|The Cycad Pages
- Cycas ophiolitica K.D. Hill, "Telopea 5(1): 190-191, fig. 7" (1992). H—NSW
- "TYPE: Australia, Queensland, Port Curtis District: 48.6 km S of Marlborough on Bruce Highway, K.D. Hill 4140 & L. Stanberg, 1 Oct 1991 (holo NSW; iso BRI, CANB, K, DNA)."[NSW][NSW]
From the Greek, ophis, ophios, serpent or snake, and lithos,
stone or rock, in combination `ophiolite' as used for the rock
serpentinite, referring to the main occurrence of this species
on serpentinite-derived soils.
Hill 1992, fig. 7.
The `core' form of this species is in cultivation (mostly as wild-collected
plants) as Cycas `Marlborough Blue'. Some of the intergrading material is
also cultivated as C. normanbyana, although the type of
the latter name belongs to C. media (which see).
Distinguished from other Australian species by the relatively
broad, crowded, keeled and more or less glaucous leaflets, the grey-
or white-tomentose petioles, the orange-floccose crown and cataphylls, and the
small seeds. Leaflets are generally narrower and more crowded than
those of both C. media and C. megacarpa, and ovules
are fewer in number than those of C. media. Leaves are
also more frequently (but not always) terminated by a spine rather
than a pair of leaflets (both C. media and C. megacarpa
show about equal development of terminal spine or leaflets). Pure
forms are quite blue in new growth, becoming dark green with age,
and have narrow, stiff leaflets. In these characters, C. ophiolitica
resembles both C. platyphylla and C. couttsiana.
It differs from the former in the somewhat longer and broader
leaflets on longer leaves with longer petioles and the lesser amount
of orange tomentum around the cataphylls, and from the latter
in lacking the persistent white trichomes and by the less keeled
Although grouped with series Cairnsianosae by most characters,
this species differs in having wider leaflets with an interrupted
lower hypodermis. These are characters present in C. media
which shows substantial intergradation with C. ophiolitica.
It is possible that these seemingly anomalous characters have arisen through
introgressive gene flow.
Distribution and habitat:
This species reaches its best development on red clays over serpentinites
in the region between Marlborough and Rockhampton. Substantial
intergradation occurs with C. media and C. megacarpa
respectively north and south of this region, and plants from throughout
the range may show characters of these taxa.
The habitat is poorly conserved (or unconserved), and the
species is also under significant commercial collecting pressure.
1997 IUCN Red List of Threatened Plants category V.
ROTAP category 2V-.
Stems arborescent, to 2(-7) m tall, 14-20 cm diam. at narrowest point.
Leaves deep green or grey-green (bluish wnen new), semiglossy, 95-140 cm long, strongly to moderately keeled (opposing leaflets inserted at 80-120° on rachis), with 170-220 leaflets, with white and orange tomentum shedding as leaf expands to persistent below; rachis usually terminated by a spine. Petiole 18-35 cm long, pubescent, spinescent or unarmed (rarely), for 0-80% of length. Basal leaflets not gradually reducing to spines.
Median leaflets simple, strongly discolorous, 140-240 mm long, 6-7.5 mm wide, inserted at 45-70° to rachis, decurrent for 1.5-3 mm, narrowed to 3.5-5 mm at base (to 55-80% of maximum width), 6-9 mm apart on rachis; median leaflets section flat, or slightly keeled; margins recurved; apex aristate, spinescent; midrib flat above, raised below.
Cataphylls linear, soft, densely floccose, persistent.
Pollen cones ovoid, orange, 17 cm long, 8 cm diam.; microsporophyll lamina firm, not dorsiventrally thickened, 32-40 mm long, 10-14 mm wide, fertile zone 22-26 mm long, sterile apex 10-15 mm long, deflexed, apical spine prominent, sharply upturned, 7-11 mm long.
Megasporophylls 18-30 cm long, brown-tomentose; ovules 2-6, glabrous; lamina lanceolate, 40-70 mm long, 12-30 mm wide, regularly dentate, with 22-36 pungent lateral spines 1-5 mm long, 1 mm wide, apical spine distinct from lateral spines, 8-20 mm long.
Seeds flattened-ovoid, 29-33 mm long, 28-32 mm wide; sarcotesta orange-brown, slightly pruinose, 2.5-3.5 mm thick; fibrous layer absent; sclerotesta smooth. Spongy endocarp absent.