|The Cycad Pages
- Macrozamia cardiacensis P.I. Forst. & D.L. Jones, Fl. Australia 48: 717 (1998). H—BRI
- "TYPE: Australia, Queensland, Cardiac Hill. Mt Walsh National Park, 26 Feb. 1993, P.I. Forster 13109A & P. Machin (holo BRI)."
In reference to the occurrence on a precipitous site known locally as Cardiac Hill.
A member of the M. miquelii complex, separated by its large
stature, usually darker green leaves with spines for only up to
two-thirds of the petiole length, and the large size of the male and
female cones. Allied to M. douglasii, from which it differs in
the pale yellow callous bases of the leaflets, the proximal leaflets
being more closely spaced (20-28 mm apart), and the greater number of
reduced spine-like leaflets on the petiole (18-30).
Distribution and habitat:
Endemic in south-eastern Queensland, where it is restricted to Mt Walsh
National Park. Plants form extensive colonies on precipitous slopes in
open forest dominated by Eucalyptus acmenoides and E.
major. M. cardiacensis is restricted in its known occurrence,
but is very common at the two known localities, both in Mt Walsh
M. cardiacensis is restricted in its known occurrence, but is very common at the two known localities, both of which are conserved in Mt Walsh National Park (IUCN Red List category LR,lc; ROTAP category 2RC-t).
Plants acaulescent or arborescent (less commonly), stem 0-0.4 m tall,
20-40 cm diam.
Leaves 10-20 in crown, deep green, highly glossy, 150-200 cm long,
flat (not keeled) in section, with 100-140 leaflets; rachis not spirally
twisted, straight, lax and pendulous; petiole 30-40 cm long, straight,
spinescent, 13-20 mm wide at lowest leaflets; basal leaflets reducing to spines.
Leaflets simple, strongly discolorous; margins flat; apex entire,
spinescent; median leaflets 230-310 mm long, 9-11 mm wide.
Pollen cones fusiform, 35-40 cm long, 6.5-8 cm diam.; microsporophyll
lamina 22-32 mm long, 10-15 mm wide; apical spine 2-30 mm long.
Seed cones narrowly ovoid, 32-36 cm long, 11-14 cm diam.;
megasporophyll lamina 35 mm long, megasporophyll with an expanded peltate apex
45 mm wide, 25 mm high; apical spine 7-48 mm long.
Seeds oblong, 22-35 mm long, 12-20 mm wide; sarcotesta orange to red.