Cassia brewsteri

Family

Caesalpiniaceae

Botanical Name

Cassia brewsteri (F.Muell.) Benth.

Bentham, G. (1864) Flora Australiensis 2: 282. Type: ?.

Synonyms

Cathartocarpus brewsteri F.Muell., Fragmenta Phytographiae Australiae 1(5): 110(1859), Type: Banks of the Burdekin River..

Common name

Cassia pea; Leichhardt Bean

Stem

Tree to 30 m tall.

Leaves

Stipules falling early. Lower leaflets smaller than upper leaflets on same leaf; 4 or 6 per leaf. Leaflets 3.2-6.5 x 1.5-3 cm; oblong-elliptic, apex retuse.. Undersurface whitish-green. Leaflets petiole grooved on the upper surface, 3-4 mm long. Lateral veins looping. Compound leaf petiole swollen at its junction with the twig.

Flowers

Inflorescence terminal, 7-20 cm long, 10-50 flowers, pendulous. Flowers 10-18 mm diam. Calyx hairy on outside, 5-6 mm long, obtuse. Petals 5, glabrous, ovate, 7 x 5 mm. Stamens either 10 in total without staminodes present, or 7 with 3 staminodes. Stamens in 3 shapes and sizes: a) 3 with filament elongated, 13-14 mm long, S-curved with a fleshy bulbous node near the centre, anthers opening in apical pores with both basal and terminal apertures; b) 4 stamens alternating with previous type, shorter, 8 mm long with basal pores on anthers, anthers 3 x 1 mm; c) 3 stamens reduced to staminodes, filament 6 mm, anther 1 x 0.4 mm. Style long, longitudinally ribbed or 4-angled, 16-18 mm long, bristles on style towards base.

Fruit

Pods to 45 cm, moniliform, somewhat comprssed or +/- circular in transverse section. Fruit may be purplish with glaucous bloom. Seed 11 x 8 mm, covered in leathery coat, greyish brown in colour.

Seedlings

Cotyledon oblong or elliptic, 13-16 x 5-8 mm, thickened. Cotyledons 3-veined or lateral veins indistinct. First pair of true leaves compund, alternate or opposite with 2-4 opposite leaflets. Hypocotyl hairy and flattened. 10-th leaf seedlings with stipules triangular 0.5 mm long; usually with 4 leaflets; a few scattered small hairs may be visible with a lens on underside of the leaflets; stem has a few scattered short hairs visible with a lens; young twigs and petioles often pinkish or red.

Distribution and Ecology

Occurs in inland NEQ, down to SE Queensland. Altitudinal range from about 90 to 640 m. Mainly grows in open forest and woodland but also occurs in vine thickets.