Pleurosicya bilobata ( Koumans, 1941 )

Goren, Menachem, Bogorodsky, Sergey V. & B-S, Shevy, 2023, How many valid Pleurosicya (Teleostei: Gobiidae) species are known from the Red Sea?, Zootaxa 5258 (1), pp. 113-129 : 120

Pleurosicya bilobata ( Koumans, 1941) , new record for the Red Sea Bilobed Ghostgoby

Figure 2

Cottogobius bilobatus Koumans, 1941: 253 . Type locality: Muthivaratu Paar, India; lectotype: USNM 203588. This species is the type species of the genus Cottogobius Koumans, 1941 which is a junior synonym of Pleurosicya Weber, 1913 ( Larson 1990) .

Distinctive characters (following Koumans 1941, pp. 253–254 and Larson 2022, p. 122). Pectoral-fin rays 16– 19 (usually 17–18); midline of nape and side of nape naked; gill opening broad, extending forward usually to a vertical at posterior edge of eye; tip of tongue bilobed; translucent green to greenish brown, with indistinct brown to yellowish brown bars on body and bands on head; males with a black spot posteriorly on second dorsal fin.

Description (following Koumans 1941 and Larson 2022). Small fish, less than 30 mm in total length. Body elongate and compressed. Head depressed. Mouth terminal. Maxilla extending to below anterior margin of pupil. Upper and lower jaws with bands of small teeth, outer enlarged; inner lateral teeth in lower jaw enlarged, two pairs of them are canine-shaped. Tip of tongue bilobate. Vomer with a considerable protuberance. Gill opening extending to a vertical at posterior edge of eye.

Fins: Dorsal-fin rays VI + I,7–8; anal-fin rays I,7–8 (given in the description of the genus); pectoral-fin rays 16–19, lower 3–7 rays unbranched and thickened distally. Pelvic-fin rays I,5, pelvic fins united, cup-shaped. Frenum well developed, laterally with a rounded lobe. Fleshy lobes at each side of the frenum.

Scales: ctenoid, 26–27 (23–29 sensu Larson (2022)) in longitudinal series along the body, 6–7 transverse rows. Scales on side of body extending forward to above pectoral-fin base, side of breast usually scaled, mid predorsal and side of nape naked.

Colour (alive, based on original photos). Translucent green ( Fig. 2A ) to greenish brown ( Fig. 2B ), with indistinct irregular brown bars on body, except on belly and breast; a brown band on head from front of the eye to upper lip; eyes golden-brownish with a red ring around the eye pupil; males with a black spot posteriorly on the second dorsal fin.

Distribution and Habitat. Pleurosicya bilobata is widely distributed from the Red Sea, Mauritius (Cargados Carajos Shoals), India and Comoros Islands (e.g., ROM 60051) in Western Indian Ocean, in the western Pacific east to Australia (New South Wales), Japan (Ryukyu Islands), and Mariana Islands. It generally lives on seagrass, at depths of 8–30 m ( Larson 1990).

Remarks. Two photographed individuals match the description of P. bilobata ( Larson 1990) . We herein report the finding of this species in the northern Gulf of Aqaba, a new record for the Red Sea. This report is based solely on underwater photographs taken from Mashraba Bay at Dahab, Gulf of Aqaba ( Fig. 2A & B ). Both individuals were found in the seagrass area at depths of 8– 12 m.

Figures

FIGURE 2. Pleurosicya bilobata. A: Dahab, Egypt, Red Sea; B: Dahab, Egypt, Red Sea. Photos by T. Malkerova (A), C. von Mach (B).