Etymology: From the natural occurrence of this species in the Panzihua Prefecture of southern Sichuan Province, China, with the Latin termination -ensis, place of origin. Literature: Wang 1996. Illustrations: Wang 1996. Historical notes: Probably the most abundant Chinese cycad, although only relatively recently described. This species was named in 1981 by Chinese horticulturists Lin Zhou and Si-Yuan Yang, based on specimens that Yang and Bin Wu had collected near Dukou, now Panzhihua City, in 1979. In the same paper, Chinese botanists Li-Kuo Fu and Shu-Zhi Cheng from the Institute of Botany in Beijing described C. baguanheensis, based on collections by Yang and Wu from Baguan He, also near Panzhihua City, collected on the same expedition in 1979. It has been generally accepted subsequently, however, that the latter was merely a depauperate form of the former from a harsher site (Guan 1983, Zhou 1990). Distinguishing features: One of the most distinct of the Chinese cycads, characterised by the short stout trunks with a thick coat of orange-brown wool, the slender, hard cataphylls, the narrow, dull to semiglossy bluish leaflets and the small, orange-red seeds. Distribution and habitat: Known from southern Sichuan and northern Yunnan Provinces, typically in fairly dry, closed low woodland or shrubland thickets on moderately to steeply sloping sites. Soil is usually derived from limestone, although occurrences on shale and sandstone are known. As with all mainland Asian cycads, human population pressure has had considerable impact, and present distributions may represent a small fraction of the distribution of only a century ago. Conservation status: Although populations numbering hundreds of thousands were recently recorded (Zhou 1990), and two nature reserves have been designated for the protection of this species, this species must still be regarded as potentially at risk. Much of the habitat is under threat of clear cutting, and plants are being collected for sale as food, medicine and ornamentals, even within the reserves (Walters et al. 1995). IUCN Red List category LR,cd.
Description:
Stems arborescent, to 1-2(-3) m tall, 15-20 cm diam. at narrowest point; 30-80 leaves in crown. Leaves grey-green, semiglossy, 70-150 cm long, flat (not keeled) in section (opposing leaflets inserted at 180° on rachis), with 140-250 leaflets, with orange tomentum persistent below; rachis consistently terminated by paired leaflets. Petiole 7-25 cm long (15-25% of total leaf), petiole glabrous, spinescent for 50-70% of length. Basal leaflets not gradually reducing to spines, 50-70 mm long. Median leaflets simple, strongly discolorous, 120-230 mm long, 5-7 mm wide, inserted at 50-60° to rachis, decurrent for 4-6 mm, narrowed to 2-3 mm at base (to 35-45% of maximum width), 6-10 mm apart on rachis; median leaflets section flat; margins flat to slightly recurved; apex aristate, spinescent; midrib flat above, raised below. Cataphylls narrowly triangular, soft, densely floccose, 60-90 mm long, persistent. Pollen cones fusiform, yellow, 25-50 cm long, 8-14 cm diam.; microsporophyll lamina waxy, not dorsiventrally thickened, 40-60 mm long, 18-32 mm wide, fertile zone 30-40 mm long, sterile apex 8-11 mm long, deflexed, apical spine rudimentary, deflexed, 1-4 mm long. Megasporophylls 11-21 cm long, yellow-tomentose or brown-tomentose; ovules 1-5, glabrous; lamina orbicular, 70-150 mm long, 35-70 mm wide, deeply pectinate, with 23-40 soft lateral spines 10-40 mm long, 2-2.5 mm wide, apical spine not distinct from lateral spines. Seeds subglobose, 25-35 mm long, 22-30 mm wide; sarcotesta red to orange, not pruinose, 1.5 mm thick; fibrous layer absent; sclerotesta smooth. Spongy endocarp absent.
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