Gymnothorax undulatus ( Lacepède 1803 ), sensu Randall & Golani, 1995

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 : 58-60

Gymnothorax undulatus ( Lacepède 1803) —Undulated Moray

( Figure 38 )

Muraenophis undulata Lacepède (ex Commerson) 1803: 629, 642, pl. 19 (fig. 2) (No locality). Holotype (unique), whereabouts unknown.

? Muraena undulata: Klunzinger 1871: 615 (Quseir, Egypt).

? Gymnothorax meleagris (non Shaw & Nodder): Fowler & Steinitz 1956: 270 (Eilat).

Gymnothorax undulatus: Randall & Golani 1995: 868 (in part: Pl. 2F); Debelius 1998: 13; Lieske & Myers 2004: 36; Golani & Bogorodsky 2010: 10; Golani & Fricke 2018: 23.

Red Sea material. Red Sea: USNM 47604 (1, 490). Egypt: USNM 312603 (1, 674), Gulf of Aqaba, Marsa Muqabila. Saudi Arabia: USNM 147430 (1, 500), Gubat Ashra. Eritrea: USNM 312608 (1, 357), Dahlak Archipelago, Delemmi.

Comparative material. Arabian Gulf: BPBM 29469 (1, 693); BPBM 33383 (1, 760); BPBM 33384 (2, 432– 533). Mauritius: BPBM 20132 (1, 207). Chagos Archipelago: USNM 312615 (5, 263–407). Madagascar: MNHN B.2426 (1, 400); MNHN B.2432 (1, 317); MNHN B.2728 (1, 434); MNHN 1965-338 (1, 206); MNHN 1991-0402 (3, 49 8–595). Mozambique: SAIAB 60389 (1, 223). South Africa: SAIAB 60166 (9, 80–360); USNM 312712 (1, 570); USNM 330982 (1, 454). Wallis I.: USNM 371033 (1, 141).

Description. In TL: preanal length 2.1–2.4, predorsal length 7.8–11, head length 6.6–8.2, body depth at anus 12–21. In head length: snout length 4.6–6.4, eye diameter 6.4–12, upper-jaw length 2.2–2.9. Pores: LL 2, SO 3, IO 4, POM 6. Vertebrae: predorsal 3–6, preanal 50–58, total 126–136.

Body moderately elongate; anus before midlength; dorsal-fin origin before gill opening. Snout moderate, jaws of equal length. Eye moderate, over middle of upper jaw. Anterior nostril tubular; posterior nostril above anterior part of eye.

Teeth conical, pointed, smooth. Intermaxillary teeth in a single peripheral series, 2–6 on each side; 2–4 median teeth, usually 3. Maxillary teeth uniserial or biserial, with 1–2 larger inner teeth anteriorly, about 9–18 smaller outer teeth. Dentary teeth biserial, with 2–4 larger inner teeth anteriorly, 16–20 smaller outer teeth. Vomerine teeth uniserial but biserial in 1 specimen, about 4–7.

Color: variable over range. In Red Sea, small individuals with body and fins dark gray to black with narrow pale markings arranged in a reticular pattern. Larger individuals more grayish, pattern becoming more irregular and obscure. Top of head olive-green to yellow-green, densely spotted with small irregular dark brown spots posteriorly; snout and lower jaw yellow-green to light grey-brown without spots; corner of mouth with a white spot. Outside Red Sea most commonly dark brown to black, with narrow pale markings usually interconnected to form a reticulation; the pattern generally more obscure in larger specimens. One specimen (BPBM 33383, 760 mm, from Jana Island, Arabian Gulf), apparently of this species, dull whitish with small, irregular black spots.

Maximum size about 1.5 m.

Distribution and habitat. Widely distributed in the Indo-Pacific from the Red Sea and East Africa eastward to the islands off Central America. Mainly in shallow water, common on coral reefs, reported from depths of 1– 110 m.

Remarks. As pointed out above, this species was confused with Gymnothorax pharaonis n. sp. described here. Gymnothorax undulatus is highly variable over its range, and further study may show that it represents a complex of species. Specimens examined from the Red Sea and Arabian Gulf have fewer vertebrae (126–129) than those from Mauritius and Chagos Archipelago (130–134) and South Africa (134–136). The specimen from Wallis Island has 131. The South African specimens differ further in coloration, showing a densely spotted, gravel-like pattern rather than reticulations (see Pl. 57E in Smith 1962).

Randall & Golani (1995: 868) listed Klunzinger’s (1871) record of Muraena undulata and Fowler & Steinitz’s record of Gymnothorax meleagris in their synonymy of Gymnothorax undulatus , but as they confused G. undulatus with G. pharaonis , these may refer to the latter species instead. No Red Sea specimen was collected during this study and no sequences of the mitochondrial COI barcoding gene were available for other Red Sea specimens of G. undulatus . We therefore included COI sequences of each of two closely related clades for which COI sequences could be retrieved from various databases. One clade was largely restricted to the Indian Ocean and the other to the Pacific Ocean. However, as the type locality of the species is not documented, the whereabouts of the holotype is unknown, and we did (with the exception of one South Pacific specimen) examine only Red Sea and Indian Ocean material herein, we refrain from guessing which of the two clades might represent Gymnothorax undulatus and if the other clade represents another species. Hence, both clades are under the name G. undulatus in the presented phylogeny ( Fig. 48 ), where they form part of a highly supported clade with G. punctatus .

Figures

FIGURE 38. Gymnothorax undulatus. A: Dahab, Egypt; B: Dahab, Egypt. Photos by S.V. Bogorodsky.

FIGURE 48. Unrooted maximum likelihood phylogeny of Indo-Pacific moray eels (Muraenidae) based on partial mitochondrial COI. Branch support values were obtained by 100 bootstrapped replicates; only bootstrap values above 50 percent are shown. The scale bar represents average number of nucleotide substitutions. (A) = specimen sequenced in this study; (B) = sequence retrieved from BOLD; (C) sequence retrieved from CRIOBE; (G) = sequence retrieved from GenBank; (R) = sequence retrieved from Reece et al. (2010); (ID) = species ID re-assigned herein; (ID-H) = specimen re-assigned as of Huang et al. (2019); (SAU) = collected in Saudi Arabia; (ISR) = collected in Israel.