First genetic data for the critically endangered Cuban endemic Zapata Rail Cyanolimnas cerverai, and the taxonomic implications

Abstract

The taxonomic affinity of the near-flightless Zapata Rail Cyanolimnas 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 (Nesotrochis sp.) or to the South American rail tribe Pardirallini, i.e., the genera Neocrex, Mustelirallus, and Pardirallus. While pronounced phenotypic convergence—and divergence—among rails have repeatedly proven morphology-based phylogenies unreliable, thus far no attempt to sequence DNA from the enigmatic Cyanolimnas has 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 that Cyanolimnas belongs in tribe Pardirallini as sister to genus Neocrex, from which it diverged about 6 million years ago. Their divergence from Mustelirallus was estimated at about 9 million years ago. Based on morphology and our mitochondrial phylogeny, we conclude that it is unjustified to retain the monotypic genus Cyanolimnas and tentatively recommend that C. cerverai and the two Neocrex species are ascribed to genus Mustelirallus.

Sixty-fourth Supplement to the American Ornithological Society’s Check-list of North American Birds

“…Under the heading Family RALLIDAE: Rails, Gallinules, and Coots, add the following to the existing Notes: Linear sequence of Pardirallus and Mustelirallus follows Kirchman et al (2021) and Brown et al (2022). Notes.-Rufirallus schomburgkii was formerly placed in Micropygia, but genetic data (Kirchman et al 2021, Depino et al 2023 show that this species is sister to Rufirallus viridis (Müller, 1776) [Russet-crowned Crake].…”

“…3 . [p. 135] Phylogenetic analyses of nuclear and mitochondrial DNA sequences have shown that the genera Neocrex and Cyanolimnas are very closely related to extralimital species Mustelirallus albicollis (Garcia-R et al 2014, 2021; Kirchman et al 2021; Brown et al 2022). These findings result in the following changes:…”

“…Notes .—Formerly placed in the genus Cyanolimnas , but genetic data indicate that M. cerverai is closely related to and should be considered congeneric with Mustelirallus albicollis (Vieillot, 1819) [Ash-throated Crake] (Brown et al 2022). Similarities in phenotype (e.g., red-orange legs and base of the bill) are also apparent in the species formerly in Cyanolimnas and Neocrex and now placed in Mustelirallus .…”

“…Under the heading Family RALLIDAE : Rails, Gallinules, and Coots, add the following to the existing Notes: Linear sequence of Pardirallus and Mustelirallus follows Kirchman et al (2021) and Brown et al (2022).…”

Evolutionary history of New World crakes (Aves: Rallidae) with emphasis on the tribe Laterallini

“…On the other hand, representatives of Amaurolimnas and Mustelirallus crakes were placed together with the Aramides wood rails and Pardirallus rails in the ‘ Aramides ’ clade (sensu Garcia‐R et al, 2014a) or tribe Pardirallini (sensu Kirchman et al, 2021, 2022). Additionally, new results from historic DNA indicate that the Zapata Rail ( Cyanolimnas cerverai ) belongs to this ‘ Aramides ’ clade or tribe Pardirallini, closely related to Mustelirallus crakes (Brown et al, 2022). Another species, the Sora ( Porzana carolina ), formerly called Sora Crake, belongs to a clade with coots and moorhens (the ‘ Fulica ’ clade, sensu Garcia‐R et al, 2014a, 2020; tribe Fulicini, sensu Kirchman et al, 2021).…”