Mimosa pigra var. pigra

Tilcayo Cats original · Plants · Sources and editorial assessment · Originals retention rule

Mimosa pigra var. pigra is a variety of Mimosa pigra, a prickly plant in the pea family, Fabaceae. It is native to Mexico, Central America, the Caribbean and much of South America; Kew also lists Florida within its native range. The name Acacia rubiginosa Colla, published in 1834, is now treated as a synonym of this variety.

Identification

The leaves divide into paired branches, each with many small leaflets. Isely's 1973 identification key distinguishes variety pigra by its numerous prickles on the stems and leaf stalks and the dense hair covering that conceals the surfaces of its pods before maturity. That key contrasts it with the less prickly variety berlandieri.

A flora of Brazil's Espírito Santo state describes locally collected plants of variety pigra as upright and about one metre tall, with densely hairy branches and narrow leaflets. Its account of the species describes small flower heads with pinkish stamens.

The same flora distinguishes variety pigra from dehiscens by the fruit segments: in pigra the partition is hard and resistant, and the densely bristly segments remain closed. The measurements and growth form in that treatment describe regional material, rather than the full range of variation.

Distribution and records

Kew records introductions across much of tropical Africa, parts of Asia and northern Australia. In Espírito Santo, the variety was recorded in dense moist forest at approximately 1,000 metres elevation.

A herbarium specimen collected near Ladyville, Belize, in 1996 documents a woody plant with stems reaching about three metres on a dry roadside with sandy soil and rocky limestone. This provides a specific locality and habitat observation, rather than a general description of every population.