Pomatoschistus quagga (Heckel, 1837) (Fig. 70)—Quagga Goby

Gobius quagga Heckel, 1837: 150, Pl. 9 (figs. 5–6); type locality: Mediterranean Sea, Italy, Sicily, Palermo .

Size. Maximum size 4.6 cm total length (Miller 1986).

Morphology. D VI (VI–VII) + I,9; A I,8–9; P 15 (Miller 1986). Small goby with subcylindrical body, laterally compressed towards caudal fin. Small head with short pointed snout. Eyes lateral. Caudal peduncle long and slender, clearly lower than body depth. Dorsal fins of similar height, the first dorsal fin with more or less rounded margin and no elongated spines. Caudal fin truncate to slightly emarginate. Scales more or less visible on body from reticulate pattern of pigmentation along scale edges.

Live coloration. Background color pale beige to light gray, sometimes partly translucent, with variable dark or white patterns. When discernible, vertical black streaks (4–5 in males, 3 in females), restricted to the ventral two-thirds of body, typical for this species. Often 5 pale to golden dorsal saddles, the first, small and often faint, below first dorsal fin, the fifth just above the dark midlateral triangular blotch at caudal-fin base (Fig. 70). In translucent individuals, 4 deep elongated dark blotches run along the vertebral column (in addition to the caudal spot). Cheeks usually pale without dark markings. A dark, reddish or pinkish oblique stripe on gill cover, sometimes bifurcating on its lower part, somewhat reminiscent of the Y-mark of P. bathi .

Similar species. Pomatoschistus bathi, P. knerii, Pseudaphya ferreri .

Habitat. Infralittoral species observed between 2–35 m depth, often in schools of ten to several hundred specimens, swimming up to 1 m above ground or resting on the substrate. They can be found on bedrock with macroalgae, more or less covered with sand, on coarse to muddy sand, or near Posidonia seagrass beds (Kovačić 2003, Louisy, unpublished data).

Geographic distribution. A Mediterranean species, known along the north coast from Alboran Sea to Aegean Sea (summarized by Patzner 2021) .