Chamaecrista mimosoides

fishbone cassia

 

Chamaecrista mimosoides

(L.) Greene 1899

pronounced: kam-eye-KRISS-tuh mim-oh-SOY-deez

(Fabaceae — the hibiscus family)

synonym — Cassia mimosoides

L. 1753

pronounced: KASS-ee-uh mim-oh-SOY-deez

synonym — Cassia sensitiva

Roxb. 1814

pronounced: KASS-ee-uh senz-it-EYE-vuh

common names: fishbone cassia, feather-leafed cassia

Chamæcrista is derived from two Latin words, chamæ-, ground, and crista, a tuft, crest; mimosoides means ‘like Mimosa’, referring to the finely divided pinnate leaves.

This is an annual or short-lived perennial herb, which is sometimes prostrate, but more usually an erect subshrub growing to a height of about 1.2 m. It is found on forest margins, woodlands, grasslands, disturbed sites, and by the roadside, usually at altitudes of 300 – 2000 m. As well as in Australia, it is found in the drier areas of tropical Asia and tropical Africa. It grows well in poor and dry soils, and is very drought-resistant. Its Australian distribution is across northern Australia, down the Queensland coast, and into northern NSW. The photographs were taken in Picnic Bay, by the bushland track behind the local museum.

There is a tap root, and the stems sometimes become woody above ground level. The stems are variable, usually puberulent with short curved hairs, but sometimes more-or-less clothed with longer spreading hairs.

The leaves are compound, linear to linear-oblong, more-or-less parallel-sided, up to about 10 cm long and 1.5 cm wide, with 16 – 76 pairs of oblong leaflets, that are small, asymmetric and blunt at the apex. This makes the leaf appear like a fishbone, hence one of the common names. The petioles always bear a gland below the bottom pair of leaflets. The leaves react to touch in much the same way as those of the Sensitive Plant, Mimosa pudica.

The inflorescence is solitary and axillary, with one to three flowers, on slender pedicels about 1 cm long The flowers are yellow, have 5 petals, and are of the typical cassia form. The petals are obovate, 4 – 13 mm long, 2 – 9 mm wide. There are 10 stamens, alternately long and short. The ovary has stiff, appressed hairs, and the stigma is flat.

The seed pods are linear to linear-oblong, usually 3.5 – 8 cm long (but sometimes shorter) and about 5 mm wide, containing 12 – 24 seeds that are flat and smooth.

As a legume, with nodulating roots fixing atmospheric nitrogen, the plant is sometimes used for soil improvement, including use as a green manure.

It is also used medically, the roots being used in the treatment of dysentery and stomach pains.

Fishbone cassia is cultivated in Japan, where a tea is made from it. In some countries the leaves are cooked and eaten as a vegetable.

It is a food plant for the larvae of Eurema desjardinsii (the angled grass yellow butterfly, found in Africa) and Eurema hecabe (the common grass yellow of Asia, Africa and Australia).

 

Information about medicinal qualities of plants, or about their use as medicines, is for interest only, and is not intended to be used as a guide for the treatment of medical conditions.

 

Photographed in Picnic Bay 2019
Page last updated 16th April 2019