Revision of the genus Lepidopsetta Gill, 1862 (Teleostei: Pleuronectidae) based on larval and adult morphology, with a description of a new species from the North Pacific Ocean and Bering Sea

The endemic North Pacific pleuronectid genus Lepidopsetta Gill is revised to include three species: L. bilineata (Ayres), L. polyxystra n. sp., and L, mochigarei Snyder. Adults of L. bilineata can be distinguished by a low gill-raker count and high supraorbital pore count, larvae may be distinguished by four dorsal midline melanophores, heavy finfold pigment, a short snout-to-anus length, and a deep body. The species ranges from Baja California to the eastern Aleutian Islands and the extreme southeastern Bering Sea. Adults of L, mochigarci are distinguished from all other members of Lepidopsetta by higher scale and preopercular pore counts and lower gill-raker and supraorbital pore counts. Larvae are similar to larvae oft. bilineata but can be distinguished by their postanal pigment pattern and melanophores on pectoral-fin rays. Lepidopsetta mochigarei ranges from the southern Sea of Okhotsk to Korea. Adults of L. polyxystra n. sp. are diagnosed by a high gill-raker count and low supraorbital pore count; larvae are diagnosed by two dorsal midline melanophores, light finfold pigment, long snout-to-anus length, and a slender body. The species is found from Puget Sound through the Bering Sea and Aleutian Islands to the Kuril Islands, overlapping with L. bilineata from the extreme southeastern Bering Sea to Puget Sound and with L, mochigarei in the southern Sea of Okhotsk. Synonymies, diagnoses, descriptions, and geographic distributions are provided for adults and larvae of all species; keys are provided for adults. Descriptions of early juveniles of eastern North Pacific species are also presented. Under the name of L. bilineata, L. polyxystra n. sp, has been the subject of many studies of eastern North Pacific Lepidopsetta. All previous studies of specimens from the southeastern Bering Sea into Puget Sound should be considered applicable at the generic level only, unless voucher specimens are verifiable.