Mimosa orthocarpa Spruce ex Benth

Margoth Atahuachi, M. Leontien Van Der Bent, John R. I. Wood, Gwilym P. Lewis & Colin E. Hughes, 2016, Bolivian Mimosa (Leguminosae, Mimosoideae): three new species and a species checklist, Phytotaxa 260 (3), pp. 201-222 : 216

32. * Mimosa orthocarpa Spruce ex Benth

The occurrence of Mimosa orthocarpa in Bolivia represents a surprisingly large range extension for a species previously unrecorded from south of the Amazon and known to Barneby (1991) from the Amazon, northern South America and parts of Central America. Several collections (J.R.I. Wood et al. 22861, LPB, K, USZ, J.R.I. Wood & D. Soto 27134, LPB, K, USZ and D. Villarroel et al. 2046, USZ) from two disjunct localities in Bolivia—ca. 50 km S of Concepcion (Las Trancas and El Encanto), and Cerro Mutún, German Busch—can be attributed here. Mimosa orthocarpa is characteristic of granite rock platforms, particularly in the Lomerio area, a habitat also mentioned by Barneby (1991) in his notes on this species from northern South America. The species is morphologically close to and easily confused with M. tobatiensis Barneby & Fortunato, another species here newly documented for Bolivia (see below). These two species, distinguished by details of leaflet venation, indumentum, and pod shape (M. orthocarpa with larger, more robust and almost linear pods cf. the slightly falcate chartaceous pods of M. tobatiensis) and previously considered to be remotely allopatric putative sister species ( Barneby 1991), are thus now known to co-occur in Bolivia.