A new species, Trichiurus australis (Perciformes: Trichiuridae), from Australia

Abstract

Trichiurus australis, a new trichiurid fish, is described on the basis of four specimens collected off Burnett River mouth, Pialba and Thursday Island, Queensland, Australia. The new species strongly resembles Trichiurus brevis Wang and You, 1992 (distributed in the South China Sea), T. russelli Dutt and Thankam, 1967 (the northwestern Bay of Bengal and the northern Gulf of Thailand), and T. nickolensis Burhanuddin and Iwatsuki, 2003 (northwestern Australia) in having the highest point of the supraoccipital crest situated directly above the posterior margin of the eye and being relatively small in size (less than ca. 700 mm in total length: TL). It differs from those three species in having spinescent gill rakers almost with 2 equally long cusps [vs. (1, rarely 2 but 1 of them clearly shorter than another)], posterior caudal peduncle vertebrae bearing neural spines (vs. neural spines absent), longer caudal peduncle length (mean 16% TL vs. 6% in T. brevis, 8% in T. nickolensis, and 8% in T. russelli), and shorter precaudal length (83% vs. 93%, 91%, and 91%), preanal length (26% vs. 33%, 31%, and 35%), and head length (9% vs. 12%, 11%, and 13%). We have tentatively classified this new species under the “Trichiurus russelli complex” because the foregoing diagnostic characters are identical to this species complex except for the presence of neural spines in the posterior caudal vertebrae.