On the second record of the Antarctic plunderfish Artedidraco glareobarbatus (Artedidraconidae) from the Ross Sea

Abstract

A new species of Antarctic plunderfish, Artedidraco glareobarbatus, has recently been identified from two specimens collected in the Ross Sea. On the basis of additional material composed of two specimens and a new colour morph, meristic and morphometric data of the species is updated. A complete set of measurements and counts was made on the new specimens following the previous authors. An accurate description of the mental barbel, which represents a key diagnostic character in this family, is provided. In particular, on the basis of external morphology of skin of the terminal expansion, two different types of mental barbel can be distinguished: a typical form as described in the holotype and paratype, and a new form, found in two specimens, with the terminal expansion consisting of irregular processes similar to flattened and convoluted ridges separated by deep furrows. Finally, the new colour morph, represented by a spotted specimen, is also described in detail.