18. Ambassis gymnocephalus (Lacepède, 1802), Native, New record

Fig. 44

Etymology: Ambassis: derived from Greek, anabasis = climbing up; gymnocephalus: short head.

Common name: Bald Glassy.

Taxonomy: Lutjanus gymnocephalus was described by Lacepède [B. G. E.] (ex Commerson) 1802:181, 216 [Histoire naturelle des poissons (Lacepède) v. 4] from Le grand Océan équinoxal or dans les parties de ce grand Océan voisines des tropiques” [Indo-Pacific].

Holotype: No types known.

Synonyms: Lutianus gymnocephalus Lacepede, 1801: PI. 23, fig. 3, 1802: pp. 181, 216 (Indo-Pacific). Ambassis gymnocephalus: Smith, 1961: 246; Hill, 1966: 22; Winterbottom, 1976: 62.

Short description: A large deep-bodied glassfish, with a relatively small head, dorsal-fin rays VIll, 8–10; anal-fin rays III, 8–10; pectoral-fin rays 14–15; lateral line interrupted, with 12–13 pored scales + 12–13; gill rakers (8–10) + (22–25); 2 rows of cheek scales. Supraorbital spines 1–5 (usually 3 or 4, Oman specimens 2 or 3); lower edge and angle of preopercle serrate; preopercle ridge completely serrate along lower limb; a large retrorse spine on preorbital just below anterior nostril; preorbital ridge smooth or serrate; interopercle smooth except for 1 or (rarely) 2 small spines. A row of minute teeth on vomer, palatines and tongue.

General distribution: Indo-West Pacific: East and South Africa east to Philippines and New Guinea, north to Taiwan, south to Cairns (Queensland, Australia). Habitat: freshwater, brackish, marine.

Distribution in Oman: Al Bahayes, Muscat Governorate (Fig. 45). It is a richly vegetated Wadi, adjusted to the Oman Sea coastal area.

Remarks: Ambassis gymnocephalus is a new fish record for the Oman inland waters.

Examined material: ZM-CBSU: O006.Ag101, 14, Oman: Qurum, 23°37’38”N, 58°29’00”E, H.R. Esmaeili, S.M. Al-Jufaili, A.H. Masoumi, Sep. 2021.