A systematic review of the fish genus Lycodapus (Zoarcidae) with descriptions of two new species

Abstract

Six of 11 nominal species of Lycodapus, L. australis Norman, L. derjugini Andriashev, L. dermatinus Gilbert, L. fierasfer Gilbert, L. mandibularis Gilbert, and L. parviceps Gilbert, are recognized. Original descriptions and the disintegrated type do not permit adequate diagnosis of L. extensus Gilbert, which we treat as a nomen dubium. The holotype of L. microchir Schmidt must be reexamined before the status of this nominal species can be assessed. We describe L. endemoscotus n.sp. and L. pachysoma n.sp. off the west coast of North America and another population of L. pachysoma from the Antarctic. The species of Lycodapus form two natural groupings. Long gill rakers and a tendency toward fewer preoperculomandibular head pores characterize L. australis, L. derjugini, L. dermatinus, and L. fierasfer. Short gill rakers, single interorbital pore, and more preoperculomandibular pores typify the remaining species of which L. endemoscotus, L. mandibularis, L. pachysoma, and another undescribed species from the Antarctic possess broad, stout rakers. Very reduced rakers indicate L. parviceps as the most differentiated of the short-rakered species. Descriptions, spot distribution maps, synonymies, and illustrations are provided for all named valid species.