Ceratozamia hondurensis

Family: Cycadae    苏铁

通用名称: 没有已知的

枝条抗寒性区: 10b     英国和美国的地带地图

鉴别:
Plant an understorey shrub. Stem 15-25 cm diam., acaulescent, solitary, covered by persistent cataphylls and leaf bases; cataphylls 4.5-6.5 cm long, 4.5-9 cm wide, triangular, stipulate, pubescent, wine red to purplish-maroon, base appressed, tip acuminate and erect to reflexed. Leaves to 20 or more per crown, 1.4-2.8 m long, erect to arching; venation circinate; emerging lanate, bright green, and slightly glaucous to non-glaucous; expanding to glossy lime green and glabrous; maturing to glossy dark green, later becoming covered with lichens and other epiphytes; rachis 80-180 cm long, 0.5-1 cm diam., terete, not twisted, armed with small prickles in lower half to two-thirds; 6-16 leaflet pairs, widely spaced, not fasciculate; basally keeled, medially and apically flat to slightly declinate; basally alternate, medially alternate to subopposite, apically subopposite to opposite; petiole 60-70 cm long, 1-2 cm diam., terete, lightly to moderately armed, non-glaucous to slightly glaucous, initially lanate, maturing sparsely pubescent or glabrous; leaf base 2.5-5.5 cm wide, stipulate, wine red to purplish-maroon, glabrous; leaflets 24-30 cm long, 9-13 cm wide (median), membranous, nearly symmetric to slightly asymmetric, oblanceolate, not falcate, flat to slightly convex adaxially, may be slightly upturned toward the edges; margins subrevolute, apically entire to slightly scalloped and smooth to slightly undulating; tip 1-2 cm long, slightly to moderately asymmetric, abruptly acuminate; articulation 0.5-1 cm wide, green, attenuate; veins 40-55, parallel, basally dichotomous, opaque, raised abaxially; eophylls typically with four equal-sized, slightly asymmetric, oblanceolate leaflets 4-5 cm long, 0.5-1 cm wide, basally slightly keeled, apically flat to slightly declinate. Microsporangiate strobilus 27-35 cm long, 4-5 cm diam., solitary, fusiform-cylindrical, erect, appearing sessile, green with numerous small black trichomes localised in the centre of each sporophyll; peduncle 1.8-3.5 cm long, 1.5-2.5 cm diam., lanate, not curved, hidden by surrounding cataphylls; microsporophylls 1-1.2 cm long, 0.7-1.2 cm wide, 0.5-0.6 cm tall, deltoid to cuneate, slightly peltate, spirally arranged in 18-20 columns and 75-85 rows, each bearing two outward and downward-turning, red-tipped horns 1-2 mm long, with one to several small, jagged protrusions between them; microsporangia in clusters of 2-5 equally distributed over entire unexposed abaxial surface, dehiscing longitudinally. Megasporangiate strobilus 18-21 cm long, 10-12.5 cm diam., solitary, cylindrical to barrel-shaped, dull green with a light scattering of small, blackish-brown trichomes, each sporophyll edged in darker, purplish-maroon trichomes, erect to leaning at maturity, not pendent; apex rounded-acute, 3-5 cm tall, consisting of reduced, sterile sporophylls; peduncle 5-15 cm long, 1.5-3 cm diam., densely tan to brown tomentose; megasporophylls 3.5-4.5 cm long, 4.2-5.5 cm wide, 2-2.5 cm tall, transversely hexagonal, spirally arranged in 12-14 columns and 10-12 rows, each bearing two stout, outward- and downward-turning, red-tipped horns 3-5 mm long, with one to several jagged protrusions between them; seeds 2-2.5 cm long, 1.5-2 cm diam., 200 or more per cone, smooth, ovoid to globose; sarcotesta white when ripe, quickly ageing to brown.

一般资料:
This species occurs in small, discrete, widely separated populations distributed along the North Coast region of Honduras. The largest known population consists of perhaps as many as 100 plants. This population is successfully reproducing, as seedlings were observed within 1 m of a mother plant bearing a disarticulating seed cone. Distributed along the Caribbean versant of the Cordillera Nombre de Dios, Department of Atlántida, Honduras. Plants typically grow at 20-600 m asl on steep river banks under dense canopy in wet tropical evergreen forest, but are occasionally found in the open near the stream bed.

分布:

最初是从, Honduras


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