Epigonus denticulatus Dieuzeide 1950
- Dataset
- A review of the deepwater cardinalfish genus Epigonus (Perciformes: Epigonidae) of the Western Indian Ocean, with description of two new species
- Rank
- SPECIES
Classification
- kingdom
- Animalia
- phylum
- Chordata
- class
- Actinopterygii
- order
- Perciformes
- family
- Epigonidae
- genus
- Epigonus
- species
- Epigonus denticulatus
description
Measurements (% SL); counts are given in Table 1. Head length 32.4 – 35.7; head width 14.8 – 16.2; head height 15.1 – 17.4; body depth 18.0 – 21.4; body width 12.4 – 15.3; caudal-peduncle depth 8.3 – 9.8; caudal-peduncle length 27.5 – 30.8; orbital diameter 13.3 – 15.9; interorbital width 8.1 – 9.6; postorbital length 12.1 – 14.9; upper-jaw length 13.5 – 15.7; lower-jaw length 15.3 – 17.8; snout length 6.4 – 8.0; pre-first dorsal-fin length 36.2 – 38.6; presecond dorsal-fin length 56.3 – 61.0; pre-pectoral-fin length 32.0 – 35.6; pre-pelvic-fin length 33.0 – 35.7; pre-anus length 54.0 – 57.4; pre-anal-fin length 62.0 – 65.5; first spine length on first dorsal fin 2.5 – 4.1; second spine length on first dorsal fin 10.2 – 13.3; third spine length on first dorsal fin 12.4 – 14.1; second dorsal-fin spine length 5.5 – 7.7; first anal-fin spine length 2.1 – 3.3; second anal-fin spine length 5.3 – 7.9; pelvic-fin spine length 7.3 – 10.4; first dorsal-fin base length 10.3 – 13.3; second dorsal-fin base length 8.6 – 11.5; anal-fin base length 8.1 – 10.9; pectoral-fin length 14.1 – 19.9; pelvic-fin length 12.2 – 15.6.
diagnosis
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 not reach level of origin of second dorsal fin, pectoral-fin length 14.1 – 19.9 % SL.
distribution
Distribution. Western South Indian Ocean (Shcherbachev 1987; Abramov 1992); Gulf of Mexico (Mayer 1974; McEachran & Fechhelm 2005); Caribbean Sea (Mayer 1974); Eastern Atlantic including Mediterranean (Dieuzeide 1950; Mayer 1974; Abramov 1992; Ruiz-Pico et al. 2012); Tasman Sea, Australia and New Zealand (Paulin et al. 1989; Abramov 1992; Stewart & Gon 2015); western South Atlantic (Abramov 1992); Emperor Seamounts (Chen 1980; Mundy 2005); Japan (Machida 1985; Hayashi 2013), at 75 – 850 m depth. Comparisons and Remarks. Epigonus denticulatus belongs to the E. pandinonis group (Okamoto & Motomura 2013). This species is similar to E. elongatus in having a slender body and lacking a opercular spine (Fig. 8); however, it differs from E. elongatus in having 28 – 34 gill rakers (22 – 23 in E. elongatus) and a pair of ribs on the last abdominal vertebra (vs. absent on these ribs in E. elongatus). Epigonus denticulatus is similar to E. marisrubri, also a member of the E. pandionis group in the Western Indian Ocean, but most of specimens of E. denticulatus have no tooth patch on the tongue (vs. tooth patch present in E. marisrubri) and a short pectoral fin (not reaching level of the origin of second dorsal fin, 14.1 – 19.9 % SL, vs. reaching level of the origin of second dorsal fin, 24.3 – 26.0 % SL in E. marisrubri). Furthermore, E. denticulatus can be distinguished from E. angustifrons, E. macrops, and E. telescopus in having 28 – 34 gill rakers (vs. 33 – 36 in E. angustifrons, 18 – 20 in E. macrops, and 23 – 26 in E. telescopus) and in lacking an isolated dorsal fin spine between first dorsal and second dorsal fins (vs. present in E. angustifrons, E. macrops, and E. telescopus). Epigonus exodon has a small number of pored lateral-line scales (35 – 37 vs. 45 – 49 in E. denticulatus) and anteriorly projecting teeth on the symphysis of lower jaw (absent in E. denticulatus). The remaining seven species of the genus in the Western Indian Ocean, E. bispinosus, E. idai, E. lenimen, E. marimonticolus, E. pectinifer, E. robustus, and E. waltersensis, are characterized by having a pungent opercular spine as members of the E. constanciae group (opercular spine absent in E. denticulatus).
materials_examined
Material examined. SAIAB 193759, 120.0 mm SL, 34 ° 11 S, 25 ° 17 E, St. Francis Bay, Eastern Cape, South Africa, date unknown; SAIAB 20561, 145.0 mm SL, 35 ° 53 S, 20 ° 57 E, southeast of Cape Agulhas, Western Cape, South Africa.
Name
- Synonyms
- Epigonus atherinoides (Gilbert 1905)
- Homonyms
- Epigonus denticulatus Dieuzeide 1950