Yucca carrii (Asparagaceae), a New Species from the Northern Gulf Coast Prairie of Texas

Abstract

Yucca carrii, a new species from the northern Gulf Coastal Prairie of Texas is described. Morphology indicates that Yucca carrii belongs to Section Chaenocarpa (the dry-fruited yuccas). A lack of observed fruit production to date and reduced pollen viability indicates that this species may be of hybrid origin. The sole pollinator, the yucca moth, has not been documented within the species' range; it may be extirpated. Although known from few populations, the wide-ranging distribution of this species along the north Texas coast, ecological niche specificity and morphological distinctiveness indicates this taxon may have a long history in the area and persists by way of vegetative reproduction. It may be vulnerable to extinction and conservation measures are warranted. DNA analyses are needed to determine the origin and relationship of Y. carrii within Yucca L. Examination of the type of Y. tenuistyla Trel. revealed Y. tenuistyla is a nomen confusum that was described from a mixed collection of three yucca species, none of which is Y. carrii.