DSpace at VNU: The genus Cycas (Cycadaceae) in Vietnam

Microsporangiate cones up to 20 cm long, 5 cm diam.; plants acaulescent; leaves distinctly keeled opposing pinnae inserted at 90-130 ~ on rachis .... Lateral spines on megasporophylls di

The Botanical R e v i e w 70(2): 134-193

The Genus Cycas (Cyeadaceae) in Vietnam

K E N D HILL

National Herbarium of New South Wales Royal Botanic Gardens Sydney 2000, Australia

HI~P T NGUYEN

Institute of Ecology and Biological Resources Nghia Do, Cau Giay, HanoL Vietnam

AND

P r t ~ q K L o c

Department of Botany University of Science, VNU Thanh Xuan, HanoL Vietnam

I Abstract 134

II Introduction 135

III Generic Concepts 135

IV Species Concepts 136

V Hybridism 136

VI Conservation 137

VII Taxonomic Treatment 137

VIII Species Known from China That May Be Expected to Occur in Vietnam 188

IX Doubtful and Excluded Names 190

X Acknowledgments 191

XI Literature Cited 191

I A b s t r a c t

The genus Cycas is revised for Vietnam Twenty-four species are enumerated, nine o f t h e m described as n e w (C aculeata, C brachycantha, C collina, C condaoensis, C pachypoda,

C dolichophylla, C fugax, C hoabinhensis, and C tropophylla) Descriptions o f two Chinese species k n o w n to occur close to the China-Vietnam border are also provided A n e w combina- tion is m a d e for C bifida (formerly C rumphii vat bifida) The species are placed within an infrageneric classification previously outlined Distribution o f all taxa is m a p p e d , and a k e y to species is provided Illustrations are p r o v i d e d for n e w and poorly k n o w n taxa w h e r e adequate

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Issued 03 September 2004

9 2004 The New York Botanical Garden 134

material has been available Previous reports of C circinalis and C rumphii from Vietnam are discussed Lectotypes are designated for C balansae, C chevalieri, and C elongata, and a neotype is designated for C pectinata

II Introduction

The genus Cycas was first recorded from Vietnam by de Loureiro (1793), with his descrip- tion of the new species Cycas inermis, based on collections he had made in Cochin China (southern Vietnam) in 1787 Although the third species of Cycas to be described, C inermis

has at no stage been properly understood Since that date, eight additional taxa have been described as new in the catalog of the flora of Vietnam The first of these were C tonkinensis

and C bellefontii, described by Linden and Rodigas (1885, 1886) Both were described from living plants in cultivation that had been collected in Tonkin (northern Vietnam), and no her- barium material was preserved (see doubtful and excluded names below) Warburg described

C balansae from near Hanoi in 1900, and Thiselton-Dyer described C micholitzii from Annam (central Vietnam-Laos) in 1905 Finally, Leandri described C chevalieri from northern Viet- nam and C pectinata var elongata from southern Vietnam in 1931 Taxa previously known from other areas that have also been recorded from Vietnam are C pectinata Buch.-Ham and

C siamensis Miq The names C circinalis L and C rumphii Miq have at different times been wrongly applied to Vietnamese taxa Other names misapplied to plants from Vietnam have been C undulata and C miquelii (see excluded names, below)

The comprehensive account of the genus by de Candolle (1868), recorded only Cycas inermis

from the region of Vietnam, largely on the basis of the notes published by de Loureiro De Candolle had also followed Miquel (1851) in misapplying the name C inermis to specimens of

C revoluta (see below) Pilger (1926) recorded only C siamensis and C micholitzii from Vietnam Schuster (1932) included C tonkinensis in C circinalis var undulata, but also in- eluded material of the C rumphii complex from the Marianas, together with material from Vietnam, in a confused concept Schuster also recognized C siamensis and C michoBtzii from Vietnam, but then held C inermis and the quite unrelated C balansae as subspecies of

C siamensis Leandri (1931) had added C immersa to the Vietnam catalog, and subsequently Schuster correctly placed C immersa in the synonymy of C siamensis (in subsp, siamensis

sensu Schuster), although he included a number of unrelated species in the other subspecies he erected within C siamensis

The regional account by Leandri (1931) listed 10 species occurring in Vietnam but misap- plied the names Cycas circinalis, C rumphii, and C immersa Ho and Duong (1960) recorded only 7 species but again misapplied the three names above Ho later (1991) added an eighth species, C inermis, again misapplying the above names and the latter name as well Hi~p and Vidal (1996) recorded 8 species, correctly placing C immersa in the synonymy of C siamensis

but otherwise followed the same misapplications (discussed below under relevant species) More recent studies have gradually shown that the cycad flora of Vietnam is substantially richer in fact, probably the richest of the region (Hi~p & Loc, 1997, 1999)

IlL Generic Concepts

The recently described genus Epicycas (de Laubenfels & Adema, 1998) is herein placed in the synonymy of Cycas When characters that are inconsistent are excluded, the new genus is defined solely on the possession of a bulbous underground base However, even this character

is neither wholly consistent within species nor restricted to the species placed in the new genus Moreover, of the species placed within the new genus, a number have what are clearly sister

136 THE BOTANICAL REVIEW

species that were left in the genus Cycas; for example Cycas siamensis and C elongata (both placed in Epicycas) are closely allied to C pectinata, and C taiwaniana is close to the group placed in Epicycas tonkinensis (see excluded species below) Grouping characters (or synapo- morphies) supporting these relationships are discussed below under the relevant sections

IV Species Concepts

The genus Cycas shows a complex geographical replacement pattern throughout its range, often with many closely related entities Although these taxa are often similar in many respects, the homoplasy evident in the defining characters does not always allow unequivocal aggrega- tion into groups that could be treated as species with subordinate subspecies In order to satis- factorily separate and recognize groups of populations that show real, albeit sometimes small, differences, these groups are treated herein as distinct species This rather narrow view of species is considered preferable to the arbitrary submerging of these recognizably distinct and true-breeding groups of populations into broader and less meaningful "species" and the conse- quent loss of information on the real diversity of these plants

Species definition is complicated by the variability of some of the characters that have been traditionally used to separate taxa Development of spines on petioles is often variable within populations and often changes with age in most taxa Microsporophylls vary consider- ably in size and shape from base to apex of the cone; in particular, the apical spine is reduced

or absent on the lowermost sporophylls, gradually increasing in size toward the apex or to- ward the center of the cone (see also Amoroso, 1986) Megasporophylls also vary, often widely, in size, shape of lamina, and number of ovules This can depend on their position within a growth flush, the first and last produced often being markedly smaller and less elaborate than those in the center

Because many herbarium collections are fragmentary, incomplete, and often sterile, many characters are often not present or recorded Comprehensive field study is thus essential to the understanding of the ranges of variation and of characters that distinguish taxa All species discussed herein have been examined in the field

V Hybridism

The problem of hybridism in Cycas was introduced elsewhere (Hill, 1992, 1996) The lack

of pollinator specificity, when combined with the apparently weak inherent fertility barriers, results in the major reproductive barrier between Cycas species in nature being geographical separation Natural populations of Cycas species are usually widely separated geographically, and some breakdown of reproductive isolation would therefore be expected where different species have spread to within pollination range of each other

A number of natural occurrences are postulated to be of just such hybrid origin These are morphologically intermediate between the putative parent species and, in the cases of postu- lated hybrid swarms, show the high degree of variability to be expected from Mendelian segre- gation in the second and later generations Hybrids and hybrid or intergrading populations have been recorded from throughout the range of Cycas, wherever different species grow in relatively close proximity Examples from Vietnam include intergradation between C dolicho- phylla and C.ferruginea east of Thai Nguyen, between C collina and C dolichophylla west of Moc Chau, and between C dolichophylla and C bifida west of Thai Nguyen (all are cited below under the first species of the pair listed)

VI Conservation

Populations of many Asian species appear to have declined, sometimes dramatically, over the past century However, there is no comparative data to support this impression, and evi- dence for the decline is largely anecdotal and circumstantial Several causative factors for this decline can be observed in action today, however, even though quantitative data on the effects are not available Two principal threats to cycads exist in Vietnam at present, habitat loss and selective removal of plants from the wild for trade or utilization Some but not all species occur

in reserved areas already proclaimed, but enforcement within these areas is sometimes diffi- cult There is, however, a growing interest in habitat and species conservation within Vietnam, and additional reserved areas are being evaluated and declared

Only one Vietnamese species, Cycas micholitziL was listed in the now out-of-date (for this

region) IUCN 1997 Red List of Threatened Plants (Waiters & Gillet, 1998) Species treated below are allocated provisional conservation status codes under the new coding system de- vised by the IUCN (IUCN, 1994) Conservation status of all species is summarized in Table I

VII Taxonomic Treatment CYCAS L., Sp PI.: 1188 1753

LECTOaWPE: Cyeas circinalis L.; designated by Stevenson in Jarvis et al (1993)

Dioecious palm-like shrubs with aerial or subterranean, pachycaulous, cylindrical stems

clad with persistent leaf-bases Leaves loosely pubescent when young, pinnate, spirally ar-

ranged, produced in seasonal growth flushes interspersed with cataphylls, lower pinnae often reduced to spines Longitudinalptyxis erect or rarely reflexed, horizontal ptyxis circinate Pin- nae with a single thick midrib and no lateral veins; stomata confined to abaxial surface in most

species; individual ptyxis involute Trichomes transparent, branched or simple Mierosporo- phylls aggregated into determinate cones and bearing numerous microsporangia (pollen sacs)

on abaxial surfaces, with a simple sterile apex, which is often produced into an upturned spine; microsporangia opening by slits; pollen cymbiform, monosulcate Megasporophylls spirally

arranged in an indeterminate terminal rosette with the central axis continuing vegetative growth

