|Photo Ken Hill
|The Cycad Pages
- Cycas micholitzii Dyer, "Gard. Chron. 38: 142-144, figs 48-49" (1905).
- "TYPE: Vietnam, ""Annam"", Micholitz s.n. (holo K, 4 sheets)."
(1854-1932), who made the type collections. Micholitz was a plant and insect
collector who collected extensively in Asia and New Guinea, employed for many
years by English plant merchants Sander & Sons.
Ho & Duong 1960,
This remarkable species was described by English botanist
Sir William Thiselton-Dyer
in 1905. Material apparently collected by Micholitz in Annam (northern
Vietnam), came into possession of
Director of Singapore Botanic Gardens, in 1904. He proposed that it
should be the type of a new genus (in correspondence to Thiselton-Dyer).
Thiselton-Dyer received material of Micholitz's collections from
Sander & Sons
in 1905, and from Ridley (including botanical drawings by an artist on
Ridley's staff) at about the same time. He astutely recognized that
this species belonged with the genus Cycas, despite the unusual leaf.
He described it as a new species in 1905, noting the similarities with the
specimen he had earlier described as C. rumphii var. bifida
but not combining the two. Subsequent authors until now have combined the
two, although closer inspection in recent times has now shown them to be
distinct (see C. bifida).
Quite large numbers of plants were collected by Micholitz and imported
to England by Sander and Sons, and the species created considerable interest
in European horticultural circles
Male and female coning was documented at Kew (anon. 1910, Raffil 1912), but
most of the imported plants were apparently lost in the general decline in
interest in exotic ornamental horticulture that followed WW1. The Dublin
Botanic Gardens is the only collection known (in 1998) to still have a single
plant from these collections.
The most immediately striking feature of this species is the dichotomously
divided leaflets. However, this also occurs in several related taxa, and in
a horticultural form of C. revoluta that is popular in Japan. The
subterranean habit, the small, soft microsporangiate cones, the loose, freely
peeling sarcotesta lacking a fibrous layer and the verrucose sclerotesta are
also all features shared by related species (section Stangerioides).
Within this group of related species, C. micholitzii is distinguished
by the short leaves with dull, comparatively short and narrow leaflets that
are dichotomously divided very near to the base, and small pollen cones with
distinct short spines on the microsporophyll tips.
Distribution and habitat:
The Annam Highlands region of central Vietnam and eastern Laos, in low,
scrubby but fairly dense woodland with substantial seasonal (monsoon)
rainfall and additional year-round montane rainfall.
Virtually unknown from the time of Micholitz until the last few years, this
species has been severely reduced in numbers both by collecting and by
unrestrained agricultural and forestry development. The rarity combined with
the unusual habit make it a very highly sought plant by collectors. It is
still, however, frequent in many places, and not considered to be immediately
Cycas micholitzii was listed by the
1997 IUCN Red List of Threatened Plants as category E,
but this listing refers primarily to the Chinese occurrences now regarded
as C. bifida.
IUCN (1994) Red List status VU A2c.
|Photo Ken Hill
Stems acaulescent, 10-15 cm diam. at narrowest point; 2-6 leaves in crown.
Leaves bright green, semiglossy or dull, 110-240 cm long, moderately keeled (opposing leaflets inserted at 90-120° on rachis), with 18-56 leaflets, with white tomentum shedding as leaf expands; rachis consistently terminated by paired leaflets. Petiole 50-105 cm long (40-55% of total leaf), petiole glabrous, spinescent for 70-95% of length. Basal leaflets not gradually reducing to spines, 230-330 mm long.
Median leaflets dichotomously branched, strongly discolorous, 230-360 mm long, 11-19 mm wide, inserted at 60° to rachis, narrowed to 2-3 mm at base (to 10-20% of maximum width), 35-60 mm apart on rachis; median leaflets section flat; margins flat; apex softly acuminate, not spinescent; midrib raised above, flat below.
Cataphylls narrowly triangular, soft, pilose, 60-80 mm long, articulated.
Pollen cones narrowly ovoid or fusiform, yellow, 15-25 cm long, 3-5 cm diam.; microsporophyll lamina soft, not dorsiventrally thickened, 13-18 mm long, 7-11 mm wide, apical spine prominent or rudimentary, sharply upturned, 1-6 mm long.
Megasporophylls deeply pectinate.
Seeds ovoid; fibrous layer absent; sclerotesta verrucose. Spongy endocarp absent.