Macrozamia humilis (a perennial cycad) - endangered species listing

The Scientific Committee, established by the Threatened Species Conservation Act, has made a Final Determination to list the perennial cycad Macrozamia humilis D.L. Jones as an ENDANGERED SPECIES in Part 1 of Schedule 1 of the Act. Listing of endangered species is provided for by Part 2 of the Act.

NSW Scientific Committee - final determination

The Scientific Committee has found that:

1. Macrozamia humilis (family Zamiaceae) is described in Flora of Australia, Volume 48, 1992 (page 659) as: Plants acaulescent; stem 18-28 cm diam.; 2-7 leaves in crown. Leaves 35-65 cm long, moderately keeled, with 60-90 pinnae, mid- to dark green or grey-green, dull to semi-glossy; petiole 9-16 cm long, 6-8 mm wide at lowest pinna; rachis not to moderately spirally twisted. Basal pinnae not reducing to spines. Median pinnae simple or, rarely, dichotomously branched, 10-18 cm long, 4-7 mm wide (ultimate segments 2-3 mm wide), distinctly discolorous; margins flat; apex entire, not spinescent. Pollen cones fusiform, 14-19 cm long, 4.5-5.5 cm diam.; microsporophyll lamina 14-20 mm long, 11-18 mm wide; apical spine 1-10 mm long. Seed cones ovoid, 10-15 cm long, 6-8 cm diam.; megasporophyll with an expanded, peltate apex 40-50 mm wide and 15-20 mm long; apical spine 2-25 mm long. Seeds ovoid, 25-31 mm long, 22-26 mm wide; sarcotesta red.

2. The species is part of the M. heteroma complex and is endemic to NSW. The species is known only from Inverell.

3. Macrozamia humilis is known from a single location where it occurs on an isolated outcrop of laterite capped granite. The majority of the population in this location is within a Department of Infrastructure, Planning and Natural Resources reserve managed for public recreation. Management objectives at the reserve include flora management.

4. There has been a historical decline in the amount of available habitat for the species. Macrozamia humilis is further threatened due to small population size and continued clearing.

In view of the above the Scientific Committee is of the opinion that Macrozamia humilis D.L. Jones is likely to become extinct in nature in New South Wales unless the circumstances and factors threatening its survival or evolutionary development cease to operate.

Proposed Gazettal date: 13/12/02
Exhibition period: 13/12/02 - 31/01/03