GENUS
Lepidozamia
K.D. Hill
- Lepidozamia Regel, Bull. Soc. Imp. Naturalistes Moscou 1: 182 (1857);
from the Greek lepidos a scale and Zamia a cycad.
- Type: L. peroffskyana Regel
- Catakidozamia W. Hill, in Hook., Gard. Chron. Nov. 1865:1107 (1865).
Type: C. hopei W. Hill
An endemic genus in eastern Australia, with two species.
Closely allied to the two large southern or Gondwanan cycad genera
in the family
Zamiaceae,
Macrozamia
also from Australia, and
Encephalartos
from Africa.
Individual species pages will have photographs, distribution maps,
descriptions, literature references and general notes on the species.
These are not yet all in place for all species, but the database
is slowly growing.
On species pages, click on thumbnail images to see full-screen images.
links to images of the protologue or original description
pertaining to the name.
- Broadest pinnae 17-30 mm wide, with 17-30 parallel veins --
Lepidozamia hopei
Broadest pinnae 7-14 mm wide, with 7-14 parallel veins --
Lepidozamia peroffskyana
Distinguishing characters:
- Leaves pinnate
- Leaflets lacking a midrib
- leaflets not articulated
- Leaflets inserted along upper midline of rachis
- Sporophylls not in vertical rows in cones
- Megasporophyll apices flattened and deflexed
Description:
Habit: dioecious palmlike shrubs with erect, aerial, cylindrical
stems, with many leaves. Leaf-bases shedding or persistent.
New leaves emerging in flushes.
Leaves: pinnate, spirally arranged, interspersed with cataphylls,
lower leaflets not reduced to spines. Petiole spine-free. Rachis not twisted. Longitudinal
ptyxis erect, horizontal ptyxis erect. Leaflets simple, with
numerous parallel veins and no distinct midrib, leaflets inserted
along the adaxial midline of the rhachis; leaflets lacking a distinct basal
callosity; epidermal cells elongated obliquely or transversely
to long axes of leaflets. Leaves pubescent, at least when young,
with branched or simple transparent trichomes.
Microsporophylls: spirally aggregated into determinate, sessile
male cones and each with a simple sterile apex, with a deflexed
broadly triangular termination. Each microsporophyll bearing numerous
microsporangia (pollen-sacs) on its abaxial surfaces. Microsporangia
opening by slits. Pollen cymbiform, monosulcate.
Megasporophylls: spirally aggregated into determinate, sessile
female cones. Sporophylls simple, appearing peltate with a simple
dilated apex or lamina with a deflexed broadly triangular apical termination.
Ovules two (rarely three), sessile, orthotropous, inserted on
the inner (axisfacing) surface of the thickened lamina and directed
inwards ("inverted").
Seeds: subglobular to oblong or ellipsoidal, with a red outer
sarcotesta. Endosperm haploid, derived from the female gametophyte.
Embryo straight; with 2 cotyledons that are usually united at
the tips and a very long, spirally twisted suspensor. Seeds radiospermic;
germination cryptocotular.
The Cycad Pages
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© 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
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