 5 ; Plate 7, figs 1,2; Plate 8, figs 1-7; Plate