Drynaria rigidula (a fern) - endangered species listing

NSW Scientific Committee - final determination



The Scientific Committee, established under the Threatened Species Conservation Act 1995, has made a Final Determination to listDrynaria rigidula (Sw.) Beddome, a fern, as an ENDANGERED SPECIES on Schedule 1, Part 1 of the Act and as a consequence omit reference to Drynaria rigidula (Sw.) Beddome as a species presumed extinct on Part 4 of Schedule 1 of the Act. Listing of endangered species is provided for by Part 2 of the Act.

The Scientific Committee has found that:

1.Drynaria rigidula was presumed extinct in New South Wales and has been recently rediscovered.

2. It is a fern (family Polypodiaceae) that grows on rocks or as an epiphyte from rainforests north from the Clarence River in northern coastal N.S.W. This species is described in the Flora of New South Wales (Volume 1, Harden 1990) as:

" Rhizome densely covered with long, reddish brown, ciliate scales. Both kinds of fronds covered, at least in part, with narrow ciliate scales and stellate hairs; the sterile ('nest') fronds long and narrow, 12-36 cm long and 6-8 cm wide, slightly lobed to pinnatifid; the fertile fronds pinnate, to 150 cm long including the stipe. Sori in regular rows on either side of the midvein of the pinnae. Creeping or clump-forming species found in rainforest, rare in N.S.W., north from the Clarence River."

3. The species is currently known from only 3 locations in N.S.W., although it is common in Queensland. Only one plant is known from each of the known locations in N.S.W. It is not known from any conservation reserves.

4. The species is threatened by loss of habitat and the risk of extinction is high due to very low population numbers.

5. In view of 1, 3 & 4 above the Scientific Committee is of the opinion that the species is likely to become extinct in nature in New South Wales unless the circumstances and factors threatening its survival cease to operate.

Proposed gazettal date: 4/9/98

Exhibition Period: 4/9/98 to 9/10/98


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Page last updated: 28 February 2011