Gymnothorax johnsoni ( Smith 1962 )

Smith, David G., Bogorodsky, Sergey V., Mal, Ahmad O. & Alpermann, Tilman J., 2019, Review of the moray eels (Anguilliformes: Muraenidae) of the Red Sea, with description of a new species, Zootaxa 4704 (1), pp. 1-87 : 37-38

Gymnothorax johnsoni ( Smith 1962) —Johnson’s Moray

( Figure 22 )

Lycodontis johnsoni Smith 1962: 438 , pl. 56 (figs. C–D) (Algoa Bay, South Africa, 40 fm [82 m]). Holotype, SAIAB 104.

Gymnothorax johnsoni: McCosker et al. 1993: 165 ; Baranes & Golani 1993: 302; Randall & Golani 1995: 861; Khalaf & Disi 1997: 39; Khalaf 2004: 36; Golani & Bogorodsky 2010: 10; Golani & Fricke 2018: 22.

Red Sea material. Israel: BPBM 35744 (1, 650), Eilat ; BPBM 18240 (1, 166), Gulf of Aqaba , Coral Island; HUJ 10432 (1, 310), Eilat; HUJ 17016 (1, 540), Eilat; HUJ 17017 (2, 810–865), Eilat . Egypt: BPBM 18167 (1, 236), Dahab .

Comparative material. South Africa: SAIAB 104 (1, 545, holotype) . Mozambique: SAIAB 5019 (1, 273, paratype) . Somalia: USNM 301970 (2, 235–413) . Mauritius: USNM 342128 (1, 105) .

Description. In TL: preanal length 2.1–2.4, predorsal length 6.6–9.9, head length 6.6–8.1, body depth at anus 16–24. In head length: snout length 4.6–5.6, eye diameter 7.4–12, upper-jaw length 2.1–2.8. Pores: LL 2, SO 3, IO 4, POM 6. Vertebrae: predorsal 5, preanal 50–55, total 131–140.

Body moderately elongate, anus slightly before midlength, dorsal-fin origin before gill opening. Jaws slender, of equal length. Eye moderate, over middle of upper jaw. Anterior nostril tubular, rather long, reaching lip when depressed; posterior nostril elliptical, without a raised rim, above anterior margin of eye.

Teeth smooth, slender and pointed or blade-like. Intermaxillary teeth long and slender, in a single peripheral series, 3–6 on each side; 3 slender, depressible median teeth. Maxillary teeth uniserial except in small specimens, which may have 1–4 larger, inner teeth anteriorly; about 9–14 smaller outer teeth. Dentary with 3 larger inner teeth anteriorly on each side and about 15–20 smaller teeth in one row. Vomerine teeth uniserial.

Color: smaller individuals brown with medium-sized round pale spots, covering body and commencing on posterior part of head, larger and more widely spaced posteriorly; spots extending onto fins, those on posterior fourth of dorsal fin are elongate. Spots on body become more closely spaced and irregular with growth. Corner of mouth and throat grooves dark. Edge of orbit narrowly dark brown.

Maximum size at least 880 mm.

Distribution and habitat. Recorded from the east coast of Africa from Algoa Bay, Madagascar and Mascarene Islands to Kenya, Somalia and the Red Sea. Typically living in deep waters, the deepest record from 400 m off Eilat ( Randall & Golani 1995). The holotype and paratype were collected from about 75 m; Baranes & Golani (1993) reported three specimens from depths of 150–200 m, one of them (HUJ 14147) is largest known for species (880 mm TL). The shallowest records reported by Randall & Golani (1995) were from depths of 15 and 49 m, and the Mauritian specimen was collected at 11– 13 m. All known records from the Red Sea are from the Gulf of Aqaba. McCosker et al. (1993) published the first record from the Red Sea.

Remarks. The specimen from Mauritius has distinctly fewer vertebrae than those from the African coast and the Red Sea (50 vs. 53–55 preanal, 131 vs. 137–140 total, respectively). It is also the smallest of the specimens examined, but no other obvious differences are evident. Böhlke & Smith (2002) noted that the overall appearance and the description of Muraena stellifer Richardson could suggest that it may be the senior synonym of G. johnsoni but may also be a junior synonym of G. punctatus , which also has white spots and a similar vertebral count. Later, Smith (2012) placed M. stellifer as incertae sedis because the holotype is in poor condition and cannot be identified. May be easily confused with the similar G. punctatus (see below). In the field surveys that were carried out during the present study, no specimens of G. johnsoni were collected. The two specimens for which COI data were available come from the Red Sea ( Israel) and the southwestern Indian Ocean ( South Africa). The latter sequence comes from a larva (BOLD entry DSLAG1244-11) that was originally assigned to G. prionodon Ogilby , but which was re-assigned here to G. johnsoni based on its genetic indistinctness (in COI) from the specimen from Israel. The fine-scale pattern of divergence among G. johnsoni and its closest relatives is not well resolved, but the species forms part of highly supported clade with a number of other species, including the new Red Sea species Gymnothorax pharaonis described in this study and the recently redescribed species G. mucifer Snyder ( Huang et al. 2019) .

Figures

FIGURE 22. Gymnothorax johnsoni, BPBM 35744, 650 mm TL, fresh specimen, Eilat, Israel. Photo by J.E. Randall.