Gobius xanthocephalus Heymer & Zander, 1992 (Fig. 38)—Yellow-headed Goby

Gobius xanthocephalus Heymer & Zander, 1992: 305, type locality: western Mediterranean Sea, France, Banyuls-sur-Mer, Ile Grosse.

Size. Known adult size about 9 cm total length.

Morphology. D VI + I,13–16; A I,13–15; P 18–20. Medium-sized goby with moderately elongate body, large head, and a short, slightly acute and oblique snout. Caudal peduncle deep, but lower than body. Dorsal fins of similar height, the first dorsal fin may be slightly higher in appearance, with more or less rounded distal edge and no elongate spines. Caudal fin rounded.

Scales present on body and on predorsal area, usually visible on photographs at least on body.

Live coloration. Head yellowish, more intensely on the snout and in the interorbital space, contrasting with a light gray or whitish body (Fig. 38). Head and body covered with longitudinal lines of well-defined orange to dark red dots. Eyes with brown stripes radiating from the pupil over iris to the orbital rim, 2 of them constituting a broad horizontal stripe across the pupil; the upper eye radial stripes are connected by an irregular longitudinal curved line (Fig. 38b). Upper lip with orange markings. Lower lip with a median W-shaped mark. Snout with Mshaped line and an oblique preorbital bar (Fig. 38b). One isolated brown to dark red dot at the corner of the mouth, followed by 2 short horizontal dashes (Fig. 33e).

Similar species. Gobius auratus morph 2, G. fallax .

Habitat. Infralittoral species, known from 1–36 m depth (Heymer & Zander 1992; Wirtz & Herrera 1995) on hard (e.g., bedrock, coralligenous) or mixed bottoms (e.g., sandy patches with pebbles, boulders, and seagrass).

Geographic distribution. Northeastern Atlantic, Mediterranean and Black Sea. In the Mediterranean, recorded in the northwestern Mediterranean (Miller 1986), including the Balearic Island of Ibiza (Fisher et al. 2007) and Corsica (Francour et al. 2010). Isolated populations confirmed in Crimea (Boltachev et al. 2009) and in the eastern part of the Black Sea (Vasil’eva & Bogorodsky 2004). In the Atlantic Ocean: from Galicia, Northern Spain (Villegas-Riìos & BanÞoìn 2010) to the Canary Islands (Wirtz & Herrera 1995).