Callogobius clarki ( Goren 1978 )

Delventhal, Naomi R., Mooi, Randall D., Bogorodsky, Sergey V. & Mal, Ahmad O., 2016, A review of the Callogobius (Teleostei: Gobiidae) from the Red Sea with the description of a new species, Zootaxa 4179 (2), pp. 225-243 : 235

Callogobius clarki ( Goren 1978)

( Figure 4 )

Drombus clarki Goren 1978: 200 (El-Tur, Sinai coast, Egypt, Gulf of Suez, Red Sea; holotype HUJ 10065).—Goren 1979: 36. Callogobius bifasciatus (non Smith)— Randall et al. 1994: 240; Randall 1995: 330; Golani & Bogorodsky 2010: 46. Callogobius clarki — Goren 1980: 213; Dor 1984: 241; Goren et al. 1991: 300; Goren & Dor 1994: 63; Delventhal & Mooi

2014: 143.

Diagnosis. Callogobius clarki is distinguished from congeners by the following combination of characters: head pores absent; scales in lateral series 33–41; scales mostly cycloid except for ctenoid scales occasionally on caudal peduncle; preopercular papillae row (Row 20) not continuous with transverse opercular row (Row 21).

Brief description. Moderately stout-bodied with rounded caudal fin <40% SL in length. Scales small, cycloid except for a few rows at caudal-fin base (larger specimens may lack ctenoid scales, although exceptionally long ctenii may be present on caudal peduncle scales), scales in lateral series 33–41. Dorsal-fin rays VI + I,10–11 (rarely 11); anal-fin rays I,8–9 (usually 9); pectoral-fin rays 15–17; pelvic fins united two-thirds of their length, with fifth ray shorter than fourth with weak frenum. Anterior nostril slightly longer than posterior nostril. Head pores absent. Preopercular papillae row (Row 20) not continuous with transverse opercular row (Row 21); more than 10 transverse mandibular papillae rows (Row 16) on each side.

Head, body and median fins finely mottled whitish and grey-brown with irregular broad, dark brown bar below first dorsal fin extending onto fin as one or two spots at base. Second broad, oblique, dark bar extending from mid to posterior base of second dorsal fin to posterior base of anal fin and anterior caudal peduncle. A dark bar posteriorly on caudal peduncle at caudal-fin base. Wide, diffuse brown bar or blotch present on ventral half of body below origin of second dorsal fin. Sensory papillae ridges on head with dark brown spots. Pectoral fin mostly translucent with diffuse vertical, narrow, brown bands and sometimes dense markings medially. Coloration of preserved material similar to fresh coloration.

Distribution and habitat. Reported only from the Red Sea. Callogobius clarki is often found under stones or at the base of corals in fringing seaward reefs and patches of corals in lagoons and bays at a depth of up to at least 12 m.

Remarks. Callogobius clarki differs from all other Callogobius species in the Red Sea in lacking head pores. Juvenile specimens of C. flavobrunneus and C. sclateri that have not yet developed head pores may be confused with C. clarki . Unlike C. flavobrunneus , C. clarki has ctenoid scales only on the caudal peduncle, pelvic fins united, and a weak frenum (vs. ctenoid scales on the posterior half of the body, separate pelvics or united by only a minute membrane, and no frenum). Callogobius clarki has higher lateral scale counts than C. sclateri (33–41 vs. 28–31) and pelvic fins partially united with a weak frenum (vs. separate with no frenum). Live C. clarki may closely resemble C. flavobrunneus , due to similar body shape and coloration (they may have flavobrunneus -like medial markings on the pectoral fins); examination with the aid of a microscope may be needed to distinguish them.

Representative Red Sea material (35 specimens, 16.8–52.0 mm SL). Egypt: BPBM 41226 , female, 23.9 mm SL ; BPBM 41243 , male, 52.0 mm SL, Dahab , large coral block, 14 m, coll. S.V. Bogorodsky, 0 1 August 2015 ; HUJ 10065, holotype, female, 36.5 mm SL; ROM 50227, male, 34.9 mm SL; USNM 220031, 11 specimens, 4 males, 3 females, 1 juvenile, and 3 specimens cleared and stained, 14.1–35.1 mm SL; USNM 220090, male, 43.7 mm SL; USNM 296954, 1 male and 1 juvenile, 16.8–24.2 mm SL; USNM 341181, male and female, 31.0– 47.9 mm SL; USNM 300015, female?, 23.6 mm SL; Eritrea: USNM 220038, 2 males, 34.6–48.6 mm SL ; Saudi Arabia: KAUMM 380 (KAU13-218), male, 25.2 mm SL, Al Wajh bank, fringing reef of small island, 5–8 m, coll. S.V. Bogorodsky & T.J. Alpermann, 12 June 2013 ; KAUMM 381 (KAU13-292), male, 29.4 mm SL, 25 km south of Al Wajh , fringing reef, 5–7 m, coll. S.V. Bogorodsky & T.J. Alpermann, 13 June 2013 ; KAUMM 382 (KAU13- 491), female, 34.6 mm SL, 25 km south of Al Wajh , fringing reef, 11–14 m, coll. S.V. Bogorodsky & T.J. Alpermann, 16 June 2013 ; SMF 35755, male, 21.5 mm SL, Amaq , fringing reef, 7 m, coll. S.V. Bogorodsky & T.J. Alpermann, 31 March 2011 ; SMF 35763, female, 23.7 mm SL, Farasan Island, isolated coral patch of lagoon, 3–5 m, coll. S.V. Bogorodsky & T.J. Alpermann, 28 February 2012 ; SMF 35765 (KAU13-212), female, 36.4 mm SL, Al Wajh bank, sediment with coral patches, 3–5 m, coll. S.V. Bogorodsky & T.J. Alpermann, 12 June 2013 ; SMF 35766 (KAU13-291), female, 41.4 mm SL, 25 km south of Al Wajh , fringing reef, 5–7 m, coll. S.V. Bogorodsky & T.J. Alpermann, 13 June 2013 ( Fig. 7 ) ; SMF 35767 (KAU13-217), male, 37.2 mm SL, Al Wajh bank, fringing reef of small island, 5–8 m, coll. S.V. Bogorodsky & T.J. Alpermann, 12 June 2013 ; SMF 35768 (KAU13-381 & 382), 2 females, 31.6–33.6 mm SL, 30 km south of Al Wajh , fringing reef, 8 m, coll. S.V. Bogorodsky & T.J. Alpermann, 14 June 2013 ; SMF 35769 (KAU13-454), male, 42.3 mm SL, 25 km south of Al Wajh , fringing reef, 11–14 m, coll. S.V. Bogorodsky & T.J. Alpermann, 16 June 2013 ; Sudan: BMNH 1978.9 .8.6, male, 38.8 mm SL.

Figures

FIGURE 4. Callogobius clarki (Goren), live coloration: A. SMF 35766, female, 41.4 mm SL, Al Wajh, Saudi Arabia; B. BPBM 41243, male, 52.0 mm SL, Dahab, Egypt. Photos by SVB.

FIGURE 7. A. Callogobius sclateri (Steindachner), preserved specimen, USNM 298419, female, 22.1 mm SL, Ras Burqa, Gulf of Aqaba, Egypt. B. Callogobius sp. A, live coloration, SMF 35772, juvenile, 14.5 mm SL, Yabua Island, Saudi Arabia. Photos by RDM (A), SVB (B).