Statut biogéographique : Espèce signalée de Guyane française sur la base d'une collecte déterminée par M.T. Strong: Mamaribo, bord de route, 26/05/1989, M. Hoff 5573 (CAY041178 [Bulbostylis truncata (Nees) M.T.Strong 1993, det M.T. Strong, 2003]). A Cayenne deux autres collectes ont été identifiées comme tel (Trou Poisson, savane-roche, 15/05/2001, V. Hequet 1104, CAY25817 [B. cf. truncata, det. V. Hequet, 2001]; Anton, 04/06/2015, R. Girault & J. Sutra CAY213718 [B. truncata, det. R. Girault, 2015]).

Taxonomie : D'après M.T. Strong (1993): "Of the small South American annual species of Bulbostylis (those less than 30 cm high) with an umbellate-cymose inflorescence, B. truncata seems most closely related to B. capillaris (L.) Clarke and has been circumscribed by Pfeiffer (1924) and Uittien (1933) as a variety of that species. Bulbostylis truncata is similar to B. capillaris as well as in its annual life cycle, but differs in a number of significant characteristics. The summit of the leaf sheath of B. truncata is acute to sub-truncate, abruptly narrowing into the blade, and devoid of long apical fimbriae typical of most species of Bulbostylis, while the summit of the leaf sheath in B. capillaris narrows more gradually into the blade and has long apical fimbriae. Achenes of B. truncata are typically obovate, shallowly 3-lobed at the apex, with smooth, lighter-colored angles, and at maturity become dark brown to grayish-brown with low, translucent, shiny papillae. Achenes of B. capillaris are typically obovoid, unlobed at the apex, and at maturity uniformly light-brown, with a distinct transversely-rugulose surface."