Subterranean Fishes of the World

6187

2021

Taxonomy

313-344

1

Abstract: The Microcambevinae are a catfish subfamily endemic to the Brazilian Atlantic Forest, comprising rare species with interstitial habits. Microcambevines have been classified in two genera, Listrura and Microcambeva, but the relationships among included intrageneric lineages are still poorly understood. The objectives of this study are to conduct a phylogenetic analysis integrating morphological characters and a multigene dataset, and to propose a classification better reflecting morphological diversity and phylogenetic relationships. Phylogenetic analyses combining 57 morphological characters and a 2563 bp molecular dataset generated similar phylogenetic trees with high support values for most clades, including the two genera and some intrageneric groups. Six morphologically distinctive infrageneric lineages, three in Listrura and three in Microcambeva, are classified as subgenera, as well as two new species are described. The morphological diversity here recorded integrated to available information about habitat indicate high level of divergent specialisation among lineages. The analyses indicate a series of convergent morphological traits between Listrura and other teleosts sharing a fossorial lifestyle, as well as specialised traits independently occurring within Listrura lineages. Similarly, a great diversity of morphological traits occurs convergently in Microcambeva lineages and other teleosts sharing psammophilic habits. This study shows that combining molecular and morphological data yields well-supported phylogenies, making possible to unambiguously diagnose clades and to establish evolutionary hypothesis on morphological evolution. Keywords: Atlantic Forest; fossorial lifestyle; molecular phylogeny; Neotropics; osteology; new subgenera; psammophily

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