Citation: Ising, Trans. R. Soc. S. Aust. 89:283, fig. 2 (1965).

Synonymy: Not Applicable

Common name: None

Description:
Annuals, with few to several branches from the base to 30 cm long, decumbent or erect, with a tap root, sparsely to densely covered with usually spreading hairs with a scarcely developed broad base particularly on the undersurface of the leaves; leaves alternate, rarely clustered, oblanceolate-spathulate, subpetiolate and scarcely sheathing at the base becoming widely spaced, sessile, oblanceolate, obovate, elliptic to lanceolate or rarely ovate higher up, 0.8-5 x 0.4-2 cm, obtuse.

Inflorescence terminal, with 1 rarely 2 scorpioid cymes, with pedicellate flowers more or less loosely arranged and widely spaced when fruiting, with leaf-like bracts; sepals scarcely connate, c. 2 mm long or to 4 mm when fruiting, with lobes lanceolate, bluntly acute, covered with fine forward-directed and more or less appressed hairs; corolla tubular, white, glabrous except for papillose saccate protrusions in the throat, 2.5-3 mm long; lobes oblong, c. 1 mm long, with an obtuse or rounded apex; stamens inserted below the throat of the corolla tube, with anthers almost sessile, elliptic-ovoid, c. 0.5 mm long, with a mucronate appendage; ovary 4-lobed, with a style inserted near the middle, c. 0.7 mm long, with a terminal capital stigma.

Mericarps ovoid, with the outer surface obliquely compressed but with a slightly spongy crest vertically along the middle as well as surrounded by a slightly spongy rim, with margins incurved and studded with more or less elongate spines barbed at the apex, with ovate scar of. attachment in the middle to the lower third and continued into a ventral ridge to the apex, smooth, pale-brown.

	Habit, half flower and mericarp in two views.
Image source: fig. 536C in Jessop J.P. & Toelken H.R. (Ed.) 1986. Flora of South Australia (4th edn).

Distribution:  usually associated with granite or porphyry rocks. S.Aust.: LE, GT, FR, EA, EP. Conservation status: native Flowering time: Aug. — Nov.

SA Distribution Map based on current data relating to specimens held in the State Herbarium of South Australia

Biology: A number of collections from near Port Augusta to near Minnipa are available of this most widespread species in the genus. The fruits show a considerable range of variation in the size and development of the spines.

Author: Not yet available