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| Photo Ken Hill
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| The Cycad Pages
| | Cycas javana
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- Cycas javana (Miq.) de Laub., in D.Y. Wang, Cycads in China: 65 (1996). H—L
Cycas circinalis var. javana Miq., Monogr. Cycad.: 28. t. 1, fig. t & u, t. II, fig. E1 (1842). H—L
- TYPE: Indonesia, Java, Blume 1089 (holo L, 2 sheets).
Etymology:
From the island of Java, with the Latin suffix -ana, a
connection, referring to its occurrence on and initial collection
from Java.
Historical notes:
Described in 1842 as a variety of C. circinalis by Dutch
botanist Miquel. Miquel later subsumed
this variety into C. rumphii, and no further note was made
of it until it was raised to specific status in 1996
by de Laubenfels (in Wang, 1996).
Distinguishing features:
The long, narrowly triangular megasporophyll apex with numerous distinct slender
lateral spines separate this species from otherwise similar forest
species from Malaysia (C. macrocarpa and eastern Indonesia
(C. scratchleyana).
Distribution and habitat:
Primarily a Javan species, extending to southern Sumatra and possibly
the western Sunda Islands, occurring in closed forest on slopes and ridges
from low to middle elevations, mostly on volcanic soils.
Conservation status:
Much of the primary forest habitat has been cleared or degraded in recent
decades, and the habitat loss continues today. This species is poorly
known but apparently under considerable threat.
IUCN (1994)
Red List status DD/EN?.
Description:
Stems arborescent.
Leaves bright green, highly glossy, flat (not keeled) in section (opposing leaflets inserted at 180° on rachis), with brown tomentum shedding as leaf expands; terminated by a spine or paired leaflets; 6 mm long. Petiole 40-60 cm long, glabrous, spinescent for 40-90% of length. Basal leaflets not gradually reducing to spines.
Median leaflets simple, strongly discolorous, 240-370 mm long, 10-15 mm wide, narrowed to 2.5-6 mm at base (to 20-35% of maximum width); median leaflets section flat; margins slightly recurved; apex acute, not spinescent; midrib raised above, raised below.
Cataphylls linear, soft, pilose, articulated.
Pollen cones fusiform; microsporophyll lamina firm, not dorsiventrally thickened, apical spine prominent, sharply upturned.
Megasporophylls 24-36 cm long; ovules 2-6, glabrous; lamina lanceolate, 60-95 mm long, 11-21 mm wide, regularly dentate, with 12-30 pungent lateral spines 1-2 mm long, 1 mm wide, apical spine distinct from lateral spines, 10-30 mm long, 1.5-3 mm wide at base.
Seeds ovoid; fibrous layer absent; sclerotesta smooth. Spongy endocarp present.