Pultenaea elusa - critically endangered species listing

The Scientific Committee, established by the Threatened Species Conservation Act, has made a Final Determination to list the shrub Pultenaea elusa (J.D. Briggs & Crisp) R.P.J. de Kok as a CRITICALLY ENDANGERED SPECIES in Part 1 of Schedule 1A of the Act, and as a consequence, to omit reference to Pultenaea parrisiae subsp. elusa J.D. Briggs & Crisp from Part 1 of Schedule 1 (Endangered species) of the Act. Listing of Critically Endangered species is provided for by Part 2 of the Act.

NSW Scientific Committee - final determination

The Scientific Committee has found that:

1. Pultenaea elusa (family Fabaceae) is described by de Kok and West (2004) as a: 'straggling shrub, branches up to 0.5 m long; branchlets sparsely to densely hairy, hairs appressed. Leaves alternate, 5-16 x 0.6-2 mm, ratio 5.5 - 12.5, linear, straight, widest point at or above the middle, smooth; apex acute, pungent, recurved; base attenuate to cuneate, midrib prominent only; upper leaf surface glabrous, lower leaf surface sparsely to moderately hairy; hairs appressed, grooved. Petioles not decurrent. Stipules 5-9 mm long, appressed. Inflorescences dense, determinate, the few inflorescence-subtending bracts forming a lax involucre, flower-subtending bracts scale-like, persistent. Pedicel 1-1.2 mm long. Calyx 4-4.5 mm long, moderately to strongly hairy; lobes all straight, upper lobes apex acute, lower lobes apex acuminate. Bracteoles 3-3.5 mm long, boat-shaped to linear, placed on the calyx tube. Standard 5.5-7 mm long, yellow to orange; wing 5-6 mm long, yellow to orange; keel 5-5.5 mm long, red to purple. Pods 4-4.5 mm long, ratio 1.6-1.8; seeds not seen'. Flowering of this species has been recorded in September and October (NSW NPWS 2001).

2. This species was first described by J. D. Briggs & M. Crisp (1994) as Pultenaea parrisiae subsp . elusa from a specimen collected in 1938. They found  P. parrisiae to be most closely related to  P. paleacea, and that the subspecies  elusa differed from subspecies  parrisiae in having shorter calyx lobes, shorter pedicels, and longer floral bracts which terminate in two lobes with conspicuously villous central awns (Briggs and Crisp 1994). The two subspecies were subsequently found to be sufficiently distinct to justify recognition at specific rank (de Kok & West 2004):  P. elusa and  P. parrisiae s.str.

3. Pultenaea elusa is endemic to NSW and has only been recorded twice. The two collections were made in successive months (September and October) in 1938 on private property, at Penrose and Wingello, on the Southern Tablelands by the same collector, W. F. Blakely (DECC Atlas of NSW Wildlife, NSW NPWS 2001).

4. Both collections of Pultenaea elusa record the habitat only as a 'swamp'. There are a number of swamps in the vicinity (e.g. Hanging Rock Swamp, Stingray Swamp). The vegetation of these swamps commonly comprises scattered trees with a heath / sedge understorey (NSW NPWS 2001).

5. Unsuccessful searches for Pultenaea elusa in the late 1980s and 1998 in suitable habitat around the Penrose and Wingello areas (J. Briggs and K. McDougall pers. comm.), suggest that the current population is small and may already be extinct. However, no data are available to estimate the number of mature individuals. The lack of recent records and a reduction in habitat area and quality suggest that the population of  P. elusa has undergone a very large reduction over a time frame appropriate to the life cycle of the species.

6. Pultenaea elusa has a very highly restricted geographic distribution. The two known locations are separated by less than 5km (Hogbin 2002, DECC Atlas of NSW Wildlife). If this species still exists, its area of occupancy is likely to be no greater than 8 km2, based on 2 x 2 km grid cells, the spatial scale of assessment recommended by IUCN (2008).

7. Clearing and/or draining of wetlands for development of pasture and plantations since the last records of Pultenaea elusa has resulted in the severe fragmentation of potential habitat and is likely to have reduced the overall population and geographic range of the species. 'Clearing of native vegetation' is listed as a Key Threatening Process under the  Threatened Species Conservation Act 1995.

8. Sand mining occurs in the vicinity of some swamps and may affect the hydrology of swamps (NSW NPWS 2001). 'Alteration to the natural flow regimes of rivers and streams and their floodplains and wetlands' is listed as a Key Threatening Process under the Threatened Species Conservation Act 1995.

9. Much of the remaining (potential) suitable swamp habitat in the Penrose - Wingello area is on land that is grazed by domesticated livestock.

10. Pultenaea elusa (J.D. Briggs & Crisp) R.P.J. de Kok is eligible to be listed as a Critically Endangered species as, in the opinion of the Scientific Committee, it is facing an extremely high risk of extinction in New South Wales in the immediate future as determined in accordance with the following criteria as prescribed by the  Threatened Species Conservation Regulation 2002:

Clause 14

The species has undergone, is observed, estimated, inferred or reasonably suspected to have undergone or is likely to undergo within a time frame appropriate to the life cycle and habitat characteristics of the taxon:

(a) a very large reduction in population size,

based on:

(d) an index of abundance appropriate to the taxon,

(e) geographic distribution, habitat quality or diversity, or genetic diversity.

Clause 15

The geographic distribution of the species is estimated or inferred to be:

(a) very highly restricted,

and:

(d) a projected or continuing decline is observed, estimated or inferred in:

(i) an index of abundance appropriate to the taxon,

(ii) geographic distribution, habitat quality or diversity, or genetic diversity.

(e) the following conditions apply: 

(i) the population or habitat is observed or inferred to be severely fragmented;

(ii) all or nearly all mature individuals are observed or inferred to occur within a small number of populations or locations.

Dr Richard Major
Chairperson
Scientific Committee

Proposed Gazettal date: 11/12/09
Exhibition period: 11/12/09 - 05/02/10

References:

Briggs JD, Crisp MD (1994) Pultenaea parrisiae (Fabaceae: Mirbelieae), a new species from south-eastern Australia.  Telopea 5, 647-655.

de Kok RPJ, West JG (2004) A revision of the genus Pultenaea (Fabaceae). 3. The eastern species with recurved leaves.  Australian Systematic Botany 17, 273-326.  

Hogbin P (2002) 'Review of the TSC Act Flora Schedules: Recommendations to the Scientific Committee. Final Summary Report Dec 2002.' NSW NPWS, Hurstvill, NSW.

IUCN (2008) 'Guidelines for using the IUCN Red List Categories and Criteria. Version 7.0./ (Standards and Petitions Working Group of the IUCN Species Survival Commission Biodiversity Assessments Sub-committee: Switzerland).

NSW National Parks and Wildlife Service (2001) 'Approved Recovery Plan for the 'lost' threatened flora of south-eastern NSW.' NSW NPWS, Hurstville, NSW.