Genoplesium vernale (a terrestrial orchid) - vulnerable species listing
The Scientific Committee, established by the Threatened Species Conservation Act, has made a Final Determination to list the terrestrial orchid Genoplesium vernale D. L. Jones as a VULNERABLE SPECIES on Schedule 2 of that Act. Listing of Vulnerable Species is provided for by Part 2 of the Act. The Scientific Committee previously made a Preliminary Determination for this species under the name of Genoplesium vernalis.
NSW Scientific Committee - final determination
The Scientific Committee has found that:
1. Genoplesium vernale (Orchidaceae) is a newly described terrestrial orchid species (D. L. Jones, 2001, Six new species and a new combination in Genoplesium (Orchidaceae) from eastern Australia. The Orchadian (2001) Vol. 13, No. 7 pp. 293-307. G. vernale is described as: Terrestrial tuberous herb. Leaf 10-18 cm long, 0.15-0.3 cm wide, terete, dark green, reddish at the base; lamina closely sheathing throughout, 10-15 mm long, 2-3 mm wide, oblanceolate-subulate, ending 5-20 mm below the first flower. Inflorescence 15-25 cm tall, bearing 10-25 flowers in a densely crowded spike 2-4 cm long. Flowers 3.5-4.5 mm diam., dark purplish black, porrect to semi-nodding; lateral sepals obliquely erect. Ovary linear-obovoid, to c. 2.6 mm long, slightly curved, green. Dorsal sepal cucullate, broadly ovate when flattened, 3-3.5 mm long, 2-2.3 mm wide, concave; margins with minute glandular cilia, apex acuminate. Lateral sepals nearly parallel, narrowly oblong-lanceolate, 4-4.5 mm long, 1.2-1.3 mm wide, base gibbous, margins entire, distal margins involute, apex narrowly and bluntly acute, sometimes a vestigial gland present. Petals porrect to spreading, narrowly ovate-lanceolate, c. 3 mm long, c. 12 mm wide, margins with minute glandular cilia, apex long-acuminate. Labellum attached by a short claw to the apex of the column foot; lamina narrowly oblong-elliptic, 2.5-2.8 mm long, 1.2-1.5 mm wide, shallowly curved throughout, suddenly contracted to an apiculate apex, externally papillate, margins denticulate, distal margins slightly irregular, with minute glandular cilia. Callus extending nearly to the labellum apex, occupying most of the ventral surface of the lamina, oblong, sometimes constricted above the middle, fleshy, dark purple to brownish black, base yellow, surface colluviate, apex entire. Column c. 2 mm long, c. 1.8 mm wide. Wings lobed about halfway to the base, the lobes not divergent; posterior lobe linear, whitish, obtuse; anterior lobe ovate-lanceolate, dark red, acute, the margins irregularly denticulate. Anther c. 0.8 mm long, with a linear to filiform rostrum about 0.3 mm long. Stigma broadly elliptic, c. 0.5 mm long, c. 0.5 mm wide. Pollinarium c. 1 mm long; pollinia c. 0.8 mm long, yellow, granular, caudicle ligulate, c. 0.15 mm long; viscidium c. 0.2 mm wide. Capsules erect, narrowly obovoid, 4-5 mm long, c. 0.3 mm wide.
2. Genoplesium vernale is restricted to a narrow geographic range from near Mogo to west of Ulladulla. It occurs in dry sclerophyll forest.
3. Recent surveys during 2000 have found the species at some 28 locations, although several of these are only separated by distances of less than 300 m. The number of populations known is likely to be less than 20. The abundance, above ground, at known sites is small and ranges from 1 to 139. Sites are known from the following NPWS reserves: Budawang National Park, Morton National Park and Murramarang National Park.
4. Threats to the species are generally localised and include construction and maintenance of roads, forestry tracks and utility easements. There has been some clearing of habitat in the past and at a number of sites future logging may be a threat. Populations may also be at risk due to the small numbers of plants. This predisposes the species to declines via stochastic events.
5. In view of 2, 3 and 4 above the Scientific Committee is of the opinion that Genoplesium vernale is likely to become endangered unless the circumstances and factors threatening its survival or evolutionary development cease to operate, and is therefore eligible for listing as a vulnerable species.
Proposed Gazettal date: 05/10/01
Exhibition period: 05/10/01