Euphrasia arguta R. Br. - proposed vulnerable species listing

NSW Scientific Committee - preliminary determination

The Scientific Committee, established by the Threatened Species Conservation Act, has made a Preliminary Determination to support a proposal to list the herb Euphrasia arguta R. Br. as a VULNERABLE SPECIES in Part 1 of Schedule 2 of the Act, and as a consequence, to omit reference to Euphrasia arguta R. Br. from Part 4 of Schedule 1 (species presumed extinct) of the Act. Listing of Vulnerable species is provided for by Part 2 of the Act.

 

The Scientific Committee has found that:

 

1. Euphrasia arguta R. Br. (family Scrophulariaceae) is described by Barker (1992) as an "erect annual herb 20-35 cm high, branches densely hairy with recurved stiff non-glandular hairs. Upper stem leaves ovate to elliptic, often broadly so, 6-14 mm long, 3.5-13 mm wide, margins + deeply lobed, usually with 2-4 pairs of teeth. Racemes mostly 50-90-flowered. Calyx 5.5-7 mm long, usually scabrous. Corolla 10-14 mm long, white to lilac with yellow markings; tube 6.7-8.5 mm long, glabrous at base. Stamen filaments usually glabrous; anthers 0.9-1.7 mm long, connective hairy. Capsule 4-7.5 mm long, upper half bristly. Flowers October – January."

 

2. Euphrasia arguta R. Br. was recently rediscovered in the Nundle area of the NSW north western slopes and tablelands in 2008. Prior to this, it had not been collected for 100 years. Historically, Euphrasia arguta has only been recorded from relatively few places from an area extending from Sydney to Bathurst and north to Walcha, in the central coast, western slopes and tableland regions (Barker 1982; Barker 1987; Barker 1992; records from National Herbarium of NSW, Sydney).

 

3. The current known populations are located in the Nundle State Forest in eucalypt forest with a mixed grass and shrub understorey (D Binns pers. comm. February 2009). This area is located at the junction of the New England Tableland, NSW North Coast, and Nandewar Bioregions (sensu Thackway & Creswell 1995). Ecological information from historical herbarium records is scarce. Three collections noted the following habitat, 'in the open forest country around Bathurst in subhumid places', 'on the grassy country near Bathurst', 'in meadows near rivers' (Barker 1982; 1987).

 

4. There are currently three populations of Euphrasia arguta located in two areas approximately 14 km apart. The total number of mature individuals was not considered to be low following a survey in February 2009 (D. Binns unpublished data February 2009). The largest population contained an estimated 15 000 individuals. It occurs in an area that was cleared for a fire break in January 2007, and was subsequently left to regenerate. The plants were most dense in the open disturbed area, and along the roadside, indicating the species may be responding to the disturbance (D. Binns pers. comm. April 2009). Two further populations are located about 14 km to the south-east and are themselves separated by some 3 kms. One contained only 6 plants at the time of observation, and the other 1120 plants (D. Binns pers. comm. February 2009).

 

5. The number of Euphrasia arguta plants may vary over time depending on the season of the year, and if there has been recent disturbance at the site. E. arguta has an annual habit and has been observed to die off over the winter months. Active growth and flowering is between January and April (D. Binns pers. comm. April 2009). As there has been only one season of observations of the populations of E. arguta since its rediscovery, trends in plant numbers over time are unknown. If information becomes available indicating a decline in the species, a re-assessment of the status of Euphrasia arguta may be warranted.

 

6. The geographic distribution of Euphrasia arguta was estimated to be very highly restricted. The extent of occurrence, measured using a minimum convex polygon covering the known distribution, was estimated to be 26 km2 (Scott 2009). This figure may be considered as a minimum as it is likely more populations may be located following searches of similar habitat in the Nundle area (D. Binns pers. comm. February 2009). The area of occupancy was estimated to be 12 km2, based on a 2 x 2 km grid, the scale of assessment recommended by IUCN (2008).

 

7. There are no known occurrences of Euphrasia arguta in a conservation reserve. The majority of E. arguta plants are located in Nundle State Forest. A small part of the largest population of E. arguta is located on private land that is adjacent to the State Forest. The land is currently used for rough grazing by sheep or cattle (D. Binns pers. comm. June 2009). Logging is currently occurring in Nundle State Forest and is planned for the land in the vicinity of the largest of the E. arguta populations (D. Binns pers. comm. June 2009). Whilst the majority of the population will be excluded from logging, the effects of logging activities on the species are unknown. D. Binns (pers. comm. June 2009) notes that all sites where E. arguta is found, have been either logged in the last few decades, or appear to have regrown from past clearing. Road maintenance and clearing roadside vegetation for fire breaks may pose a threat to E. arguta. Whilst clearing for a fire break resulted in recent good germination of the species in the largest population, it may also be seen as a threat, if such clearing activities adversely affected the soil seedbank. The frequency, seasonality and extent of road maintenance, along with any associated herbicide application may influence the response of the species to disturbance.

 

8. Euphrasia arguta is threatened by environmental and demographic stochasticity due to its very highly restricted distribution and the presence of all individuals within a small number of locations. It is prone to the effects of human activities or stochastic events within a very short time period in an uncertain future, and is thus capable of becoming Endangered, Critically Endangered or even Extinct in a very short time period.

 

9. Euphrasia arguta R. Br. is not eligible to be listed as an Endangered or Critically Endangered species. Should evidence of continuing decline become apparent following monitoring of the populations, a reassessment of the conservation status of Euphrasia arguta may be required.

 

10. Euphrasia arguta R. Br. is eligible to be listed as a Vulnerable species as, in the opinion of the Scientific Committee, it is facing a high risk of extinction in New South Wales in the medium-term future as determined in accordance with the following criteria as prescribed by the Threatened Species Conservation Regulation 2002:

 

Clause 18

The geographic distribution of the species is observed, estimated or inferred to be very highly restricted such that it is prone to the effects of human activities or stochastic events within a very short time period.

 

 

Dr Richard Major

Chairperson

Scientific Committee

 

Proposed Gazettal date: 19/02/10

Exhibition period: 19/02/10 – 16/04/10

 

References:

 

Barker WR (1982) Taxonomic studies in Euphrasia L. (Scrophulariaceae). A revised infrageneric classification, and a revision of the genus in Australia. Journal of the Adelaide Botanic Gardens 5, 1-304.

 

Barker WR (1987) Taxonomic studies in Euphrasia L. (Scrophulariaceae). V. New and rediscovered taxa, typifications, and other notes on the genus in Australia. Journal of the Adelaide Botanic Gardens 10, 201-221.

 

Barker WR (1992) Euphrasia. In 'Flora of New South Wales Volume 3'. (Ed. GJ Harden) pp. 522-590. (University of NSW Press, Sydney).

 

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). (http://intranet.iucn.org/webfiles/doc/SSC/RedList/RedListGuidelines.pdf).

 

Scott J (2009) Additional information for Euphrasia arguta R.Br. (Serophulariaceae). A confidential report to the Scientific Committee (NSW Threatened Species Conservation Act (1995)).

 

Thackway R, Creswell ID (1995) An interim biogeographic regionalisation for Australia: a framework for setting priorities in the National Reserves System Cooperative Program. Version 4.0. ANCA, Canberra.

Page last updated: 28 February 2011