The evolution of the laterophysic connection with a revised phylogeny and taxonomy of butterflyfishes (Teleostei: Chaetodontidae)

Abstract

AbstractThe higher‐level relationships of butterflyfishes were examined using 37 morphological characters. This analysis combines characters derived from a histological study describing variation in the morphology of the laterophysic connection (an association between the swim bladder and the lateral‐line canals) with previously described morphological characters. The phylogenetic analysis resulted in four equally parsimonious trees that only differed in the placement of two of the 11 chaetodontid genera (Amphichaetodon and Forcipiger). We compare our analysis with previous hypotheses, present a new taxonomy consistent with the proposed cladistic relationships, and diagnose Chaetodon with five unreversed synapomorphies, including the evolution of characters composing the laterophysic connection. A new character‐based diagnosis of Chaetodon is provided and species are allocated accordingly; Chaetodon now includes the former Parachaetodon ocellatus and excludes the former subgenera Prognathodes and Roa. The evolution of the laterophysic connection is examined by optimizing character‐state transformations on the new hypothesis of relationships.