Richardia brasiliensis

Mexican clover


Richardia brasiliensis

Gomes 1801

pronounced: rich-ARD-ee-uh bruh-zill-ee-EN-siss

(Rubiaceae — the gardenia family)


common names: Mexican clover, Brazil pusley, poaia branca

The species was named for an English physician, Richard Richardson, and brasiliensis refers to Brazil, the country of origin of the species. In Brazil the plant is known as poaia branca. This is an introduced species and sometimes an invasive weed in many countries, including Hawaii, Indonesia, Japan, Thailand and Australia. It is a weed of citrus groves in Florida. In Australia, it is a weed of gardens, roadsides and disturbed sites, in coastal districts north from Sydney. The plant photographed was growing as a weed in a roadside flower bed in Picnic Bay.

This is a prostrate to ascending annual herb that grows from a deep root, with stems up to 40 cm long. It is hispid. The stems are freely branched, and rarely root from lower nodes. They are flattened to subterete.

The opposite leaves are elliptic to ovate in shape, have a pointed to rounded tip, are rough-textured on both sides, and are up to about 6 cm in length. The leaf base is elongated and the petiole may be almost absent, or up to 1 cm long. The petioles of opposite leaves are connected by stipules that have become sheath-like. These sheaths have ascending hairs to about 5 mm long.

The inflorescence is a cluster of up to about 20 flowers, sometimes more, with white or occasionally rose-pink petals. The flowers typically have 2 pairs of short, broad leaves underneath, the uppermost pair usually smaller than, and at right angles to, the lower pair. The outer part of the flower typically consists of 6 narrow lobes, up to 3.5 mm in length, with hairy margins. The lobes are joined at the base, forming an infundibuliform tube up to 1.5 mm long. The petals are also united.

Each flower produces up to 3 nutlets about 3 mm by 2 mm in size, their outsides with short thick hairs.

The root is often a home to nematodes.

The larvae of Blue Moon butterfly Hypolimnas bolina feed on the plant.

In Brazil the plant is used medicinally as an antiemetic, and for treating diabetes.


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.


Photographs taken in Picnic Bay 2013, 2014
Page last updated 24th March 2019