 |
Photo Knut Norstog
|
 |
The Cycad Pages
| Zamia roezlii
| |
- Zamia roezlii Linden, Catalogue des Plantes Nouvelles 9: 10 (1873).
- "TYPE: the illustration: Ill. Hortic. 20: pl. 133-134, 1873 (fide Stevenson & Sabato 1986)."
 |
Photo Dennis Stevenson
|
Etymology:
The specific epithet honors Benedict Roezl a prodigious plant collector
who traveled throughout Mexico, Central America and South America in the
of the latter half of the nineteenth century and who first collected
the species.
Historical notes:
In the past there has been some confusion concerning the identity of
Z. roezlii
(
Norstog, 1986;
Sabato, 1990)
and the species has
been referred to as Z. chigua. The reason for this was the
lack of typification of various Zamia species and the use of
the common name of "chigua" by indigenous people in the Choco of
Colombia. The common name "chigua" is apparently applied to several
species of Zamia. As a result of this confusion,
Z. roezlii Linden was thought to be Z. chigua as
discussed by Norstog in "Zamia chigua, a case of mistaken
identity?" in Fairchild Tropical Garden Bulletin 41(1): 6-13. 1986.
Distinguishing features:
Zamia roezlii is readily distinguishable from other species with
deeply grooved leaflets by its the falcate, linear, entire leaflets.
Z. roezlii is the largest South American Zamia and is
unmistakable with its massive trunk, leaves, and strobili.
This species would appear to part of a complex composed of
Z. dressleri, Z. neurophyllidia, and Z. skinneri
in Panama, Z. amplifolia and Z. roezlii in the Choco of
Colombia and adjacent Ecuador, and Z. wallisii in Northern
Antioquia, Colombia. This grouping is based upon the common occurrence
of the plicate appearance of the leaflets of these species. This
character, along with simultaneous rather than sequential leaf
production, prompted
Regel (1876)
to erect the segregate genus
Aulacophyllum. However, no other synapomorphies have been
found to support Aulacophyllum as a genus (Sabato, 1990).
Moreover, the distinction between simultaneous and sequential
leaf production in Zamia seems problematic at best.
Distribution and habitat:
Along coastal Choco, Colombia and contiguous coastal Ecuador at near sea level.
Conservation:
Zamia roezlii is locally abundant and produces very large seed
cones and thus numerous seeds and seedlings. However, seed cones are
produced by arborescent plants and under continual disturbance seed
production will be severely diminished resulting in high vulnerability.
1997 IUCN Red List of Threatened Plants
Category R,II,V.
 |
Photo Calaway Dodson
|
 |
Photo Dennis Stevenson
|
Description:
Stem arborescent, to 7 m tall.
Leaves 5-10, 1-3 m long; petiole 0.5-1 m long, sparsely to
densely prickled; rachis with 10-20 pairs of leaflets, occasionally with
a few prickles in the lower third.
Leaflets linear-lanceolate, falcate, grooved between the veins
on the adaxial surface, cuneate basally, acute apically, margins entire,
30-50 cm long, 12-15 cm wide.
Pollen cones cream to tan, cylindrical to elongate-cylindrical,
20-30 cm long, 4-6 cm diam.
Seed cones brown, short pedunculate, cylindrical to ovoid
cylindrical, 30-60 cm long, 10-20 cm diam.
Seeds red, ovoid, 1.5-2.5 cm diam.
2n = 22, 24, 25, 26.
The Cycad Pages
|
|
© 1998-2012 Royal Botanic Gardens Sydney
Written and maintained by Ken Hill 1998-2010
Maintained by Leonie Stanberg and Dennis Stevenson 2010-2012
This site is currently not being maintained
|