|Photo Ken Hill
|The Cycad Pages
- Cycas tanqingii D.Yue Wang, "Cycads in China: 134, fig. 4" (1996). H—SZG
- "TYPE: China, Yunnan, Luchun County, D.Y. Wang 5538 (holo SZG, iso NF)."
|Photo Ken Hill
director of the Shenzhen Fairy Lake Botanic
Garden at the time this species was described.
Discovered by Chinese and Western botanists only in the 1990's.
The robust habit with a stout aerial trunk, long leaves with long petioles,
large pollen cones, small megasporophylls
and large seeds distinguish this species within Section Stangerioides.
It is at present very poorly known and may be confused with
C. dolichophylla. C. tanqingii
differs from C. dolichophylla in the longer and more widely spaced
leaflets that are not broadbased and rounded at the base, and the longer
petioles. It is also similar to C. chevalieri from Laos and Vietnam,
differing in the overall much larger stature.
Distribution and habitat:
Remote and mountainous country in south-eastern Yunnan Province, China,
also reported by local villagers and forestry workers to occur across the
border in Vietnam,
in closed evergreen forest. Much of this forest has been cleared for
agiculture in recent decades, and, in general, the forest remains only
on precipitously steep sites that are unsuitable for any kind of cultivation.
Good populations of this species still occur in these sites.
There is no immediate threat of extinction, although the severe depletion
of populations over past decades indicates that conservation action is
appropriate, and this species is regarded as
IUCN Red List category VU A2c.
Stems arborescent or acaulescent, 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 leaflets inserted at 170-180° on rachis), with 100-120 leaflets, with orange tomentum shedding as leaf expands; rachis consistently terminated by paired leaflets. Petiole 70-160 cm long (30% of total leaf), petiole glabrous, spinescent for 100% of length. Basal leaflets not gradually reducing to spines.
Median leaflets simple, strongly discolorous, 300-450 mm long, 15-22 mm wide, inserted at 65-85° to rachis, 15-27 mm apart on rachis; section flat; margins slightly recurved; apex aristate, not spinescent; midrib raised above, raised below.
Cataphylls narrowly triangular, soft, pilose to densely floccose, persistent.
Pollen cones fusiform, 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 prominent, sharply upturned, 1.5-2 mm long.
Megasporophylls 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 lateral spines 15-40 mm long, 1-3 mm wide, apical spine distinct or 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 endocarp absent.