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| Photo Ken Hill
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| The Cycad Pages
| | Cycas segmentifida
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- Cycas segmentifida D.Yue Wang & C.Y. Deng, Encephalartos 43: 11-14 (1995). H—SZG
- TYPE: cultivated, South China Botanical Garden, Guangzhou, China, D.Y. Wang & H. Peng 2967, 16 May 1994 (holo SZG, iso FTG, GZAC, NF, NSW, XIN).
[NSW]
Cycas longiconifera H.T. Chang, Y.C. Zhong & Y.Y. Huang, Acta Sci. Nat. Univ. Sunyatseni 37: 6 (1998). H—SYS
- TYPE: China, Guangxi, Baise, alt. 850 m, in calceo-saxo, Y.C. Zhong 8771, 26 Mar 1998 (holo SYS).
Cycas multifida H.T. Chang & Y.C. Zhong, Acta Sci. Nat. Univ. Sunyatseni 36: 70 (1997). H—SYS
- TYPE: China, Guanxi, Xiling, in arenoa-saxa, alt. 780 m, Y.C. Zhong 80196, 27 Jun 1995 (holo SYS).
Cycas xilingensis H.T. Chang & Y.C. Zhong, Acta Sci. Nat. Univ. Sunyatseni 36: 69 (1997). H—SYS
- TYPE: China, Guanxi, Xiling, alt. 880 m, Y.C. Zhong 80866, 18 Jul 1994 (holo SYS).
Etymology:
Latin, segmentifida,
Literature:
Wang 1996.
Illustrations:
Wang 1996
Historical notes:
Named in 1995 by Chinese botanists
D.Y. Yang and
C.Y. Deng.
Distinguishing features:
Within the group of Chinese cycads with soft pollen cones, loose, freely
peeling sarcotesta lacking a fibrous layer and rugose sculpting of the
sclerotesta (Section Stangerioides), this species is distinguished
by the small seeds, broad leaflets with flat or undulate margins, and
leaflets that are flat and not twisted on the rachis.
Distribution and habitat:
An extremely widespread although severely depleted species through western
Guangxi, extending into southern Guizhou and eastern Yunnan, in both cases
to a limited extent. This species occurs on a range of substrates from limestone
to shale and schist, usually on steep slopes lower in valleys with some although
often skeletal soil cover. Vegetation ranges from closed evergreen forest to
mixed deciduous and evergreen woodland, although today is mostly severely
degraded to grassland or scrubby secondary regrowth.
Conservation status:
This species is moderately abundant over a considerable area in western Guangxi
province, but severely depleted. There is however no immediate threat of
extinction, although the severe depletion indicates that conservation action
is appropriate, and this species is regarded as
IUCN Red List category VU A2c.
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| Photo Ken Hill
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Description:
Stems arborescent to acaulescent, to 0.5 m tall, 10-23 cm diam. at narrowest point; 8-25 leaves in crown.
Leaves deep green, highly glossy, 120-280 cm long, flat (not keeled) in section (opposing leaflets inserted at 180° on rachis), with 80-190 leaflets, with orange tomentum shedding as leaf expands; rachis consistently terminated by paired leaflets. Petiole 40-140 cm long (30-50% of total leaf), petiole glabrous, spinescent for 90-100% of length. Basal leaflets not gradually reducing to spines, 70-290 mm long.
Median leaflets simple, strongly discolorous, 120-420 mm long, 9-20 mm wide, inserted at 50-80° to rachis, decurrent for 4-7 mm, narrowed to 3-7 mm at base (to 30-50% of maximum width), 11-24 mm apart on rachis; median leaflets section flat; margins flat; apex acute, not spinescent; midrib raised above, raised below.
Cataphylls narrowly triangular, soft, pilose, 70-100 mm long, persistent.
Pollen cones fusiform, yellow, 30-60 cm long, 5-12 cm diam.; microsporophyll lamina soft, not dorsiventrally thickened, 20-30 mm long, 15-18 mm wide, fertile zone 17-27 mm long, sterile apex 3 mm long, level, apical spine absent.
Megasporophylls 16-25 cm long, yellow-tomentose or brown-tomentose; ovules 4-8, glabrous; lamina orbicular, 80-130 mm long, 50-120 mm wide, deeply pectinate, with 16-44 soft lateral spines 20-70 mm long, 2-3 mm wide, apical spine distinct from lateral spines, 25-125 mm long, 8-20 mm wide at base.
Seeds subglobose, 28-35 mm long, 24-30 mm wide; sarcotesta yellow, not pruinose, 1.5 mm thick; fibrous layer absent; sclerotesta verrucose. Spongy endocarp absent.