Review of the Australian hagfishes with description of two new species ofEptatretus(Myxinidae)

Abstract

This paper revises and updates taxonomic and distributional information about hagfishes (Myxinidae) from Australia. It covers five species of the genus Eptatretus: Eptatretus cirrhatus known from eastern Australia and also distributed around New Zealand, Eptatretus longipinnis endemic to South Australia, Eptatretus strahani originally described from the Philippines and reported here as a new record from Western Australia and two new species described herein as Eptatretus alastairi and Eptatretus gomoni, both from Western Australia. Eptatretus alastairi is distinguished from all congeners by the unique combination of the following characters: six pairs of gill pouches; three-cusp multicusps on the anterior and posterior rows of cusps; anterior unicusps 9-12; posterior unicusps 8-11; total cusps 48-56; prebranchial pores 13-16; branchial pores 5-6; trunk pores 50-55; tail pores 11-13; total pores 83-88; two bilaterally symmetrical nasal-sinus papillae in the dorsal surface of the nasal sinus. Eptatretus gomoni is distinguished from all congeners by the unique combination of the following characters: eight pairs of gill pouches; three-cusp multicusps on the anterior and two-cusp multicusps on the posterior row of cusps; anterior unicusps 10-11; posterior unicusps 9-10; total cusps 50; prebranchial pores 12-13; branchial pores 7-8; trunk pores 57-58; tail pores 14-15; total pores 91-93; no nasal-sinus papillae. An identification key for the Australian species of Eptatretus is also provided.