Epigonus marisrubri Krupp, Zajons & Khalaf, 2009

Okamoto, Makoto & Gon, Ofer, 2018, A review of the deepwater cardinalfish genus Epigonus (Perciformes: Epigonidae) of the Western Indian Ocean, with description of two new species, Zootaxa 4382 (2), pp. 261-291 : 279-280

Epigonus marisrubri Krupp, Zajons & Khalaf, 2009

(New English name: Red Sea Deepwater Cardinalfish) ( Figs. 2 , 15 ; Tables 1, 2)

Epigonus marisrubri Krupp, Zajonz & Khalaf, 2009: 224 , fig. 1 (original description; type locality: ca. 29°27.30 N, 34°58.30 E, Northern of Gulf of Aqaba, Red Sea, Jordan, 52 m depth; holotype: SMF 24661); Okamoto & Motomura, 2013: 307 (record and key, Gulf of Aden).

Material examined. SMF 24661, holotype, female, 136 mm SL, ca. 29°27.30 N, 34°58.30 E, Gulf of Aqaba, Red Sea, Jordan, 52 m depth, 2 May 1990 (photograph) ; SMF 31636, paratype, 134 mm SL, collected with holotype ; USNM 269827 , 2 specimens, 84.3–88.4 mm SL, 11°24 N, 51°35 E, Somalia, western South Indian Ocean , 75–175 m depth, 17 December 1964 ; USNM 305950 , 139.8 mm SL, 12°03 N, 50°54 E, Gulf of Aden, 100–200 m depth, 7 November 1989.

Diagnosis. Dorsal-fin rays VII-I, 10; pectoral-fin rays 17–18; total gill rakers 28–30; vertebrae 10 + 15; pyloric caeca 9–10; pored lateral-line scales 47–49 + 3; scales below lateral line 9–10; opercular spine absent; maxillary mustache-like processes absent; ribs on last abdominal vertebra present; pectoral fin reaching level of origin of second dorsal fin; tooth patch present on tongue.

Measurements (% SL); counts are given in Table 1. Head length 31.9–36.8; head width 16.1–18.3; head height 17.4–18.5; body depth 20.3–24.5; body width 13.2–17.6; caudal-peduncle depth 8.3.5–10.7; caudalpeduncle length 25.0–27.7; orbital diameter 11.6–15.1; interorbital width 8.4–8.8; postorbital length 13.6–16.4; upper-jaw length 14.4–15.9; lower-jaw length 17.4–18.5; snout length 7.5–8.7; pre-first dorsal-fin length 38.2– 40.8; pre-second dorsal-fin length 59.6–62.9; pre-pectoral-fin length 32.1–39.3; pre-pelvic-fin length 34.3–41.3; pre-anus length 59.7–63.2; pre-anal-fin length 65.0–68.9; first spine length on first dorsal fin 5.0–7.5; second spine length on first dorsal fin 13.3–15.9; third spine length on first dorsal fin 14.1–17.0; second dorsal-fin spine length 4.6–5.8; first anal-fin spine length 2.1–2.4; second anal-fin spine length 5.3–5.9; pelvic-fin spine length 6.9–9.9; first dorsal-fin base length 11.6–15.4; second dorsal-fin base length 10.7–11.5; anal-fin base length 10.2–10.9; pectoral-fin length 19.0–26.0; pelvic-fin length 11.6–17.1.

Distribution. Red Sea ( Krupp et al. 2009); Gulf of Aden ( Okamoto & Motomura 2013), Somalia (present study); at 52–200 m depth.

Comparisons and Remarks. Epigonus marisrubri belongs to the E. pandionis group in having more than 43 pored lateral-line scales and lacking an opercular spine and an isolated dorsal fin spine between first and second dorsal fins ( Okamoto & Motomura 2013). This species is similar to E. exodon by having tooth patch on the tongue; however, it differs in having 47–49 pored lateral-line scales and 29–30 total gill rakers (vs. 35–37 pored lateral-line scales and 26–28 total gill rakers in E. exodon ), and in lacking anteriorly projecting teeth on the symphysis of lower jaw (vs. present in E. exodon , Fig. 10 ). Epigonus pectinifer also has a slender tooth patch on the tongue, but can be distinguished from E. marisrubri in having a pungent opercular spine and 9 soft rays on the second dorsal fin (vs. opercular spine absent and 10 soft rays on the second dorsal fin in E. marisrubri ; Fig. 15 ). In the remaining 11 species of the Western Indian Ocean, there is no tooth patch on the tongue.

We found two additional specimens of E. marisrubri from Somalia (USNM 269827), representing the first record of the species from that area. All specimens were collected from coastal reef areas and the continental shelf ( Okamoto & Motomura 2013; present study).

Figures

FIGURE 2. Distribution of three species of the Epigonus pandionis group in the Western Indian Ocean.

FIGURE 10. Epigonus exodon, MNHN 1991-0155, holotype, 97.0 mm SL. Overall body (A); and dorsal (B) and ventral (C) views of tipof the lower jaw, arrows show the anteriorly projecting teeth.

FIGURE 15. Epigonus marisrubri, SMF 24661, holotype, 136 mm SL.