Phylogenetic Evidence for Two New <i>Bouteloua</i> (Poaceae: Chloridoideae) Species in Mexico and Guatemala

Abstract— Bouteloua is the sole genus within the subtribe Boutelouinae and comprises 60 described species, with 52 to 55 of them present in Mexico and 25 to 27 species endemic to the country. The most recent phylogenetic study using plastid and nuclear markers proposed a new infrageneric classification for Bouteloua . Bouteloua section Buchloë includes eleven species, one of which is B. diversispicula . This species exhibits a broad geographic distribution, ranging from the southern United States through Mexico to Central America, and displays considerable morphological variation. In this study, we aimed to investigate the phylogenetic placement of individuals of B. diversispicula . Phylogenetic hypothesis using maximum likelihood analysis was conducted on 110 Bouteloua taxa, including seven new from Churumuco, Michoacán, using two plastid markers ( rpl32-trnL and rps16-trnK ) and nuclear ITS (internal transcribed spacer). Six of the Bouteloua samples from Churumuco were nested within the clade of B . sect. Buchloë . Based on our molecular results and morphological evidence, we describe two new species of Bouteloua.