Pilosocereus cristalinensis should not be regarded as conspecific with P. machrisii (Cereeae, Cactaceae)

Pilosocereus cristalinensis was initially briefly described and later expanded and illustrated by Braun & Esteves (1987). Since then, it has been compared to P. machrisii, from which it differs by a combination of morphological traits and geographic distribution. However, Zappi (1994), in her taxonomic revision of Pilosocereus in Brazil, synonymized P. cristalinensis with P. machrisii, a treatment that has been followed until now. Recent molecular studies, however, demonstrate that P. machrisii and P. cristalinensis are not closely related phylogenetically. Based on these results, as well as fieldwork and morphological analyses, we propose the recognition of P. cristalinensis as a species distinct from P. machrisii.