Ovules two to many (rarely one), marginally inserted on the stipe and directed obliquely out-

ward ("ascending"); sporophyll apically dilated into a pinnatifid, pectinate, toothed, or entire lamina Seeds with a yellow, orange, or brown fleshy outer sarcotesta and with or without

spongy tissue beneath the inner woody sclerotesta Endosperm haploid, derived from the fe-

male gametophyte Embryo straight, with 2 cotyledons that are usually united at the tips and a

very long, spirally twisted suspensor; seeds platyspermic; germination cryptocotylar About 90 species, chiefly Australian (27 species) and Indo-Chinese (about 35 species) The genus also occurs in the Malesian region, Japan, and India, extending to Micronesia and Polynesia, Madagascar, and East Africa Plants are commonly understory shrubs in forest, woodland, or savanna habitats Four sections have been recognized (Hill, 1995), although there has been disagreement on subgeneric division (Wang, 1996; de Laubenfels & Adema, 1998), and, in the light of improved understanding of the genus, none of the proposed systems would appear entirely adequate (Hill, 2004) Three clear groups, regarded below sections, oc- cur naturally in Vietnam (Fig 1), and a fourth is represented by one widely cultivated species Vietnam has the greatest diversity at the sectional level and the highest number of species of any country except Australia

T a b l e I

C o n s e r v a t i o n s t a t u s o f V i e t n a m e s e c y c a d s

Cycas species

Reserved Occurrence 1997 IUCN outside Red 1994 Population Vietnam List status size

Present decline

Range

(km)

Habitat reduction

y VU A2c >10,000 high DD/CR 1000-2500 low

?80 50-80 20-50

20-50

20-50 20-50

100

50

<20

<20

140 THE BOTANICAL REVIEW

Key to sections occurring in Vietnam

1 Ovules tomentose Section Asiorientales*

1 Ovules glabrous

2 Microsporangiate sporophylls soft, lacking an apical spine or

with a very slender, tightly appressed apiculus Section Stangerioides

2 Microsporangiate sporophylls hard, with a distinct apical spine

3 Megasporophyll pectinate Section l n d o s i n e n s e s

3 Megasporophyll entire or dentate, not deeply pectinate Section C y c a s

Key to the species in Vietnam

1 Pinnae simple

2 Megasporophyll pectinate

3 Pinnae with margins revolute or strongly recurved C revoluta*

3 Pinnae with margins fiat or moderately recurved, never revolute

4 Microsporangiate cones soB; sarcotesta not fibrous; sclerotesta

with more or less rugose ornamentation

5 Apical spine of megasporophyll lamina dilated, markedly

different from lateral spines

6 Leaves flat

7 Megasporophyll lamina 35-55 x 30-50 mm 15 C s e x s e m i n i f e r a

7 Megasporophyll lamina 65-120 • 60-80 mm 14 C f e r r u g i n e a

6 Leaves keeled 16 C tropophylla

5 Apical spine of megasporophyll lamina not dilated, similar to

lateral spines

8 Microsporophyll with a distinct terminal spine

9 Leaves more than 1 m long, pinnae 14-20 mm wide

10 Leaves to 360 cm long, with 100-160 pinnae; megasporo-

phyll lamina with 6-9 teeth, seeds 5-40 mm long 6 C tanqingii

10 Leaves to 240 cm long, with 80-110 pinnae; megasporo-

phyll lamina with 15-25 teeth, seeds 18-27 mm long 7 C chevalieri

9 Leaves less than 1 m long, pinnae 10-15 mm wide 8 C h o a b i n h e n s i s

8 Microsporophyll lacking a terminal spine

11 Petiolar spines 4-10 mm long

12 Pinnae 10-13 mm wide, narrowed and tapered

at base 4 C b a l a n s a e

12 Pinnae 13-21 mm wide

13 Pinnae abruptly rounded at base; petiole short 10 C d o l i c h o p h y l l a

13 Pinnae tapered at base; petiole long 5 C a c u l e a t a

11 Petiolar spines 1-3 mm long

14.5-10 leaves in crown, leaves with 100-200 pinnae, pinnae 10-14 mm wide 9 C b r a c h y c a n t h a

14 1-5 leaves in crown, pinnae more than 15 mm wide

* This species, native to Japan and China, is widely cultivated throughout Vietnam, but it is neither native nor naturalized It is not discussed any further in this treatment

15 Leaves with more than 100 pinnae; microsporan-

giate cones 25 cm long, 7 cm diam or more 1 C collina

15 Leaves with less than 110 pinnae; microsporan-

giate cones 20 cm long, 6 cm diam or less

16 Teeth on megasporophyll lamina 40-100 mm long 2 C f u g a x

16 Teeth on megasporophyll lamina 15-25 mm long 3 C simplicipinna

4 Microsporangiate cones firm; sarcotesta with a fibrous layer; sclerotesta

18 Microsporangiate cones up to 20 cm long,

5 cm diam.; plants acaulescent; leaves distinctly keeled (opposing pinnae inserted at 90-130 ~ on rachis) 22 C lindstromii

18 Microsporangiate cones 25-60 cm long, 5-30 cm diam.; at least some plants developing an aerial stem; leaves fiat

or openly keeled (opposing pirmae inserted at more than 150 ~ on rachis)

19 Microsporophylls with an attenuate spinose tip 17-40 mm long; micro- sporangiate cones more than 16.5 cm diam 17 C p e c t i n a t a

19 Tips o f microsporophylls not exceeding

16 mm; microsporangiate cones less than 15 cm diam

20 Petiole short (10-20 cm long, 10-20%

o f total leaf length; petiole spinescent for 80-100% of length

21 Pinnae 6-8 mm wide, seedling pinnae 5-7 mm wide 19 C elongata

21 Pinnae 7-10 mm wide, seedling pinnae 7-10 mm wide 20 C p a c h y p o d a

20 Petiole long (20 cm long or longer, 15-50% of total leaf length); petiole unarmed or spinescent for less than 70% o f length

22 Apical spine of microsporophyll less than 6 mm long 18 C clivicola

22 Apical spine of microsporophyll more than 8 mm long 21 C c o n d a o e n s i s

142 THE BOTANICAL REVIEW

2 Megasporophyll not pectinate

1 Pinnae dichotomously divided

23 Lateral spines on megasporophylls distinct; leaves 60-90 cm long;

seeds with fibrous sarcotesta;

spongy layer absent 24 C inermis

23 Lateral spines on megasporophylls indistinct; leaves 150-250 cm long;

seeds lacking a fibrous sarcotesta;

spongy layer present 25 C litoralis

24 Pinnae themselves pinnately divided 13 C multipinnata

24 Pinnae dichotomously divided only

25 Microsporangiate cones more than

6 cm diam., 20 cm long; median microsporophylls rounded 12 C bifida

the Chinese species and ranges from northern Thailand and northeastern Myanmar eastward through Laos, Vietnam, and southern China Fifteen species occur in Vietnam, mostly in the north (Figs 2, 8, 9)

1 CYcAS COLLINA K D Hill, H T Nguyen & Phan K Loc, sp nov

TYPE: Vietnam: Son La: Mai Son, between Hat Lot and Bac Yen, alt 400-900 m, 5 Apr

1996, S L Yang 777 & 1-1 T Nguyen (HOLOTYPE: HN)

Inter species' sectionem Stangerioidem foliis paueis, foliolis late dispositis, strobilis masculis magnis, microsporophyllis apice non spinosis, megasporophyllis reductis spinam apica- lem carentibus distinguitur

Stems 15-80 cm long, 8-13 cm diam., usually subterranean or procumbent, 2-5 leaves

in crown Leaves bright to deep green, moderately glossy, 140-330 cm long, flat (not keeled)

in section (opposing pinnae inserted at 150-180 ~ on rachis), with 11 0-180 pinnae, with orange tomentum shedding as leaf expands, rachis consistently terminated by paired pinnae

Petiole 70-190 cm long (40-55% of total leaD, glabrous, spinescent for 90-100% of length

Basal pinnae not gradually reducing to spines, 200-260 m m long Median pinnae simple, strongly discolorous, 280-450 m m long, 17-23 m m wide, inserted at 80-85 ~ to rachis,

Table II

The Cycas simplicipinna complex

Microsporophyll lamina soft, not dorsiventrally thickened, 12-14 m m long, 7.5-10 m m wide, fertile zone 8-10 m m long, sterile apex 3 4 m m long, deflexed, apical spine absent

Megasporophylls 10-14 cm long, brown-tomentose; ovules 2-4, glabrous; lamina ovate, 60

mm long, 30 mm wide, deeply pectinate, with 10-14 soft spines ca 30 mm long, ca 2 m m wide, apical spine not distinct from lateral spines Seeds ovoid, 25-27 mm long, 18-21 m m wide; sarcotesta yellow, not pruinose; fibrous layer absent; sclerotesta lightly verrucose; spongy layer absent

Distinguishing features: Its few leaves with widely spaced pinnae and large microsporan- giate cones with rounded microsporophylls that lack any apiculus distinguish Cycas eollina

within a group of acaulescent taxa that have reduced megasporophylls lacking a clearly distinct apical spine (Table II) This species was referred to C simplicipinna (below) in the past

Distribution and habitat: Somewhat restricted in distribution, in mountainous regions mostly

in Son La Province in northern Vietnam (Fig 2), above about 500 m elevation, in evergreen or partly deciduous forests or woodlands or bamboo thickets on steep slopes of mountain ridges Substrate varies from red clay soils on limestone to loamy soils on metasediments This species may also be expected to occur in similar terrain in Laos, although adjacent terrain in Laos is generally of lower elevation

A population occurring west of the townlet o f M o c Chau has more numerous leaves, pinnae with slender bases, short to medium petioles, and small seeds and is interpreted as a zone of intergradation with Cycas dolichophylla, which is abundant in lower country to the east (speci- mens cited below)

Conservation status: A widespread species, though not occurring in large or dense popula- tions Although its habitat is continually being reduced, many populations remain, and it is not under any immediate threat of extinction IUCN Red List status VU A2e

Etymology: From the Latin collinus, pertaining to hills, from the occurrence in high ridge country

Selected specimens examined: VIETNAM Son La: Moc Chau, Chieng Hac, Chieng Pan (21 ~

