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| Photo Dennis Stevenson
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| The Cycad Pages
| | Microcycas calocoma
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- Microcycas calocoma (Miq.) A. DC., Prodr. 16(2): 522-548 (1868). BAS
Zamia calocoma Miq., in Van Houtte, Fl. Serres 7(6): 141 (1852).
- TYPE: Cuba, 1861-1864, Wright 3193 (neo G-DC, iso BM, G, GH, K, LE, MO, NY, P; fide Stevenson & Sabato 1986) OR cult hort. Amstel ex Cuba, Miquel s.n.
Etymology: The genus name literally means small Cycas which is
a misnomer as discussed below.
The specific epithet refers to a 'beautiful crown of leaves'.
Common name(s): Palma corcho, Cuba.
from the Greek calos, beautiful, and coma, hair.
Historical notes:
Microcycas calocoma was originally described as Zamia calocoma by
Dutch botanist
F.A.W.
Miquel.
in 1851
and placed in its own section of Zamia, i.e. Zamia section
Microcycas. In 1861, Miquel (in
Prodromus Systematis
Cycadearum,
p.26) thought it was possibly a new genus based upon vegetative features but
because he had seen no cones reserved judgement. Subsequently,
Alphonse De Candolle in
1868
described the genus Microcycas and in doing so used Miquel's suggestion
and sectional name. Clearly without reproductive material Miquel's original
intent was to use Microcycas to refer to a small cycad not a small
Cycas.
Distinguishing features:
The obviously truncated leaves with drooping leaflets that are also
observable in juvenile plants distinguish this cycad.
The robust arborescent habit and the
large male and female cones with the two apical protuberances on the
sporophylls are also distinctive.
Distribution and habitat:
Endemic to Western Cuba. Microcycas grows in varied habitats ranging
from montane forest at 250 meters to lowland limestone or grassland and scrub
at 50 meters.
Conservation status:
Microcycas should be considered endangered in the wild it would appear
mainly because of habitat destruction and most importantly because it appears
to set little or no seed. This in turn appears to be because the pollinator is
no longer present perhaps as a result of pesticide use. The is not recent but
goes back to observations published in 1942 by Foster and San Pedro (Mem. Soc.
Cubana Hist. Nat. "Felipe Poey" 16: 105-121). 1997 IUCN Red List of Threatened
Plants Category V,I,E.
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| Photo Dennis Stevenson
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| Photo Dennis Stevenson
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Description:
Stems arborescent, to 10 m, tall, 60 cm diam. at base.
Cataphylls to 12 cm long, grey-pilose.
Leaves 10-50, 0.6-1.2 m long, appearing apically truncate; petiole 0.08- 0.1 m long, not prickled; rachis bearing 50-80 pairs of leaflets, not prickled.
Leaflets linear lanceolate, margin entire, attenuate basally, acute apically, median ones 15-25 cm long and 0.8-1.0 cm wide, reflexed below the plane of the rachis.
Pollen cones 1, cylindrical, shortly pedunculate, yellowish brown, 25-30 cm long and 5-8 cm in diameter, peduncle 2-4 cm long.
Seed cones broadly cylindrical, shortly pedunculate, yellowish brown, 50-90 cm long and 13-16 cm in diameter, peduncle 2-4 cm long. Sporophylls with two rounded apical protuberances.
Seeds ovoid, 3.5-4 cm long, 2-2.5 cm in diameter, sarcotesta pink to red.
2n = 16