Redescription of Platycephalus angustus Steindachner 1866 (Teleostei: Platycephalidae), a valid flathead in northern Australia and New Guinea

摘要

The platycephalid Platycephalus angustus Steindachner 1866, which has not appeared in recent publications, is recognized as valid and redescribed on the basis of 24 specimens collected from northern Australia and New Guinea. This species is easily separable from other congeners in having a combination of the first dorsal fin usually with two small anterior isolated spines, dorsal and anal soft rays usually 13, orbit relatively small (orbital diameter 11.221.5p% HL), postorbital region long (postorbital length 55.567.8p% HL), interorbital space wide (interorbital width 7.317.3p% HL), suborbital region narrow (suborbital width 4.77.2p% HL), vomerine tooth rows tending to increase in number with growth, with 24 rows in 106184pmm SL specimens and a single broad band of numerous rows in larger specimens, teeth present on the dorsal surface of the premaxilla anterolaterally on the edge of the upper jaw in specimens ca. 76pmm SL or longer, and 35 dark brown to black bands and spots on its caudal fin. As the stated type locality, Surinam, is considered erroneous, and the holotype appears to have been lost, a neotype is designated with a type locality northeast of Darbilla Creek, Millingimbi, Northern Territory, Australia.