It is known from Baja California as far south as Morelos and as far east as San Luis Potosí, as well as from Arizona and New Mexico.

Stems are white and covered with a velvety pubescence when young, armed with curved prickles about 6 mm (0.25 inches) long.

Leaves trifoliate, leaflets stiff and leathery, generally broader than long.

Flowers are crowded in terminal racemes, bright scarlet, about 4 cm (1.6 inches) long.

[5][6][7][8] The seed walls are potentially lethal if consumed due to the alkaloids contained in them.