Isosyntypes (K)
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Cycas zeylanica

Cycas zeylanica (J. Schust.) A. Lindstr. & K.D. Hill, Novon 12(2): 238-239 (2002). L—G


Etymology: From Zeylona, the Latinised rendering of Ceylon (Sri Lanka), from where the type of this species was collected. (as C. rumphii)

Literature: Trimen 1898 (as C. rumphii), Rendle 1900 (as C. rumphii), Raizada & Sahni 1960 (as C. rumphii).

Historical notes: Collection detail cited was "Ceylon: Thwaites 1866 n. 3862 in Herbar. Barbey-Boissier." Schuster's herbarium and types were in B, and were destroyed in WW2. The Barbey-Boissier herbarium and types are in G, including this collection. Three sheets exist, with microsporophylls, megasporophylls and leaflets, each on a separate sheet. More than one plant is clearly involved, and it is impossible at this stage to associate the leaf specimen with either of the fertile specimens. These may not have been the specimens examined by Schuster, as they have no annotations. The sheet bearing the megasporophylls has been designated the lectotype.

Distinguishing features: Allied to both C. thouarsii and C. litoralis, sharing the characters of seeds lacking an apical wing and microsporophylls with an apical spine. C. zelanica is distinguished by the abundant long and pungent cataphylls and widely spaced leaflets that show no signs of glaucousness.

Distribution and habitat: Known from Sri Lanka, where apparently a now rare species in southern coastal regions, and the Andaman group, where more abundant.

Conservation status: This species is poorly known but apparently under considerable threat, especially in Sri Lanka. IUCN (1994) Red List status DD/EN?.

Description:

Stems arborescent. 30 leaves in crown.

Leaves bright green or deep green, semiglossy, 140-190 cm long, flat (not keeled) in section (opposing leaflets inserted at 180° on rachis), with 70-100 leaflets, with white or orange tomentum shedding as leaf expands; rachis consistently terminated by paired leaflets. Petiole 50-70 cm long (30-40% of total leaf), petiole glabrous, spinescent for 30-100% of length. Basal leaflets not gradually reducing to spines.

Median leaflets simple, strongly discolorous, 180-300 mm long, 12-15 mm wide, inserted at 50-60° to rachis, narrowed to 6-7 mm at base (to 40-50% of maximum width), 22-27 mm apart on rachis; median leaflets section flat; margins slightly recurved; apex acute, not spinescent; midrib raised above, flat below.

Cataphylls linear, pungent, pilose, 100-120 mm long, persistent.

Pollen cones fusiform; microsporophyll lamina firm, not dorsiventrally thickened, 35-45 mm long, 17-19 mm wide, apical spine prominent, sharply upturned, 3-10 mm long.

Megasporophylls 17-30 cm long; ovules 2-4, glabrous; lamina lanceolate, 60-120 mm long, 10-17 mm wide, obscurely dentate, with 6-12 soft lateral spines 0-1 mm long, 1-2 mm wide, apical spine distinct from lateral spines, 40-60 mm long.

Seeds flattened-ovoid; sarcotesta orange-brown; fibrous layer absent; sclerotesta smooth. Spongy endocarp present.


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Written and maintained by Ken Hill 1998-2010
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