N, 104029'53 " E), alt ca 500 m, 21 Mar 1999, Hill 5060 & Loe (HN, NSW); Yen Chan, Chieng Don, Chieng Dong pass (21007'29" N, 104012'25" E), alt ca 800-900 m, 2l Mar 1999, Hill 5061 & Loc (HN,

144 THE BOTANICAL REVIEW

Fig 2 Distributions o f Cycas aculeata, C balansae, C brachycantha, C chevalieri, C collina,

C diannanensis, C dolichophylla, C fugax, C hoabinhensis, C segmentifida, C simplicipinna, and

C tanqingii

NSW); Thuan Chau, Chieng Pac, Phang pass, 21 km from Son La (21~ " N, 103046'26 " E), alt ca 800-900 m, 22 Mar 1999, Hill 5062 & Loc (HN, NSW); Thuan Chau, Phong Lai (21 ~ N, 103~ E), alt ca 800-900 m, 22 Mar 1999, Hill 5063 & Loc (HN, NSW); Mai Son, between Hat Lot and Bac Yen, alt 400-900 m, Yang 778 & Hi,p, 5 Apr 1996 (HN)

Intergrading population: Cycas collina • Cycas dolichophylla

VIETNAM Son La: Moc Chau, Moc Chau townlet, 14th village (20~ " N, 104035'25 " E), W of Moc Chau, cult in gardens, coll from 3 km to SW and 1 km to N, 21 Mar 1999, Hill 5058, 5059 & Loc

(HN, NSW)

2 CYCAS FUGAX K D Hill, H T Nguyen & Phan K Loc, sp, nov (Fig 3)

TYPE: Vietnam: Phu Tho: Phong Chau, Tram Than, Lam, alt 400-900 m, H T Nguyen

4112 & K D Hill, 13 Jan 2000 (HOLOTYPE: HN; ISOTYPE: NSW)

Inter species sectionem Stangerioidem foliis paucis, foliolis late dispositis, foliolis latis ad bases angustas graduatim contractis, strobilis masculis parvis, microsporophyllis apice spinosis, megarporophyllis reductis spinam apicalem carentibus et spinis lateralibus elongatis distinguitur

Stems acaulescent, flask shaped, wholly subterranean, ca 18 cm long, 15 cm diam, at base, l0 cm diam at apex, larger and branched in some older plants, 1-3 leaves in crown Leaves

bright to deep green, moderately glossy, 280-380 cm long, flat (not keeled) in section (oppos- ing pinnae inserted at 160-180 ~ on rachis), with 80-100 pinnae, with orange tomentum shed- ding as leaf expands, rachis consistently terminated by paired pinnae Petiole 150-220 cm long (50-60% of total leaf), glabrous, spinescent for 90-100% of length Basalpinnae not gradu- ally reducing to spines, 120-300 mm long Median pinnae simple, strongly discolorous, 4 0 0 -

500 mm long, 18-27 mm wide, inserted at 70-85 ~ to rachis, decurrent for 5-10 mm, narrowed

to 2-3 mm at base (to 10-15% of maximum width), 30-40 m m apart on rachis, section flat, margins flat or undulate; apex softly acuminate, not spinescent; midrib raised above, flat below Cataphylls narrowly triangular, soft, pilose, 30-50 m m long Microsporangiate cones

fusiform, cream, 10-12 cm long, 2.5-4 cm diam Microsporophyll lamina soft, not dorsiven- trally thickened, 12-14 m m long, 7.5-10 mm wide, fertile zone 8-10 m m long, sterile apex 3-6 mm long, deflexed, apical spine slender, closely appressed, 2 - 4 m m long Megasporo- phylls 20-25 cm long, brown-tomentose; ovules 2-4, glabrous; lamina ovate, 110-130 mm long, 35-40 mm wide, deeply pectinate, with 10-14 soft spines 50-90 mm long, 3 m m wide, apical spine not distinct from lateral spines Seeds ovoid, 25-27 mm long, 18-21 m m wide; sarcotesta yellow, not pruinose; fibrous layer absent; sclerotesta verrucose; spongy layer ab- sent

Distinguishing features: Its few, very long leaves with few, widely spaced pinnae with very narrow, tapering bases, small microsporangiate cones with microsporophylls that possess a distinct apiculus, and elongated teeth on its megasporophylls distinguish Cycasfugax within a group of acaulescent taxa that have megasporophylls lacking a clearly distinct apical spine (Table II) This species was referred to C simplicipinna in the past

Distribution and habitat." Known only from Phu Tho Province in northern Vietnam (Fig 2),

at about 200 m elevation Originally growing in closed evergreen forests on low hills of or- ange-brown alluvial loam Almost all of this forest on this substrate has been cleared for tea, eucalypt, and Acacia plantations

Conservation status: Apparently a very rare and restricted species, known only from a se- verely threatened habitat This species must be regarded as critically endangered and urgently

in need of both close study to evaluate the conservation status and protective measures IUCN Red List status DD/CR?

Etymology: From the Latin fugax, fleeting or ephemeral, referring to the near extinction of this species before it was recognized as a botanical entity

Selected specimens examined: VIETNAM Phu Tho: Phong Chau, Tram Than (21o39'27 " N, 105~ E), cult in garden, said to be coll nearby, 26 Mar 1999, Hill 5070, 5071, 5072 & Loc (HN,

NSW); cult in Phu Tho, 31 Mar 1996, Yang 775 & HMp (HN)

Fig 3 Cycasfugax a Habit b Part o f leaf c Megasporophyll with ovules and stipe (a, b f r o m HiOp 4111; c from Hi~p 4112) Bar: a = 20 cm; b = 5 cm; c = 1 cm

3 CYcAS S1MPLICIPINNA (Smitinand) K D Hill, Proc Third Int Conf Cycad Biol.: 150 1995

Cycas micholitzii vat simplicipinna Smitinand, Nat Hist Bull Siam Soc 24: 164, figs 2-3, 4f 1971

TYPE: Thailand: Chiang Mai Province, Doi Suthep, alt.ll00 m, 19 Jul 1958, Smitinand

4757 (LECTOTYPE: BKF fide Hill, 1995)

Cycas immersa non Craib, sensu Suvatabandhu (1961)

Cycas tonkinensis, in part, sensu de Laubenfels and Adema (1998)

Literature." Smitinand (1972)

Illustrations: Smitinand (1971); Wang (1996)

Stems acanlescent, 8-14 cm diam at narrowest point, subterranean or procumbent, 2-5

leaves in crown Leaves bright to deep green, highly glossy, 90-250 cm long, flat (not keeled)

in section (opposing pinnae inserted at 160-180 ~ on rachis), with 35-90 pinnae, with orange

tomentum shedding as leaf expands; rachis consistently terminated by paired pinnae Petiole 35-140 cm long (40-60% of total leaf), glabrous, spinescent for 60-100% of length Basal

pinnae not gradually reducing to spines, 120-300 mm long Median pinnae simple, strongly

discolorous, 200-600 mm long, 14-20 mm wide, inserted at 50-65 ~ to rachis, decurrent for 5 - l0 mm, narrowed to 2.5-4 mm at base (to 15-30% of maximum width), 20-40 mm apart on rachis; section flat; margins flat or undulate; apex softly acuminate, not spinescent; midrib

raised above, flat below Cataphylls narrowly triangular, soft, pilose, 40-50 mm long, articu- lated Microsporangiate cones fusiform, cream, 15-21 cm long, 2.2-4 cm diam Micro~poro-

phyll lamina soft, not dorsiventrally thickened, 12-14 mm long, 7.5-10 mm wide, fertile zone

8-10 mm long, sterile apex 3-6 mm long, raised, apical spine absent Megasporophylls 7-12

cm long, brown-tomentose; ovules 2, glabrous; lamina ovate, 45-55 mm long, 18-35 mm wide, deeply pectinate, with 10-14 soft spines 15-25 mm long, 1.5-2 mm wide, apical spine

not distinct from lateral spines Seeds ovoid, 25-27 mm long, 18-21 mm wide; sarcotesta

yellow, not pruinose; fibrous layer absent; sclerotesta verrucose; spongy layer absent

Distinguishing features: Its almost totally subterranean habit with a very sparse crown of large, erect leaves with few, broad, and well-spaced pinnae, small microsporangiate cones, small megasporophylls with short spines on the apical lamina, and small seeds distinguish this species within the group of acaulescent species occurring in the Indochina region (Section

Stangerioides)

Distribution and habitat: Known from westem Quang Tri Province only in Vietnam (Fig 2) Widely distributed in the mountains in northem Thailand, only above about 600 m elevation, usually in wetter and more sheltered sites in deep shade in tall, closed evergreen forests This species also occurs in northern Myanmar and Laos Individuals are usually scattered and spo- radic in occurrence, and dense stands are uncommon

Conservation status: A very widespread species, though not occurring in large or dense populations Although its habitat is continually being reduced, many populations remain across

a wide range (from north central Vietnam to northwestern Thailand and nearby Myanmar), and

it is not under any immediate threat of extinction

Selected specimens examined: VIETNAM Quang Tri: Lao Bao, cult., coll nearby, 21 Jan 2000,

Hi~p 4130 & Hill (HN, NSW)

THAILAND Chiang Mai: Doi Suthep, Kerr 3206, 17 May 1914 (BM, K); Doi Inthanon, Kerr 5347,

4 May 1921 (BM, K); Chiang Mai, Kerr 5645, 13 Aug 1921 (BM, K); Phong Pho, 12 km N of Doi Chiang Dao, Larsen, Santisuk & Warncke 2859, 30 Jul 1968 (BKF); Inthanon National Park, Phengklai et al

6749 (BKF) Loei: Khao Kating, Phu Kradung, Abbe, Abbe & Smitinand 9473, 13 Jan 1960 (BKF, L)

148 THE BOTANICAL REVIEW

Mac Hang Song: Nam Tok Phasua, N of Mac Hang Song, Hill 4637, 26 Apr 1994 (NSW) Phrae: Mac

