Dillwynia glaucula (a shrub) - endangered species listing
The Scientific Committee, established by the Threatened Species Conservation Act 1995, has made a Final Determination to list the shrub Dillwynia glaucula Jobson & P.H. Weston as an ENDANGERED SPECIES on Part 1 of Schedule 1 of that Act. Listing is provided for by Part 2 of the Act.
NSW Scientific Committee - final determination
The Scientific Committee has found that:
1. Dillwynia glaucula Jobson & P.H. Weston was described by Jobson & Weston 1998 [Jobson, P.C. & Weston, P.H. (1998) Dillwynia glaucula (Fabaceae: Mirbelieae), a new species from the Southern Tablelands, New South Wales, Telopea 8: 1 - 5].
2. Dillwynia glaucula is an erect shrub, 0.75 - 2.3 m high. It most closely resembles Dillwynia sericea, from which it differs in its completely glabrous calyx, leaves and new shoots and by the blue-green tinge of the leaves. A full description and illustration are provided in Jobson & Weston (1998).
3. "Erect shrub (0.2-) 0.75 - 2.3 m high; taproot present and lacking lignotuber; bark smooth, red-brown with conspicuous cream lenticels. Branches and branchlets smooth, red-brown and entirely glabrous. Leaves spreading to reflexed, rarely loosely appressed, linear, triquetrous, occasionally slightly twisted, glabrous, minutely colliculate, young leaves glaucous, becoming bluish-green to green with age; petiole c. 0.5 mm long; lamina with a longitudinal adaxial groove, 4 - 7 mm long, c. 0.5 mm wide, apex obtuse, often with an incurved tip; stipules absent. Inflorescences axillary, often in upper axils of stem, 1-flowered. Peduncles 2.0 - 2.5 mm long; bracts ovate to broad-ovate, 0.5 - 1.0 mm long, entire, cucullate, red-brown, ciliate with white hairs in upper portion of margin; bracteoles ovate, c. 1 mm long, entire, yellow to brown, ciliate with white, straight to crisped hairs on upper portion of margin, attached to pedicel 0.25 - 0.75 mm below calyx tube. Buds green with cucullate upper calyx lobes. Calyx 10-ribbed, green, 3.5 - 6.0 mm long; calyx tube turbinate; lobes shorter than tube, lower lobes broadly acute, upper lobes v-shaped notched, divergent, margins ciliate with white hairs. Standard with lamina reniform with a deep v-notch separating lobes and basal oblong claw; lamina 4.5 - 5.5 mm long, 9.0 - 11.0 mm wide; lobes obovate, yellow with narrow red band (crescent) above claw; claw yellow-green, 4.0 - 5.0 mm long, 2.0 mm wide. Wings narrow-obovate, partially obscuring keel, cucullate, obtuse, auriculate on lower margin near base and clawed, yellow, 6.0 - 7.0 mm long, 1.5 - 2.0 mm wide; claw 1.0 - 1.5 mm long, c. 0.75 mm wide. Keel longitudinally broad-ovate, cymbicate, acute, red, 4.0 - 5.0 mm long, 2.0 - 3.0 mm wide; upper margin papillate; claw c. 1 mm long. Stamens with filaments 2.0 - 4.0 mm long; anthers 0.5 - 0.75 mm long. Gynoecium c. 4 mm long; ovary white-pubescent, c. 1.5 mm long; stipe glabrous c. 0.5 mm long; style hooked, glabrous, c. 2 mm long; stigma capitate. Pod ovoid, turgid, red-brown, pubescent with white hairs chiefly towards apex, 4.0 - 5.5 mm long, 3.0 - 4.0 mm wide; petals caducous during late development of pod. Seeds ovoid, smooth, black to dark olive with dark brown spots; aril cream, c. 2 mm long."
4. Dillwynia glaucula is known from three areas - near Windellama, Michelago and Numeralla.
5. Most populations occur in dry sclerophyll woodland on exposed clay lenses. Aboveground plants are thought to be killed by fire. It is thought that less than 2500 individual plants exist and the majority of these are in the Windellama area. Only a small number of plants (less than 20) are known from the Michelago area, whilst from Numeralla it is recorded as scattered at the one known location.
6. No population occurs in a conservation reserve. Most populations occur in roadside reserves and might be threatened by road widening. Other threats include clearing, hobby farms, grazing and weed encroachment. At one locality, where only a single plant occurs, there is heavy grazing.
7. In view of 3, 4 & 5 above the Scientific Committee is of the opinion Dillwynia glaucula 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: 23/7/99
Exhibition period: 23/7/99 - 27/8/99