Pichia caribaea, a New Species of Yeast Occurring in Necrotic Tissue of Cacti in the Caribbean Area

We describe Pichia caribaea, a new species of yeast which is closely related to P. amethionina. P. caribaea, of which 92 strains were isolated, is heterothallic and occurs in nature in both the haploid state and the diploid state. It produces asci with four hat-shaped spores, which are gradually released upon maturity. P. caribaea occurs in rotting tissue of cereoid and opuntia cacti on various islands in the greater Caribbean area and on coastal land masses surrounding it. It resembles P. amethionina var. pachycereana in its assimilation pattern of carbon compounds but differs in its ability to ferment glucose strongly. The DNAs of P. caribaea and the two described varieties of P. amethionina show about 40% complementarity. The type strain of P. caribaea is strain UCD-FST 81-62 (= ATTC 76713 = CBS 7692).