Sai, Winit 1686, 28 Mar 1926 (K)

LAOS Louang Prabang, Pottier 71A (P); Phouiou Yhouan, Pottier 57B (P); Nam Minh, Pedrono 87 (P)

MYANMAR Reported by plant collectors in northern Thailand; no voucher

4 CYCAS BALANSAE Warb., Monsunia 1:179 1900 Cycas siamensis subsp, balansae (Warb.)

Schuster, Pflanzenr 99: 81 1932

LECTOTYPE (here designated): Tonkin (Vietnam), Hanoi, Mar 1889, B Balansa 4084 (LEC-

TOTYPE, see below: P; ISOLECTOYPES: G-DC, C~ K)

Cycas shiwandashanica H T Chang & Y C Zhong, Chinese Bull Bat 12: 12 1995 TYPE:

Guangxi: Nasuo, Fangchenggang City, in broad-leaved forest, Y C Zhong 88015, 30

Jul 1990 (HOLOTYPE: GXF; ISOTYPES: PE, SYS)

Cycaspalmatifida H T Chang, Y Y Huang & Y C Zhong, Acta Sci Nat Univ Sunyatseni

37: 7 1998 TYPE: China: Guangxi: cult in Nanning Arboretum, H X Zheng & Y Y

Huang 98002, 19 Apr 1998 (HOLOTYPE: SYS)

Cycas tonldnensis, in part, sensu de Laubenfels and Adema (1998)

Literature: Chen and Stevenson (1999)

Illustrations: Cheng et al (1975), as Cycas siamensis; Wang (1996), and as Cycas shiwan- dashanica

Stems acaulescent, 12-20 cm diam at narrowest point, 4-9 leaves in crown Leaves deep

green, highly glossy to semigiossy, 120-260 cm long, slightly keeled to fiat in section (oppos- ing pinnae inserted at 160-180 ~ on rachis), with 90-160 pinnae, with dark brown tomentum shedding as leaf expands or persistent on petiole, rachis consistently terminated by paired

pinnae Petiole 40-160 cm long (30-40% of total leaf), pubescent with dark purple-brown tomentum, spinescent for 100% of length Basalpinnae not gradually reducing to spines, 90-

210 mm long Median pinnae simple, strongly discolorous, 220-300 mm long, 10-15 mm

wide, inserted at 75-85 ~ to rachis, decurrent for 5-8 mm, narrowed to 3-4 mm at base (to 25- 35% of maximum width), 11-21 mm apart on rachis, section fiat; margins fiat or slightly re-

curved, apex softly acuminate; not spinescent, midrib raised above, fiat below Cataphylls narrowly triangular, soft, pilose, 60-70 mm long Microsporangiate cones fusiform, yellow, 20-25 cm long, 4-7 cm diam Mierosporophyll lamina soft, not dorsiventrally thickened, 16-

30 mm long, 11-14 mm wide, fertile zone 14-28 mm long, sterile apex 2-4 mm long, level,

apical spine absent Megasporophylls 8-12 cm long; brown-tomentose; ovules 2-4, glabrous;

lamina ovate, 4 0 ~ 0 mm long, 30-55 mm wide, deeply pectinate, with 14-24 soft spines 25-

40 mm long, 2-3 mm wide, apical spine not distinct from lateral spines Seeds ovoid, 25-27

mm long, 20 mm wide, sarcotesta yellow, not pruinose, 2 mm thick; fibrous layer absent; sclerotesta lightly verrucose; spongy layer absent

Typification: Described by the German botanist Otto Warburg in 1900 A single collection

was cited as "Im Herbarium Barbey finde ich van Balansa sub Nr 4084 gesammelte s162 Zapfen aus Tongking, nahe Hanoi aus einem Tempelhof stammend." Warburg types were mostly held

by B, and Schuster (1932) cited a specimen probably from B that would probably have been the

type: "Tongking: Village du papier bei Hanoi, im Hof einer Pagode (B Balansa IE 1889,

n 4084)." This specimen was evidently destroyed in World War II The specimens in G, K, and

P were not annotated by Warburg or Schuster and may not have been seen by either Most of these specimens are of microsporangiate cone material only, although the material held in P comprises two sheets, one microsporangiate cone portion and one leaf portion The microspo-

rangiate cone sheet is annotated "B Balansa- Pl du Tonkin - 1885-1889/Nr 4084/Dioique

Frondes de deux metres de hauteur/Tongking: Village du papier prks de Hanoi, dans la/cour d'une pagode/Avril 1889" [Dioecious Fronds 2 m high Paper village near Hanoi, in the gar-

den of a pagoda] The two sheets held in P are here designated the lectotype

Distinguishing features: This species is one of the complex of closely related, mostly acaules-

cent taxa that is distributed through northern Vietnam, Laos, northern Thailand, and Yunnan

and Guangxi in southern China (Section Stangerioides) It is distinguished by its few long

leaves with long petioles bearing long, slender spines and its deep purple-brown tomentum that

is often persistent Microsporangiate cones are intermediate in size, with rounded microsporo- phylls that lack any apiculus Megasporophylls are reduced, with a few long and slender divi- sions on the lamina Seeds are small

Distribution and habitat: Locally frequent though not in dense stands, in more sheltered

sites in deep shade in tall, closed evergreen forests, in the region northwest and northeast of Hanoi (Lang Son, Vinh Phuc, Thai Nguyen, and Quang Ninh) and extending into the Shiwandashan (mountains) in coastal southeastern Guangxi Province of China (Fig 2) On loamy soils over schists or granites

Conservation status: Not considered to be at risk IUCN Red List status LRnt

Selected specimens examined: VIETNAM Hal Phong: jardins a Hai Phong, 1885, Balansa 563 (P)

Ha Nam: Ke So, forte ex montibus Kien Khe, 25 May 1889, Bon 4146 (P) Lang Son: Dinh Lap, Dinh Lap townlet (21o32'25" N, 107o06'32" E), 12 Mar 1999, Hill 5026, Loc & Dzu (HN, NSW); Dinh Lap, Bac Lang, Ban Ha, 27 Mar 1996, Yang & Hi~p 763 (HN); Phu Son, Bac Son, Na Danh, 27 Mar 1996,

Yang & Hi~p 765 (HN) Quang Ninh: Hoanh Bo, Tan Dan, Hang Tran (21~ N, 106o52'50 " E), 11

Mar 1999, Hill 5022, 5023, Loc & Dzu (I-IN, NSW); Tien Yen, Dien Xa, Na Tru (21 ~ N, 107 ~ 17'32"

E), 12 Mar 1999, Hill 5025, Loc & Dzu (I-IN, NSW); Cam Pha, 26 Mar 1996, Yang & Hi~p 758 (HN); Quang Nghia, Quang Ha, 27 Mar 1996, Yang & Hi~p 761 (HN); Hai Lang, Tien Yen, 25 Mar 1996, Yang

& Hi~p 767 (HN) Thai Nguyen: Dai Tu, Ky Phu, Xom Gio, 19 Jan 2000, Hi~p 4117 & Hill (HN, NSW)

Tuyen Quang: Son Duong, Son Nam, cult in restaurant, coll from NW side of Tam Dao range, Tam Dao,

Dai Dinh, Den Thong, 17 Mar 1999, Hill 5048 & Loc (HN, NSW)

CHINA Guangxi: Cult on grounds of Nanning Forestry Research Center, Nanning (type plant of

Cycaspalmatifida), coll from Fangcheng County, Chen, Zhong & Hill 01, 7 Nov 1998 (NSW, PE); cult

in Ping Mu village, Na Suo town, Fangcheng County, Guangxi Province, coll from Fang Chen Shang Yue

reserve (21045'34 " N, 108005'33" E), alt 240 m, Chen, Zhong & Hill 28, 19 Nov 1998 (NSW, PE)

5 CYCAS ACULEATA K D Hill & H T Nguyen, sp nov

TYPE: Vietnam: Da Nang: Hai Van pass, lower on S side, H T Nguyen 4156 & K D Hill,

23 Jan 2000 (HOLOTYPE: HN; ISOTYPE: NSW)

A Cycade balansae foliis numerosioribus, petiolis longioribus, foliolis longioribus latiori-

busque parum carinatis basi angustioribus, cataphyllis longioribus differt

Stems acaulescent, 15-18 cm diam at narrowest point, 6-23 leaves in crown Leaves deep

green, highly glossy or semiglossy, 180-250 cm long, slightly keeled (opposing pinnae in- serted at 130-170 ~ on rachis), with 100-150 pinnae, with orange tomentum shedding as leaf

expands; rachis consistently terminated by paired pinnae Petiole 60-110 cm long (35-50% of total leaf), glabrous or pubescent, spinescent for 100% of length Basal pinnae not gradually reducing to spines, 260-380 mm long Median pinnae simple, strongly discolorous, 350-520

mm long, 13-19 mm wide, inserted at 45-60 ~ to rachis, decurrent for 4-6 ram, narrowed to 2 -

3 mm at base (to 10-20% of maximum width), 15-28 mm apart on rachis; section slightly keeled; margins flat; apex softly acuminate, not spinescent; midrib raised above, flat to raised

below Cataphylls narrowly triangular, soft, pilose, 80-100 mm long, persistent Microsporan-

giate cones narrowly ovoid or fusiform, 15-20 cm long, 4 6 cm diam Microsporophyll lamina

150 THE BOTANICAL REVIEW

soft, not dorsiventrally thickened, 22-25 mm long, 12-14 mm wide, fertile zone 20-22 mm long, sterile apex 2-3 mm long, level, apical spine absent Megasporophylls and seeds not

seen

Distinguishing features: This species is one of the complex of closely related, mostly acaules-

cent taxa that is distributed through northern Vietnam, Laos, northern Thailand, and Yunnan and Guangxi in southern China (Section Stangerioides) It is distinguished by its few, long

leaves with long petioles bearing long, slender spines and its light orange-brown tomentum Microsporangiate cones are small, with rounded microsporophylls that lack any apiculus It is most similar to Cycas balansae, differing in its more numerous leaves with relatively longer

petioles, light orange-brown tomentum, longer and wider, slightly keeled pinnae that are more narrowed at the base, and longer cataphylls

Distribution and habitat: Known at present from a single site on the southern slopes of the

range at Hal Van pass, in dense bamboo, shrub, and grass regrowth after forest clearing (Fig 2) Forests in the vicinity were severely affected by herbicide spraying during the north-south war in the early 1970s It is locally frequent on loamy soils over granite on steep slopes, but the extent of the occurrence is unknown

Conservation status: Although very poorly known to date, it is likely that this species is

more widespread in the surrounding hills, IUCN Red List status I)D, possibly VU

Etymology: From the Latin aculeatus, prickly, in reference to the prominent spines on the

petiole

Selected specimens examined: VIETNAM Cult: Cau Hai, in garden in village, coll from Hai Van pass, HiOp 4133 & Hill, 22 Jan 2000 (I-iN, NSW)

6 CVCAS TANQINGII D Yue Wang, Cycads of China: 134 1996 (Fig 4)

TYPE: China: Yunnan: Luchun County, D Z Wang 5538 (HOLOTYPE: SZG; ISOTYPE:

NF n.v.)

