First genetic data for the Critically Endangered Cuban endemic Zapata RailCyanolimnas cerverai, and the taxonomic implications

Abstract

ABSTRACTThe taxonomic affinity of the near-flightless Zapata RailCyanolimnas cerverai, a Critically Endangered and highly localized species endemic to Cuba, has long been debated. Morphological analyses have suggested that this species, which constitutes a monotypic genus, could be related either to the extinct Tahitian Cave Rails (Nesotrochissp.) or to the South American rail tribe Pardirallini, i.e., the generaNeocrex, Mustelirallus, andPardirallus. Whilst pronounced phenotypic convergence–and divergence–among rails have repeatedly proven morphology-based phylogenies unreliable, thus far no attempt to sequence DNA from the enigmaticCyanolimnashas succeeded. In this study, we extracted historic DNA from a museum specimen collected in 1927 and sequenced multiple short fragments that allowed us to assemble a partial sequence of the mitochondrial cytochrome oxidase I gene. Phylogenetic analyses confirm thatCyanolimnasbelongs in tribe Pardirallini as sister to genusNeocrex, from which it diverged about six million years ago. Their divergence fromMusteliralluswas estimated at about eight million years ago. Based on morphology and our mitochondrial phylogeny, we conclude that it is unjustified to retain the monotypic genusCyanolimnasand tentatively recommend thatC. cerveraiand the twoNeocrexspecies are ascribed to genusMustelirallus.Abstract Figure