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Isotropis juncea Turcz.
Slender Lamb Poison

Reference
Bull.Soc.Imp.Naturalistes Moscou 26 (1):251 (1853)
Conservation Code
Not threatened
Naturalised Status
Native to Western Australia
Name Status
Current

Prostrate to decumbent perennial, herb or shrub. Fl. yellow/orange & red, Sep to Oct. Sand, sandy clay. Winter-wet depressions, near salt lakes.

Grazyna Paczkowska, Descriptive Catalogue, 21 June 1996
Image

Scientific Description

Erect, shrub, spindly shrub (broom-like) or herb. Stems terete, not spiny, glabrous; pustules or glands absent. Leaves or phylloclades clearly present, simple, alternate, not continuous with stem, 25-40 mm long, 2-5 mm wide, glabrous, flat with flat margins; margins entire; tubercles absent; pustules or glands absent. Stipules present and persistent to older leaves. Pedicel present, 9-10 mm long, hairy. Bracteoles present and persistent, 1-1.2 mm long, glabrous, not striate. Calyx 6.3-8 mm long, not accrescent, hairy, with simple hairs, ribless; pustules or glands absent. Corolla 10.5-17 mm long, multicoloured, mostly yellow, red or orange, with some yellow, red or orange spots, streaks or blotches; claws absent; standard 10-14 mm long, glabrous, not auriculate, wings 9.6-13 mm long, not auriculate, keel 9.5-11 mm long, not beaked, not auriculate, glabrous. Stamens ten; anthers 1.3-1.4 mm long, at two different levels (filaments alternately long and short); filaments free (or united at the very base), 6-7.5 mm long. Ovary sessile or subsessile, hairy or glandular; style 10.5-13 mm long, hairy or glandular towards the base, not bearded, terete. Fruit dehiscent (a pod or follicle), sessile or subsessile, not constricted between the seeds, round in cross-section, not beaked. Flowers in September and October. Occurs in the Eremaean and South-West Botanical Province, in the Coolgardie, Geraldton Sandplains, Avon Wheatbelt, Jarrah Forest, Mallee and Swan Coastal Plain IBRA regions.

C. Hollister and K.R. Thiele, 24 October 2023

Distribution

IBRA Regions
Avon Wheatbelt, Coolgardie, Esperance Plains, Geraldton Sandplains, Jarrah Forest, Mallee, Swan Coastal Plain.
IBRA Subregions
Katanning, Lesueur Sandplain, Merredin, Northern Jarrah Forest, Perth, Recherche, Southern Cross, Western Mallee.
Local Government Areas (LGAs)
Beverley, Coorow, Corrigin, Dowerin, Dumbleyung, Esperance, Gingin, Gnowangerup, Goomalling, Kellerberrin, Merredin, Moora, Mount Marshall, Northam, Nungarin, Quairading, Tammin, Victoria Plains, Westonia, Wongan-Ballidu, Yilgarn.