Illustrations: Wang (1996)

Stems arborescent or acanlescent, to 2 m tall, 25-30 cm diam at narrowest point, 4-7 leaves

in crown Leaves deep green, highly glossy, 190-360 cm long, flat (not keeled) in section

(opposing pinnae inserted at 170-180 ~ on rachis), with 100-160 leaflets, with orange tomen- turn shedding as leaf expands; rachis consistently terminated by paired leaflets Petiole 70-190

cm long (40-50% of total leaf), petiole glabrous, spinescent for 90-100% of length Basal leaflets not gradually reducing to spines Median leaflets simple, strongly discolorous, 300-

450 mm long, 15-22 mm wide, narrowed to 5-6 mm at base (to 20-30% of maximum width), inserted at 65-85 ~ to rachis, 15-27 mm apart on rachis; section fiat; margins slightly recurved; apex aristate, not spinescent; midrib raised above, raised below Cataphylls narrowly triangu-

lar, soft, pilose to densely floccose, persistent, 50-80 mm long Microsporangiate cones fusi-

form, yellow to orange, 40 cm long, 5-8 cm diam Microsporophyll lamina soft, not dorsiventrally thickened, 25-30 mm long, 10-13 mm wide, fertile zone 22-28 mm long, sterile apex 2-3 mm long, level to raised, apical spine slender, appressed, sharply upturned, 1.5-2 mm long Me- gasporophylls 10-12 cm long, brown-tomentose; ovules 2, glabrous; lamina orbicular, 50-55

mm long, 50-65 mm wide, deeply pectinate, with 6-9 soft spines 15-40 mm long, 1-3 mm wide, apical spine not distinct from lateral spines, 20-45 mm long, 7-30 mm wide at base

Seeds subglobose to ovoid, 35-40 mm long, 30-35 mm wide; sarcotesta yellow, not pruinose,

2 mm thick; fibrous layer absent; sclerotesta verrucose; spongy layer absent

Distinguishing features: Its robust habit with a stout, aerial trunk, large microsporan-

giate cones, and seeds distinguish this species within Section Stangerioides Cycas tanqingii

Fig 4 Cycas chevalieri, a Habit b Part o f leaf c Section o f pinna, d Megasporophyll with stipe (from Hill 5005) Bar: a = 50 cm; b = 8 cm; c = 1 cm; d = 6 cm

appears to be nearest to C dolichophylla, differing in its longer and m o r e w i d e l y spaced pinnae that are n o t b r o a d - b a s e d and r o u n d e d at the base and its longer petioles

Distribution and habitat: R e m o t e and m o u n t a i n o u s country in southeastern Yunnan Prov- ince, China, possibly also across the border in Vietnam, in closed evergreen forest

Conservation status: U n k n o w n

152 THE BOTANICAL REVIEW

Selected specimens examined: VIETNAM Lai Chau: reported by forestry workers from Luchun County, China, to occur on Vietnamese side of the Hejiang [river], no voucher

CHINA Yunnan: Luchun County, Xaio Hejiang District, Ping He, Hong 355, 356, 357, Chen, Hill & Stevenson, 9 Jul 2000 (YUN, NSW, NY, PE)

7 CYcAS CHEVALIERI Leandri, in Lecomte, F1 Indo-Chine 5(10): 1092 1931

LECTOVYeE (here designated): Vietnam Nghe An Prov., Nghia Dan, Nghia Hung (Tram

Cycas tonkinensis, in part, sensu de Laubenfels and Adema (1998)

Stems arborescent or acaulescent, developing an elongate, often decumbent, stem with age,

to 1.2 m tall, 8-18 cm diam at narrowest point, 4-15 leaves in crown Leaves deep green, highly glossy, 130-240 cm long, slightly keeled to flat in section (opposing pinnae inserted at 150-180 ~ on rachis), with 80.110 pinnae, with orange or brown tomentum shedding as leaf expands, rachis consistently terminated by paired pinnae Petiole 70-140 cm long (45-60% of total leaf), glabrous, unarmed or spinescent for up to 100% of length Basalpinnae not gradu- ally reducing to spines, 170-240 mm long Median pinnae simple, strongly discolorous, 250-

420 mm long, 14.20 mm wide, inserted at 50-80 ~ to rachis, decurrent for 2-6 ram, narrowed

to 2.5-4 mm at base (to 15-30% of maximum width), 15-21 mm apart on rachis; section flat, margins flat or undulate, apex softly acuminate, not spinescent; midrib raised above, raised below Cataphylls narrowly triangular, soft, pilose, 50 70 mm long Microsporangiate cones

fusiform, brown or cream, 15-25 cm long, 4 7 cm diam Microsporophyll lamina soft, not dorsiventrally thickened, 14-17 mm long, 7-10 mm wide, sterile apex raised, apical spine absent Megasporophylls 9-13 cm long, brown-tomentose; ovules 2-4, glabrous; lamina or- bicular, 35-55 mm long, 25-50 mm wide, deeply pectinate, with 15-25 soft lateral spines 2 0 -

35 mm long; apical spine sometimes distinct from lateral spines, 25-40 mm long, 3-8 mm wide

at base Seeds ovoid, 18-27 mm long, 15-25 mm wide; sarcotesta yellow, not pruinose, 1-2

mm thick; fibrous layer absent; sclerotesta verrucose; spongy layer absent

Typification: Two collections were cited, as follows: "Tonkin occidental: (Chevalier) - Nord-Annam: prov de NghO-an (Vinh), dOldgation de Nghia-h~ng ?t Tram-lui (Chevalier)."

Only the second specimen (Chevalier 32612) appears to remain, and it is here designated the lectotype

Historical notes: Published by the French botanist J D Leandri in 1931, this name was ignored by Ho in his general enumerations of Vietnamese plants (Ho & Duong 1960; Ho 1991) Cycas chevalieri was placed in the synonymy of the related C balansae by Hifp & Vidal (1996) but is now recognized as a distinct species more closely allied to C hoabinhensis

than to C balansae This species was largely unknown except for the type collections until re- collected in 1998 The original type locality was by this time cleared for cultivation and had been previously searched for C chevalieri, in vain The recent discovery of large numbers of plants was made some 120 km to the south, in relatively undisturbed forest in the foothills of the Annam Highlands Subsequent field studies have extended the range south to Khe Sanh in Quang Tri and show this to be a widespread and abundant species

Distinguishing features: Within a complex of closely related, mostly acaulescent taxa (Sec- tion Stangerioides), this species is distinguished by its medium stature, broad pinnae, long petioles relative to total leaf length, erect petioles with short spines that are not usually contin- ued onto the swollen leaf base, reflexed leaf blade, small megasporophylls lacking a clearly distinct apical spine, and small microsporangiate cones with a slender apical spine on its mi- crosporophyll Older plants develop a slender, often decumbent, aerial trunk

D&tribution and habitat: Locally abundant in tall, closed evergreen forest on sandy loams over schists and granites in the region inland from Vinh and Ha Tinh and south to Khe Sanh, in mountain foothills in Nghe An, Ha Yinh, Quang Binh and Quang Tri Provinces (Fig 2) This species often grows in boulder beds along riverbanks, where it may form large, multiheaded clusters

Conservation status: Not considered to be at risk Very large populations occur in well- preserved forest IUCN Red List status LRnt

Selected specimens examined: VIETNAM Ha Tinh: Huong Son, Son Kim, Rao An (18~ " N, 105~ " E), 13 May 1998, Hill 5004, 5005, 5006 & Loe (NSW, HN, K, NY, PE, BKF, L) Nghe An: Dien Chau, Dien Lam, 29 Oct 1994, HiOp & Yang 2019 (HN); Yang & HiOp SLY530 (HN) Quang Tri: Dak Rong, Cu Poho, Rao Quan River, 21 Jan 2000, Hi~p 4126 & Hill (HN, NSW)

8 CYCAS HOABINHENSIS Phan K Loc & H T Nguyen, sp nov (Fig 5)

TYPE: Vietnam: Hoa Binh: Lac Thuy, Chi Ne, Jul 1966, Phan K Loc P3194a (HOLO- TYPE: HNU; ISOTYPE: HN, NSW)

Inter species sectionem Stangerioidem statura parva, foliis paucis brevibus, foliolis paucis latis, strobilis masculis parvis, microsporophyllis apiee spiniferis, megasporophyllis reductis spinam apicalem carentibus et spinis lateralibus reductis distinguitur Stems arborescent or acaulescent, to 0.6 m tall, 5-8 cm diana, at narrowest point, 2-10 leaves in crown Leaves bright green, highly glossy, 50-130 cm long, flat (not keeled) in sec- tion (opposing pinnae inserted at 170-180 ~ on rachis), with 40-100 pinnae, with white tomen- tum shedding as leaf expands, rachis consistently terminated by paired pinnae Petiole 25-60

cm long (40-60% of total leaf), glabrous, spinescent for 100% of length, basal pinnae not gradually reducing to spines, pinnae 150-250 mm long Median pinnae simple, strongly discolorous, 200-280 mm long, 11-21 mm wide, inserted at 60-80 ~ to rachis, decurrent for 2 -

