A new species of Chusquea subg. Rettbergia (Poaceae: Bambusoideae: Bambuseae) from Bolivia and a range extension and revised description for C. yungasensis

Chusquea latispicula, the second species of Chusquea subg. Rettbergia to be confirmed from Bolivia, is here described, illustrated, and compared with C. yungasensis. The new species is distinguished primarily on spikelet characters, including spikelet length and number of nerves on the lemma, but mainly by its spikelet width of 4–5 mm, for which this species is named. The new species is known from only one collection and thus is considered endemic to Bolivia. Four additional collections of C. yungasensis have been recorded since its original description in 2014, representing a range extension into the department of Cochabamba, which is documented herein. The newer collections also provide the basis for an updated description of this species. A preliminary conservation status assessment for C. latispicula and a revised one for C. yungasensis are included.