Ancestral biogeography and ecology of marine angelfishes (F: Pomacanthidae)

Abstract

Marine angelfishes (F: Pomacanthidae) are amongst the most conspicuous reef fish families inhabiting reefs on tropical and subtropical latitudes. While being disproportionately represented in the marine ornamental fish trade, only a handful of taxonomically restricted studies explored their biogeographic history and the evolution body size and trophic guilds. Here, we reconstruct the phylogenetic history for 70 pomacanthid species (85% of nominal species), based on previously published data for three nuclear and four mitochondrial markers. We use the resulting phylogenetic framework to explore the ancestral biogeography and ecological diversification of the family. Divergence times and ancestral range estimation highlight the origins of the family most likely lie in the Central Pacific region. Vicariance among ocean basins reflects the impact of the Terminal Tethyan Event and the closure of the Isthmus of Panama in the historical biogeography of Pomacanthus and Holacanthus genera. The reconstruction also uncovers ancestral colonization pathways via the Pacific Ocean into the western Atlantic waters for Holacanthus. We confirm the Indian Ocean invasion scenario previously proposed for the “acanthops” complex (genus: Centropyge). Finally, interspecific variation in body size among clades appeared to be correlated to some degree with trophic guilds, whereby 15% of variance in body size was explained by trophic modes. This suggests that the higher ecological diversification observed in the Centropyge clade might be promoted by smaller body sizes acting as an ecological novelty allowing the expansion of the genus within available niches.