Two new species of deepwater cardinalfish from the Indo-Pacific, with a definition of the Epigonus pandionis group (Perciformes: Epigonidae)

Two new Indo-Pacific species of deepwater cardinalfish, Epigonus lifouensis and E. tuberculatus are described based on the specimens collected from the Loyalty Islands and Cocos-Keeling Islands, respectively. These species belong to the Epigonus pandionis group defined as lacking an opercular spine, having more than 43 pored lateral-line scales to the end of the hypural and dorsal-fin rays VII-I, 9-11. Epigonus lifouensis is distinguished from other members of the group by a combination of the following characters: ribs present on the last abdominal vertebra; tongue toothless; tubercle absent on inner symphysis of lower jaw; eye elliptical; total gill rakers 24-25; pectoral-fin rays 18-19; pyloric caeca 10-13; body depth 17.0-17.1 % SL; and posterior half of oral cavity and tongue black. Epigonus tuberculatus is distinguished from other members of the group by a combination of the following characters: ribs on the last abdominal vertebra reduced or absent; tongue toothless; tubercle present on inner symphysis of lower jaw; total gill rakers 21-22; pectoral-fin rays 19-20; pyloric caeca 8-10; orbital diameter 14.5-15.4 % SL; and lower-jaw length 16.0-17.6 % SL. A key to the species and some comments on the group are provided based on examination of all members (nine species, including two new species) of the group.