22. Mimosa tenuiflora (Willdenow 1806: 1088) Poiret (1810: 66)

Trees, branches glabrescent, aculeate. Nectary absent. Stipules caducous. Leaves bipinnate, paripinnate, 8–14– foliolate, leaflets opposite, oblong, venation actinodromous, translucid punctuation absent. Inflorescence spike, axillary. Flowers sessile, actinomorphic, diplostemonous; calyx gamosepalous, sepals 4, corolla gamopetalous, tubular, whitish, petals 4; androecium dialystaminous, homodinamous, anthers longitudinal; ovary superior, stipitate, pluriovulate. Fruit craspedium, stipitate, linear, plane-corrugate, margin straight, epicarp glabrous, brown. Seeds obovate, plane, coat brown, hilum basal.

Examined material:— BRAZIL. Paraíba: Maturéia, Pico do Jabre, 800 m elev., 02 December 2019, fl., Areliana Gomes 3158 (HACAM) .

Distribution and ecology:— The species has a wide distribution in the Brazilian semiarid region, associated with the phytogeographic domain of the Caatinga (Amorim et al., 2016; Souza et al., 2021).

Phenology:— Registered with flowers in December.

Taxonomic discussion:— Mimosa tenuiflora can be recognized, mainly, by the arboreous habit, aculeate, bipinnate leaves and inflorescence in spikes. A characteristic that distinguishes it from other Mimosa species in the studied area is the presence of a trunk with dark bark and in many cases it is common to have orbicular galls covered by glandular trichomes, being brown in the other representatives of the genus.