Otatea colombiana (Poaceae: Bambusoideae: Bambuseae: Guaduinae), a New Species Endemic to Colombia

Otatea is one of the five genera recognized in Guaduinae, a Neotropical subtribe belonging to tribe Bambuseae (tropical woody bamboos) and subfamily Bambusoideae (Poaceae). Otatea currently has 11 described species, all of which are adapted to dry habitats, and all of which are present inMexico. Only Otatea fimbriata is reported forMexico, Central America, and Colombia. A previous phylogenetic analysis demonstrated that the only Colombian population of O. fimbriata (located in Norte de Santander) was closely related to the rest of this widespread species. However, further morphological evidence from the recent flowering of cultivated plants from the wild Colombian population allowed its unambiguous separation from the rest of the populations of O. fimbriata. The Colombian population differs from O. fimbriata in having short and few oral setae on the culm leaves, longer spikelets with five to seven florets per spikelet, and longer glumes, lemmas, and paleas. This new evidence therefore leads us to propose a new species endemic to Colombia; in this manuscript, we describe and illustrate O. colombiana and compare it with its closely related species, O. fimbriata. Only a single locality, located in a non-protected area, is known for O. colombiana with the single population consisting of a few hundred plants. Thus we suggest that if a Red List evaluation of this species were performed, it would be assigned to the Critically Endangered category, following the categories and criteria of the International Union of Conservation of Nature's Red List.