Taxonomic revision of the flatfish genera Zebrias Jordan and Snyder, 1900 and Pseudaesopia Chabanaud, 1934 with notes on Aesopia Kaup, 1858 (Pleuronectiformes: Soleidae)

Abstract

The taxonomic status of the 25 nominal species of the Indo-Pacific flatfish genus Zebrias (Pleuronectiformes: Soleidae) was revised based on a morphological study of 531 specimens, including 36 type specimens. Two distinct, monophyletic groups were identified differing in the confluence and attachment of the caudal fin to adjacent dorsal and anal fins. Species most closely associated to the type species Pleuronectes zebra were included in the genus Zebrias while the remaining species were assigned to the genus Pseudaesopia to accommodate Zebrias species having a shallowly confluent caudal fin with adjacent fins, among other characters. Ten species are now recognized and re-described in Zebrias while six species are recognized and redescribed in Pseudaesopia. Comprehensive generic definitions and identification keys to species are provided. In addition, the closely related and monospecific genus Aesopia is briefly discussed. Finally, potentially useful characters for a future phylogenetic study are discussed.