ISTIGOBIUS RIGILIUS - (HERE, 1953)
Actinopterygii (Gigaclass) > Actinopteri (Class) > Teleostei (Subclass) > Gobiiformes (Order) > Gobiidae (Family) > Gobiinae (Subfamily) > Istigobius (Genus)
Brown-speckled sand-goby, Orange-spotted goby, Orangespotted sandgoby, Rigilius goby, Madara-kazarihaze,
Synonymes
Bikinigobius welanderi (Herre, 1953)
Istigobius rigillius (Herre, 1953)
Pallidogobius rigilius (Herre, 1953)
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Description
Dorsal spines (total): 7; Dorsal soft rays (total): 10-11; Anal spines: 1; Anal soft rays: 9 - 10; Vertebrae: 26. Upper pectoral fin rays entire. Predorsal with 7-9 cycloid scales; trunk with ctenoid scales. Segmented and non branching caudal rays 4, branching 13. Body color yellowish white; 2 brown diagonal lines from preoperculum to upper jaw, connected by a single line; 2 almost vertical brown lines on operculum. 4th spine of 1st dorsal fin longest. No sharp distinction between sexes in pigmentation and elongation of 2nd dorsal, pelvic and anal fins. Males sometimes with 3-4 dusky vertical bars on abdomen; fully united pelvic fins with well-developed frenum; longitudinal scale series 29-32; predorsal scales 7-9, reaching interorbital space; absence of scales on cheek or opercle; depth of body 4.7-6.1 in SL Max length : 10.8 cm TL. Depth range 0 - 30 m.
Etymology
Istigobius: Greek, istios = sail + Latin, gobius = gudgeon.
Original description: Pallidogobius rigilius by Albert William Christian Theodore Herre, 1953.
Distribution
Western Pacific: Philippines and Indonesia to Kiribati and Fiji, south to Rowley Shoals in the eastern Indian Ocean and the Great Barrier Reef. Reported from the Ryukyu Islands. Reported from New Caledonia
Biology
Solitary. Occurs in sandy areas with living corals and coral rubble in clear waters. Genital papilla of male terminating to side of anal spine. Papilla of female truncate and terminating posteriorly well before origin of anal fin.
Similar species
Fishes in the genera Bathygobius can be easily confused with those of Istigobius. The main difference is the overhanging snout in Istigobius. Bathygobius has larger elongate dark spots on the midside and numerous small white spots (Istigobius has white lines, but no spots). Istigobius tends to have brighter colours, with Bathygobius being black, brown and white.
Brown-speckled sand-goby, Orange-spotted goby, Orangespotted sandgoby, Rigilius goby, Madara-kazarihaze,
Synonymes
Bikinigobius welanderi (Herre, 1953)
Istigobius rigillius (Herre, 1953)
Pallidogobius rigilius (Herre, 1953)
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Description
Dorsal spines (total): 7; Dorsal soft rays (total): 10-11; Anal spines: 1; Anal soft rays: 9 - 10; Vertebrae: 26. Upper pectoral fin rays entire. Predorsal with 7-9 cycloid scales; trunk with ctenoid scales. Segmented and non branching caudal rays 4, branching 13. Body color yellowish white; 2 brown diagonal lines from preoperculum to upper jaw, connected by a single line; 2 almost vertical brown lines on operculum. 4th spine of 1st dorsal fin longest. No sharp distinction between sexes in pigmentation and elongation of 2nd dorsal, pelvic and anal fins. Males sometimes with 3-4 dusky vertical bars on abdomen; fully united pelvic fins with well-developed frenum; longitudinal scale series 29-32; predorsal scales 7-9, reaching interorbital space; absence of scales on cheek or opercle; depth of body 4.7-6.1 in SL Max length : 10.8 cm TL. Depth range 0 - 30 m.
Etymology
Istigobius: Greek, istios = sail + Latin, gobius = gudgeon.
Original description: Pallidogobius rigilius by Albert William Christian Theodore Herre, 1953.
Distribution
Western Pacific: Philippines and Indonesia to Kiribati and Fiji, south to Rowley Shoals in the eastern Indian Ocean and the Great Barrier Reef. Reported from the Ryukyu Islands. Reported from New Caledonia
Biology
Solitary. Occurs in sandy areas with living corals and coral rubble in clear waters. Genital papilla of male terminating to side of anal spine. Papilla of female truncate and terminating posteriorly well before origin of anal fin.
Similar species
Fishes in the genera Bathygobius can be easily confused with those of Istigobius. The main difference is the overhanging snout in Istigobius. Bathygobius has larger elongate dark spots on the midside and numerous small white spots (Istigobius has white lines, but no spots). Istigobius tends to have brighter colours, with Bathygobius being black, brown and white.