4 ram, narrowed to 2.5-5 mm at base (to 15-30% of maximum width), 15-20 mm apart on rachis, section flat, margins flat or undulate, apex softly acuminate, not spinescent; midrib raised above, raised below Cataphylls narrowly triangular, soft, pilose, 50-70 mm long Mi- crosporangiate cones narrowly ovoid or fusiform, yellow, 10-12 cm long, 5-6 cm diam Mi- crosporophyll lamina soft, not dorsiventrally thickened, 22 mm long, 10 mm wide; fertile zone

20 mm long, sterile apex 2 mm long, raised, apical spine distinct or rudimentary, appressed, sharply upturned, 4-10 mm long Megasporophylls 7 cm long, brown-tomentose; ovules 2 4 , glabrous; lamina orbicular, 30 mm long, 20 mm wide, deeply pectinate, with ca 10 soft spines

ca 20 mm long, ca 2.5 mm wide, apical spine not distinct from lateral spines Sarcotesta yellow, not pruinose; fibrous layer absent; sclerotesta verrucose; spongy layer absent

Historical notes: Though an abundant species occurring naturally near the large city of Hanoi and very popular as a horticultural subject in that city in recent years, this was not recognized as a distinct species until 1996-1998, when field studies permitted the true com- plexity of the taxonomy of the northern Vietnamese cycads to become clearer

Distinguishing features: Within a complex of closely related, mostly acaulescent taxa (Sec- tion Stangerioides), this species is distinguished by its very small stature, small megasporo- phylls lacking a clearly distinct apical spine, and slender apical spine on the microsporophyll

It is nearest to Cycas chevalieri and C brachycantha, both of which share its small megasporo- phyll but are otherwise larger in stature Older plants develop a short, very slender, often twisted

or decumbent, aerial think

Distribution and habitat: Locally abundant, in somewhat sheltered sites on steep limestone outcrops, usually within the canopy of closed evergreen forest on ridge crests in the region

Fig 5 Cycas hoabinhensis, a Leaf b Part o f leaf e Habit and mierosporangiate cone d, e, L Microsporophyll g Habit and megasporophylls, h Megasporophyll w i t h seeds and stipe ( a - f from Binh s.n.; g, h from Loc 3194A) Bar: a, c, g = 8 cm; b = 4 cm; d, e, f = 1 cm; h = 2 cm

south of Hanoi (Fig 2) The habitat is the same as that of the closely related Cycas brachycantha

from north of Hanoi

Conservation status: This species has been extensively exploited for the ornamental plant trade in Hanoi, severely depleting many of the more accessible populations Although large populations remain in relatively inaccessible areas, the extensive depletion to date (and con- tinuing) is cause for concern, and this species must be regarded as threatened IUCN Red List status EN A2e

Etymology: From the occurrence in Hoa Binh Province, northern Vietnam, with the Latin termination -ensis, place of origin

Selected specimens examined: V1ETNAM Ha Nam: Kim Bang, Ba Sao, Mar 1996, Binh s.n (HN); cult in Dien Birth, Gia Lam District, Hanoi, plant coll from Than Liem District (ca 20 ~ 27' N, 106o02 ' E), 11 May 1998, Hill 5003 & Loe (NSW, I-IN, K) Ha Tay: Chua Huong, 21 Mar 1996, Yang & Hi~p SLY757 (HN) Hoa Binh: Luong Son, 22 Oct 1994, Yang & Hi~p SLY519 (HN); Lac Thuy, Chi Ne, 24 Oct

1994, Yang & HiOp SLY425 (HN) Ninh Binh: Cuc Phuong, 15 Jun 1995, Hi~p 2056 (HN); Nho Quan, Cuc Phuong Cuc Phuong National Park, ridge crest near gate (20~ N, 105~ '48" E), 18 Mar 1999,

Hill 5050 & Loc (HN, NSW)

9 CYCAS BRACHYCANTHA K D Hill, H T Nguyen & Phan K Loc, sp nov (Fig, 6)

TYPE: Vietnam: Bac Can: Ba Be, Hin Dan Mountain, 14 T Nguyen 4119 & K D Hill, 17 Jan 2000 (HOLOTYPE: HN; ISOTYPE: NSW)

Inter species sectionem Stangerioidem statura modica, foliis paucis, strobilis masculis omni-

no parvis, pedunculo longo, microsporophyllis apice non spinosis, megasporophytlis reductis spinam apicalem carentibus et spinis lateralibus elongatis distinguitur Stems 0-1 m tall, 9-12 cm diam., 5-10 leaves in crown Leaves deep green, highly glossy, 140-250 cm long, slightly keeled to flat (not keeled) in section (opposing pinnae inserted at 160-180 ~ on rachis), with 100-210 pinnae, with white tomentum shedding as leaf expands, rachis consistently terminated by paired pinnae Petiole 50-90 cm long (35-45% of total leaf), glabrous, spinescent for 90-100% of length Basal pinnae not gradually reducing to spines, 150-200 mm long Median pinnae simple, strongly discolorous, 200-250 mm long, 10-14

mm wide, inserted at 70-85 ~ to rachis, decurrent for 6-8 ram, narrowed to 2.5-4 mm at base (to 20-30% of maximum width), 10-21 mm apart on rachis, section flat, margins undulate; apex softly acuminate, not spinescent; midrib raised above, flat below Cataphylls narrowly triangu- lar, pungent, pilose, 50-80 mm long, articulated Microsporangiate cones fusiform, yellow, 12-14 cm long, 3-4 cm diam Microsporophyll lamina soft, not dorsiventrally thickened, ster- ile apex level, apical spine absent Megasporophylls 8-12 cm long, hrown-tomentose; ovules 2-4, glabrous; lamina ovate, 25-40 mm long, 15-25 mm wide, deeply pectinate, with 14-22 soft spines 15-25 mm long, ca 2.5 mm wide, apical spine not distinct from lateral spines

Seeds ovoid, 25-27 mm long, 20 mm wide; sarcotesta yellow; fibrous layer absent; sclerotesta verrucose; spongy layer absent

Historical notes: Cycas brachycantha was first discovered and recognized as a distinct species only in the late 1990s

Distribution and habitat: Known at present from a limited region in Bac Can Province (Fig 2) Locally frequent, though not in dense stands, on the crests of outcropping limestone ridges within closed evergreen forest canopy, growing in clefts and crevices in bare rock with little or

no soil

Fig 6 Cycas brachycantha, a Habit b Part o f leaf c M e g a s p o r o p h y l l with stipe ( f r o m Hi~p 4119)

Distingu&hingfeatures: Its medium stature, very small microsporangiate cones on long

peduncles with rounded microsporophylls that lack any apiculus, and long petioles with short spines distinguish this species It is also part of the complex of closely related, more or less acaulescent taxa with reduced megasporophylls lacking a clearly distinct apical spine that is distributed through northern Vietnam, Laos, northern Thailand, and Yunnan and Guangxi in southern China Older plants develop a slender, often decumbent, aerial trunk Within this complex its reduced megasporophylls suggest that Cyeas brachycantha is nearest to C hoa- binhensis and C chevalieri

Conservation status: Well represented within Ba Be National Park and not considered to be

at risk IUCN Red List status LRnt

Etymology: From the Greek brachys, short, and aeanthos, spine, referring to the character-

istically short petiolar spines of this species

Selected specimens examined: VIETNAM Bac Can: Cho Don, Nam Mau, hills behind village, 15 Mar 1999, Hill 5033 5034 & Lor (HN, NSW); cult in village, coll nearby, 15 Mar 1999, Hill 5035 & Loe (HN, NSW)

10 CYCAS DOLICHOPHYLLA K D Hill, H T Nguyen & Phan K Loc, sp nov (Fig 7)

TYPE: Vietnam: Tuyen Quang: Na Hang, Pu La Mountain, 2 Nov 1996, H T Nguyen 2124

(HOLOTYPE: HN)

Inter species sectionem Stangerioidem statura magna, trunco aerio robusto, foliis multo longioribus, petiolo brevi, foliolis latis confertis brevioribus basi abrupte contract&, strobilis masculis magnis, microsporophyllis apice non spinosis, megasporophyllis reductis spinam apicalem carentibus et spinis lateralibus elongatis distinguitur Stems arborescent, to 1.5 m tall, 18-30 cm diam at narrowest point 8-40 leaves in crown Leaves bright green to deep green, highly glossy, 200-450 cm long, flat (not keeled) in section

(opposing pinnae inserted at 180 ~ on rachis), with 150-270 pinnae, with orange tomentum shedding as leaf expands; rachis consistently terminated by paired pinnae Petiole 40-110 cm

long (20-35% of total leaf), glabrous, spinescent for 90-100% of length Basal pinnae not

gradually reducing to spines, 90-240 mm long Median pinnae simple, strongly discolorous,

190-420 mm long, 14-25 mm wide, inserted at 60-85 ~ to rachis, decurrent for 5-8 ram, nar- rowed to 34i mm at base (to 20-35% of maximum width), distinctively rounded at base, 16-30

mm apart on rachis; section flat; margins undulate; apex softly acuminate, not spinescent; midrib raised above, fiat below Cataphylls narrowly triangular, soft, pilose, 80-120 mm long Microsporangiate cones narrowly ovoid or fusiform, yellow, 35-58 cm long, 8-10 cm diam Microsporophyll lamina soft, not dorsiventrally thickened, 30-36 mm long, 9-13 mm wide,

fertile zone 27-34 mm long, sterile apex 2-4 mm long, level, apical spine rudimentary or absent, sharply upturned, 0-3 mm long Megasporophylls 15-26 cm long, brown-tomentose;

ovules 2-4, glabrous; lamina orbicular, 60-120 mm long, 50-100 mm wide, deeply pectinate, with 16-26 soft spines 40-50 mm long, 2-3 mm wide, apical spine not distinct from lateral spines Seeds ovoid or flattened-ovoid or oblong, 40-64 mm long, 33-36 mm wide; sarcotesta

yellow, not pruinose, 2-4 mm thick; fibrous layer absent; sclerotesta verrucose; spongy layer absent

