Review of the Scorpionfish Genus Maxillicosta (Pisces: Scorpaenidae), with a Description of Three New Species from the Australian-New Zealand Region

The scorpionfish genus Maxillicosta Whitley, 1935, is expanded to include the genus Cristula De Buen, 1961. Each genus formerly consisted of a single species: Maxillicosta reticulata (De Buen, 1961) from Juan Fernández off the Chilean coast, M. scabriceps Whitley, 1935, from temperate waters of Australia. Besides these, two new Australian species, M. whitleyi and M. lopholepis, and a new species, M. raoulensis, from the Kermadec Islands in the southwestern Pacific, are described and illustrated. A key to the species is given. The closest relatives of the five species of Maxillicosta are fishes of the genus Neosebastes. Possible explanations of the distribution of Maxillicosta are discussed. A device for measuring interorbital depths is described.