Epigonus denticulatus Dieuzeide, 1950

Okamoto, Makoto, Chen, Wei-Jen & Motomura, Hiroyuki, 2020, New distributional records of three deepwater cardinalfishes Epigonus angustifrons, E. denticulatus, and E. exodon (Perciformes: Epigonidae) in the South Indian Ocean, Cybium 44 (2), pp. 165-168 : 166

Epigonus denticulatus Dieuzeide, 1950

( Fig. 3 ; Tab. I)

Material examined

Two specimens: CSIRO H 5408-01 (120.2 mm SL, male), CSIRO H 5408-02 (138.6 mm SL, male), 34°56.87’S, 81°11.92’E, St. Paul Seamount , central South Indian Ocean, 430-595 m depth, 1 May 1997, demersal trawl, FRV Austral Leader .

Diagnosis

Dorsal-fin rays VII-I, 10; pectoral-fin rays 18-21; total gill rakers 28-34; vertebrae 10 + 15; pyloric caeca 10-14; pored lateral-line scales 45-49 + 3-5; opercular spine absent, maxillary mustache-like processes absent; nub-like structures or spine on symphysis of lower jaw absent; ribs on last abdominal vertebra present; tongue toothless or rarely small tooth patch present; pectoral-fin length 14.1-19.9% SL, not reaching vertical at origin of second dorsal fin.

Distribution

Western and central South Indian Ocean; Gulf of Mexico; Caribbean Sea; eastern Atlantic including Mediterranean; Tasman Sea, Australia and New Zealand; western South Atlantic; Emperor Seamounts; Japan, at 75-850 m depth ( Abramov, 1992; Okamoto and Gon, 2018; present study: Fig. 2 ).

Remarks

The present specimens of E. denticulatus were collected with the two specimens of E. angustifrons from the central South Indi- an Ocean by the same trawl. In the Indian Ocean, E. denticulatus has been known from Australia and western South Indian Ocean ( Okamoto and Gon, 2018). The present specimens represent the first records of the species from the central South Indian Ocean. Epigonus denticulatus has a wide distributional range and is known as a member of the E. pandionis group by lacking the opercular spine, in having more than 43 pored lateral-line scales and VII-I, 10 dorsal-fin rays ( Okamoto and Motomura, 2013). The characters distinguishing E. denticulatus from E. angustifrons were mentioned above.

Figures

Figure 2. – Collection localities of Epigonus angustifrons (present study: Z; Okamoto and Gon, 2018: „), E. denticulatus (present study: Δ; Okamoto and Gon, 2018: A), and E. exodon (present study: C; Okamoto and Motomura, 2012: l) in the central and western South Indian Ocean.

Figure 3. – Epigonus denticulatus, CSIRO H 5408-02, 138.6 mm SL, central South Indian Ocean.