Historical notes: Though the most widespread and abundant cycad in northern Vietnam, Cycas dolichophylla was recognized as a distinct species only in the late 1990s

Distinguishing features: Its robust, though usually short, aerial trunk, longer and more nu-

merous leaves with more numerous pinnae that are short, broad, and distinctively rounded at

Fig 7 Cycas dolichophylla, a Habit b Leaf e Part o f leaf d Megasporophyll with stipe (a from Thanh Hoa, Lang Chanh, Dong Luc; b ~ l from Hi~p 2124) Bar: a = 60 cm; b = 24 cm; c = 8 cm; d = 4 cm

the base, long, slender petiolar spines, and larger microsporangiate cones with rounded mi- crosporophylls that lack any apiculus distinguish this species Megasporophylls are similar to

those of Cycas balansae but larger and more robust Cycas dolichophylla is also part of the

complex of closely related taxa that is distributed through northern Vietnam, Laos, northern

Thailand and Yunnan and Guangxi in southern China (Section Stangerioides) Within this

section, a subgroup that may be a natural group is defined by its robust habit with a stout, erect,

aerial trunk This subgroup is mainly Chinese (including C hainanensis C J Chen, C tai-

waniana Carruth and, C diannanensis Z T Guan & G D Tao), with C dolichophylla the

only member of the group known to extend beyond China

Distribution and habitat: Locally frequent in more sheltered sites in deep shade in tall, closed evergreen forests, from near the Chinese border in the north and northwest to Ben En National Park in Thanh Hoa Province in the south, extending northwestward to a very short way into eastern Yunnan Province (Fig 2) This species occurs on loamy soils over limestone, shale, schist, or granite, in closed evergreen forests, although today these are often reduced to scrubby regrowth and bamboo scrub

A population occurring west of the city o f M o c Chau has narrow pinnae with slender bases, short to medium petioles, and small seeds and is interpreted as a zone of intergradation with

Cycas collina, which is abundant in higher country to the west (specimens cited above under

C collina) Plants observed in cultivation around Vo Nhai and Yen Son Districts, Thai Nguyen

Province, were intermediate in form between C dolichophylla and C ferruginea and have been interpreted as hybrid individuals In this region, C ferruginea is abundant on steep, ex- posed limestone faces, and C dolichophylla is abundant in adjacent closed forests on deep

heavy soils (specimens cited below) Plants observed in cultivation in villages west of Thai Nguyen and said to have been collected locally were morphologically intermediate between

C dolichophylla and C bifida

Conservation status: Not considered to be at risk IUCN Red List status L R cal

Etymology: From the Greek dolichos, long, and phyllon, leaf, referring to the distinctively

long leaves of this species

Selected specimens examined: VIETNAM Bae Can: Bac Can city, cult., coll from ca 13 km to SE,

15 Mar 1999, Hill 5036 & Loc (HN, NSW); Cho Moi, Tan Son, Nam Dat (22006'09 " N, 105~ '00" E), alt ca 400 m, 16 Mar 1999, Hill 5037, 5038 & Loc (HN, NSW) Cao Bang: Nguyen Binh, Huo Tham,

Be Nuoc (22o33'40 " N, 106~ E), alt ca 400 m, 14 Mar 1999, Hill 5032 & Loc (I-IN, NSW) Ha

Giang: Vi Xuyen, Viet Lam, Muc, 28 km S of Ha Giang city, cult in village (22o37'26 " N, 104~ ' 18" E),

coll ca 3 km to NW, 26 Mar 1999, Hill 5068 & Loc (I-IN, NSW); Vinh Tuy, SE edge of Vinh Tuy townlet (22o14'55" N, 104056'26 " E), cult in garden, coll ca 20 km SW, 26 Mar 1999, Hill 5069 & Loc (HN,

from steep limestone ridge behind village, 23 Mar 1999, Hill 5064 & Loc (HN, NSW); Phong Tho, Muong So, Phuong Lanh (22~ '37" N, 103o20'46" E), 24 Mar 1999, Hill 5065 & Loc (HN, NSW) Lao

Cai: Lao Cai city, cult., coll 10 km to W or SW (ca 22~ N, 104004 ' E), 24 Mar 1999, Hill 5066 & Loc (HN, NSW); Bao Yen, Thuong Ha, third village (22016'33 " N, 104023'55 " E), 25 Mar 1999, Hill 5067 &

Loc (I-IN, NSW) Ninh Birth: Cuc Phuong, 29 Dec 1994, Hi~p 2029 (HN); Nho Quan, Cuc Phuong National Park, near gate, cult on old village site, thought to have been coll locally, 18 Mar 1999, Hill

5049 & Loc (HN, NSW); Nho Quan, Cuc Phuong National Park, near Bong (20051'25" N, 105~ E),

18 Mar 1999, Hill 5051 & Loc (HN, NSW); Nho Quan, Cue Phuong National Park, cult in village at entrance gate, coll nearby, 19 Mar 1999, Hill 5052 & Loc (HN, NSW) Son La: Moc Chau, Van Ho, Hang Trung, 20 km E ofMoc Chau (20047'37 " N, 104046'32 " E), 21 Mar 1999, Hill 5057 & Loc (l-IN, NSW)

Thai Nguyen: Vo Nhai, Lau Thuong, Lung Hang, cult near house, coll 500 m to E (21043'47 " N,

106000'27" E), 16 Mar 1999, Hill 5041, 5042 & Loc (HN, NSW) Thanh Hoa: Nhu Xuan, Ben En National Park, 13 Oct 1996, Hi~p 2116, 2117, 2118 (I-IN); Nhu Thanh, Hal Van, Xuan Lai (19036'32" N,

105~ '' E), 19 Mar 1999, Hill 5054 & Loc (HN, NSW); Ngoc Lac, Mirth Son, Minh Chau, cult in

village, coll nearby (20o02'22" N, 105~ E), 20 Mar 1999, Hill 5055 & Loc (HN, NSW); Lang

160 THE BOTANICAL REVIEW

Chanh, Dong Luong, Thung (20011'42" N, 105~ E), 20 Mar 1999, Hill 5056 & Loe (HN, NSW) Tuyen Quang: Chiem Hoa, Yen Nguyen, Dong Vang, 29 Mar 1996, Yang & HMp 768 (HN); 31 Mar

1996, Yang & HMp 774 (HN); Na Hang, Pac Ban, Nam Chang, 30 Mar 1996, Yang & Hi~p 769, 770 (HN); Hi~p 2083 (HN); Yen Son, Tien Bo, Goc Thi (21~ N, 105021'23" E), cult in garden, coll

from wooded hills close by, 17 Mar 1999, Hill 5046 & Loc (HN, NSW)

CHINA Yunnan: Hekou County, An Gia He District, cult in Ma Chang village, brought from Yang

Hui village, Hong 329, Chen, Hill & Stevenson, 4 Ju12000 (YUN, NSW, NY, PE); Hekou County, Nan Xe Tung municipality, Xiao Xi He village, 132 dam, Hong 332, 333, Chen, Hill & Stevenson, 4 Jul 2000

(YUN, NSW, NY, PE)

Hybrid swarm: Cycas dolichophylla • Cycas ferruginea

VIETNAM Thai Nguyen: Vo Nhai, Lau Thuong, Lang Hang, cult near house, coll 500 m to E (2l~ N, 106000'27 " E), 16 Mar 1999, Hill 5039, 5040 & Loc (FIN, NSW); Quang Son, Dong Hai,

cult in gardens (21~ '50" N, 105~ ' 12" E), coll from steep limestone cliffs 30@-400 m to W, 16 Mar

1999, Hill 5045 & Loc (I-IN, NSW)

Hybrids: Cycas dolichophylla X Cycas bi3qda

VIETNAM Thai Nguyen: 15 km NW of Thai Nguyen city sight record, no voucher, H T Nguyen

& K D Hill, 17 Jan 2000

11 CYcAS MICHOLITZII Dyer, Gard Chron 38: 142-144, figs 48-49 1905

TYPE: Annam, Micholitz s.n (HOLOTYPE: K, 4 sheets)

Dyerocycas mieholitzii (Dyer) Nakai, Ordines, familiae, t r i b i , , et combinationes a Prof

Nakai-Takenosin adhuc novis edita 208 1943; as mischolitzi

Epicycas micholitzii (Dyer) de Laub., in de Laub & Adema, Blumea 43: 389 1998 Literature: Leandri (1931); Ho and Duong (1960); Smitinand (1971)

Illustrations: Thiselton-Dyer (1905); Prain (1909); Raffill (1912); Smitinand (1971) Stems acaulescent, 1 0-15 cm diam at narrowest point, 2~5 leaves in crown Leaves bright

green, semiglossy or dull, 110-240 cm long, moderately keeled (opposing pinnae inserted at 90-120 ~ on rachis), with 18-56 pinnae, with white tomentum shedding as leaf expands; rachis

consistently terminated by paired pinnae Petiole 50-105 cm long (40-55% of total leaf), peti- ole glabrous, spinescent for 70-95% of length Basalpinnae not gradually reducing to spines, 230-330 mm long Median pinnae dichotomously branched, strongly discolorous, 230-360

mm long, 11-19 mm wide, inserted at 60 ~ to rachis, narrowed to 2-3 mm at base (to 10-20%

of maximum width), 3 5 ~ 0 mm apart on rachis; section flat; margins flat; apex softly acumi-

nate, not spinescent; midrib raised above, flat below Cataphylls narrowly triangular, soft, pi- lose, 60-80 mm long, articulated Microsporangiate cones narrowly ovoid or fusiform, yellow, 15-25 cm long, 3-5 cm diam Microsporophyll lamina soft, not dorsiventrally thickened, 13-

