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| Photo Ken Hill
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| The Cycad Pages
| | Cycas condaoensis
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- Cycas condaoensis K.D. Hill & S.L. Yang, Bot. Rev. 70(2): 178-179, fig. 14 (2004). H—K
- TYPE: Vietnam: Poulo Condor [Con Dao], L. Pierre 1722, Sep 1877 (holo K, iso A, L, NY).
Etymology:
From the occurrence as an endemic species on the Con Dao group.
Historical notes:
Placed in C. pectinata by
Leandri
(1931), overlooked by Ho in his general enumerations of Vietnamese plants
(1960,
1991),
and interpreted as C. inermis by
Hiep & Vidal (1996).
Distinguishing features:
C. condaoensis is somewhat
intermediate between C. siamensis and the C. pectinata
group in many characters. The small oblong male cone distinguishes
it from the C. pectinata group, while the glabrous leaf
with basal leaflets not gradually reducing to spines separates it
from C. siamensis.
The thick corky bark on the trunk and the inflated base with similar
thick corky bark are other similarities with C. siamensis,
although these features are also shared with C. pachypoda.
Pollen cones of C. condaoensis are intermediate in size between
those of C. siamensis and C. pachypoda.
Distribution and habitat:
Endemic on the Con Dao group
of islands. Several populations are known, mostly in
drier sites on sand accumulations, either beach dunes or wind-blown
beach sand deposits. Habitat ranges from low open shrubland to
dense tall shrubland or woodland.
Conservation status:
Not considered to be at risk in the short term, although of limited range
and population size.
IUCN (1994) Red List
status VU D2.
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| Photo Ken Hill
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| Photo Ken Hill
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Description:
Stems arborescent, to 0.2-2.5 m tall, 14-17 cm diam. at narrowest point; 12-70 leaves in crown.
Leaves bright green, semiglossy, 70-175 cm long, flat (not keeled) in section (opposing leaflets inserted at 180° on rachis), with 130-260 leaflets, with white or brown tomentum shedding as leaf expands; rachis usually terminated by paired leaflets. Petiole 20-50 cm long (15-30% of total leaf), petiole glabrous, spinescent for 0-60% of length. Basal leaflets not gradually reducing to spines, 25-120 mm long.
Median leaflets simple, strongly discolorous, 130-240 mm long, 7-11.5 mm wide, inserted at 60-75° to rachis, decurrent for 3-6 mm, narrowed to 2-3 mm at base (to 20-40% of maximum width), 5-17 mm apart on rachis; median leaflets section flat; margins slightly recurved; apex acute, not spinescent; midrib raised above, raised below.
Cataphylls narrowly triangular, pungent, thinly sericeous or lacking tomentum, 50-60 mm long, persistent.
Pollen cones narrowly ovoid, orange or brown to green, 26-31 cm long, 9-12 cm diam.; microsporophyll lamina firm, not dorsiventrally thickened, 30-50 mm long, 12-20 mm wide, fertile zone 23-36 mm long, sterile apex 7-11 mm long, level, apical spine prominent, sharply upturned, 4-5 mm long.
Megasporophylls 9-19 cm long, yellow-tomentose or brown-tomentose (pale); ovules 2-4, glabrous; lamina orbicular, 60-120 mm long, 35-75 mm wide, deeply pectinate, with 20-32 soft lateral spines 8-18 mm long, 1.5-2 mm wide, apical spine distinct from lateral spines, 25-60 mm long, 4-10 mm wide at base.
Seeds ovoid, 39-43 mm long, 33-36 mm wide; sarcotesta orange to yellow, not pruinose, 4-6 mm thick; fibrous layer present; sclerotesta smooth. Spongy endocarp absent.