! 8 mm long, 7-11 mm wide, apical spine prominent or rudimentary, sharply upturned, 1~5 mm

long Megasporophylls deeply pectinate Seeds ovoid; fibrous layer absent; sclerotesta verru-

cose; spongy layer absent

Historical notes: This remarkable species was described by the English botanist Sir Will-

iam Thiselton-Dyer in 1905 Material apparently collected by Micholitz in Annam (northern Vietnam), came into possession of Henry Ridley, director of Singapore Botanic Gardens, in

1904 He proposed that it should be the type of a new genus (in correspondence to Thiselton- Dyer) Thiselton-Dyer received material of Micholitz's collections from Sander & Sons in

1905 and from Ridley (including botanical drawings by an artist on Ridley's staff) at about the

same time He astutely recognized that this species belonged with the genus Cycas, despite the

tmusual leaf He described it as a new species in 1905, noting the similarities with the specimen

he had earlier described as Cycas rumphii var bifida but not combining the two Subsequent

authors until now have combined the two, although closer inspection in recent times has now

shown them to be distinct (see C bifida)

Quite large numbers of plants were collected by Micholitz and imported to England by Sander & Sons, and the species created considerable interest in European horticultural circles (Prain, 1909; anon., 1910; Raffill, 1912) Male and female coning was documented at Kew (anon., 1910; Raffil, 1912), but most of the imported plants were apparently lost in the general decline in interest in exotic ornamental horticulture that followed World War I The Dublin Botanic Gardens is the only collection known to still have a single plant from these collections (in 1998)

Distinguishing features: The most immediately striking feature of this species is its di- chotomously divided pinnae However, this also occurs in several related taxa and in a horti-

cultural form of Cycas revoluta that is popular in Japan Its subterranean habit, small, soft

microsporangiate cones, loose, freely peeling sarcotesta lacking a fibrous layer, and verrucose

sclerotesta are also all features shared by related species (Section Stangerioides) Within the group of related species with divided pinnae, C micholitzii is distinguished by its short leaves

with dull, comparatively short and narrow pinnae that are dichotomously divided very near to

or at the base and its small microsporangiate cones with distinct short, slender spines on the microsporophyll tips

Distribution and habitat: The Annam Highlands region of central Vietnam and eastern Laos, mostly in low, scrubby, but fairly dense woodland, extending into drier monsoon savanna forests (Fig 8)

Conservation status': Virtually unknown from the time of Micholitz until the past few years, this species has been severely reduced in numbers both by collecting and by unrestrained agri- cultural and forestry development The rarity, combined with the unusual habit, makes it a highly sought plant by collectors It is still, however, frequent in many places and is not consid- ered to be at risk in the short term IUCN Red List status LR cd

Selected specimens examined: VIETNAM Dae Lae: Buon Chet, Schmidt s.n (P), Ban Me Thuot,

Schmidt 872 (P).Gia Lai: Hau Bon (Cheo Reo), Dournes s.n., Apr 1967 (P); 10 km W of An Khe, Nat

Geog Soc Exped VII 1461, 19 Apr 1995 (HN, P); Kong Na Nung, Ka Nae, Dzu s.n., Oct 1991 (P); An Khe, Ha Tam, 1 Nov 1994, Yang, Ban & Lindstrom SLY536 (HN) Kon "rum: Dac To, Tan Canh, 8 May

1996, HiOp 2088 (HN); Sa Thay, Ro Koy (14027'09 " N, 107036'42 " E), 7 Apr 2000, P K Loc P8568

(FIN, HNU, MO)

12 CYCAS BIFIDA (Dyer) K D Hill, comb nov

BASIONYM: Cycas rumphii var bifida Dyer, J Linn Soc., Bot 26: 560 1902

TYPE: China: Guangxi: Lighthouse pagoda rockhills, Ltmgchow [Longzhou], Morse 273,

Dec 1896 (HOLOTYPE: K, 2 sheets)

Literature." Cheng et al (1975), as Cycas micholitzii; Chen and Stevenson (1999), as Cycas

micholitzii

Illustrations: Wang (1996), as Cycas micholitzii

Stems acaulescent, 10-30 cm diam at narrowest point, 2-5 leaves in crown Leaves bright

green, semiglossy, 200-500 cm long, slightly keeled to flat in section (opposing pinnae in- serted at 120-180 ~ on rachis), with 40-80 pinnae, with white and orange tomentum shedding

as leaf expands; rachis usually terminated by paired pinnae Petiole 110-160 cm long (35-50%

of total leaf), glabrous, spinescent for 90-100% of length Basal pinnae not gradually reducing

to spines Median pinnae dichotomously branched up to three times, strongly discolorous,

300~00 mm long, 18-25 mm wide, inserted at 45-70 ~ to rachis, decurrent for 10-15 ram,

162 THE BOTANICAL REVIEW

fusiform, yellow or cream, 35-55 cm long, 6-8 cm diam Microsporophyll lamina soft, not dorsiventrally thickened, 17-28 mm long, 13-16 mm wide, fertile zone 1 4 2 5 mm long, sterile apex 2-3 mm long, level, apical spine absent Megasporophylls 7-11 cm long, brown-tomen- tose; ovules 2-6, glabrous; lamina ovate, 35-100 mm long, 25-50 mm wide, deeply pectinate, with 12-15 soft lateral spines 18-50 mm long, 2-3 mm wide, apical spine distinct or not distinct from lateral spines, 15-70 mm long, 3-8 mm wide at base Seeds flattened-ovoid, 25

mm long, 20 mm wide; sarcotesta yellow, not pruinose, 2 mm thick; fibrous layer absent; sclerotesta verrucose; spongy layer absent

Historical notes: This species was first recognized as a distinct taxon in Western literature

by the English botanist Sir William Thiselton-Dyer in 1902, who described it as Cycas rumphii

var bifida, on the basis of a leaf fragment collected by H B Morse in the Longzhou District of

southern Guangxi in 1896 Thiselton-Dyer later received material apparently collected by

W Micholitz in Annam (northern Vietnam) from Sander & Sons in 1905 and material from Henry Ridley of the Singapore Botanic Gardens at about the same time He described this as a

new species C micholitzii in 1905, noting the similarities with the specimen he had earlier described as C rumphii var bifida but not combining the two Subsequent authors regarded

them as the same species until recent studies showed them to be distinct

Distinguishing features: The most immediately striking feature of this species is its di-

chotomously divided pinnae However, this also occurs in several related taxa and in a horti-

cultural form of Cycas revoluta that is popular in Japan Its subterranean habit, small, soft

microsporangiate cones, loose, freely peeling sarcotesta lacking a fibrous layer, and verrucose

sclerotesta are also all features shared by a wider group of related species (Section Stangerioides) Within this group of related species, C bifida is distinguished by its long leaves with glossy,

thin-textured, comparatively long and broad pirmae that are dichotomously divided very near

to the base It is most similar to C micholitzii from central Vietnam and can be distinguished by

its larger stature, longer, broader, more lax, and glossier pinnae, and larger microsporangiate cones with mostly nonspinescent microsporophylls This species has no connection whatso-

ever with Cycas rumphiL a seashore species from section Cycas that occurs in Indonesia

Distribution and habitat: Southern Guangxi Province in China and Lang Son in far north-

eastern Vietnam (Fig 8) Locally abundant, but many populations are now depleted, in low, scrubby, but fairly dense mixed evergreen and deciduous or bamboo woodland, often on red

terra rosa soils on and around steep, karst limestone outcrops but also on loamy soils over

shales and metasandstones This species is apparently sympatric with Cycas multipinnata in

several populations in China, and a range of morphologically intermediate forms that can be

interpreted as a hybrid swarm has been observed (see C longipetiolula, excluded names, be- low) Hybrids are also known with C diannanensis in China and C dolichophylla in Vietnam The type of C multifrondis is thought to represent a hybrid with a simply pinnate species of

unknown identity (see excluded species below)

Conservation: This species has been severely reduced in numbers both by collecting and by

unrestrained agricultural and forestry development Its rarity, combined with its unusual habit, makes it a very highly sought plant by collectors It is still, however, frequent in many places, especially in Vietnam, and is not considered to be at risk in the short term IUCN Red List status VU A2c

Selected specimens examined: VIETNAM Lang Son: Trang Dinh, Chi Lang, Keo Quang (22~

N, 106027'22" E), 13 Mar 1999, Hill 5027, Loc & Dzu (HN, NSW); Binh Gia, Thien Hoa, Thien Thua, 28 Mar 1996, Yang & Hi~p SL Y764 (HN) Cao Bang: Thach An, Duc Xuan, Tuc Nga (22022 ' 18" N, 106~ E), alt ca 200 m, 13 Mar 1999, Hill 5028, 5030 & Loc (HN, NSW); Thach An, Tong Con, 3 Dec 1996,

Loc et aL CBL853 (HN) Tuyen Quang: Son Duong, Hop Thanh, Dung Dai, HiOp 4116 & Hill, 15 Jan

2000 (HN, NSW); Yen Son, Tien Bo, Goc Thi, cult in garden, coll from wooded hills in general vicinity

(21o44'37 " N, 105~ '23" E), 17 Mar 1999, Hill 5047 & Loc (HN, NSW)

CHINA Guangxi: cult in nursery of Nanning Forestry Research Center, Nanning, coll Longzhou

County, 7 Nov 1998, Chen, Zhong & Hill 3 (NSW, PE); cult in Longzhou city park, coll Longzhou County, 21 Nov 1998, Chen, Zhong & Hill 35 (NSW, PE) Yunnan: Hekou County, Hong 347, Chen, Hill

& Stevenson, 6 Jul 2000 (YUN, PE)

Hybrids: Cycas multifrondis X Cycas multipinnata

CHINA Yunnan: Gejiu County, Yuanjiang River valley, D Y Wang & H Peng 5523, 23 Apr 1994 (SZG; holotype of Cycas longipetiolula) Hekou County, Hong 350, Chen, Hill & Stevenson, 6 Jul 2000 (YUN, PE)