taxonID	type	description	language	source
03EC87C8FF85FFB1FF7C98348732F997.taxon	materials_examined	Material examined: ZSI / SbRC / KN 3090, 1 ex, (TL 26.7 mm, SL 22.5 mm, BD 4.6 mm, HL 6.5 mm), Pullivasal Island, Gulf of Mannar Marine National Park (9 ° 14 ’ 55.01 ” N; 79 ° 11 ’ 3.25 ” E), 24.01.2020, Coll: Sreeraj, C. R. Diagnostic characters: Istigobius ornatus is diagnosed from congeners in having a combination of the following characters - First dorsal VI; Second dorsal I, 10; Anal I, 9; Pectoral rays 19. Upper 4 pectoral rays free. Predorsal scales 10, cycloid. Longitudinal scale series 31, ctenoid. No scales on cheek or opercle. Small fish with slender and compressed body. Dorso-laterally situated eyes. Mouth with overhanging snout, lips greatly thickened. Pale grey body colour with few (6 - 8) brownish dots forming a blotch like appearance on the operculum. First dorsal fin with yellow colour on top and brown in the middle region (colour prominent on the spines) and pale bottom. Scattered white speckles over the dorsal fins, numerous brownish-black streaks arranged in horizontal rows on side (Figure 2). Distribution: India: Andaman and Nicobar Islands, West Bengal, Andhra Pradesh, Kerala (Rajan et al., 2013; Mishra et al., 2019; Koumans, 1941) and GoM (Current Study). Elsewhere: Indo-Pacific: Red Sea South to Northern Mozambique and east to Fiji, north to southern Taiwan, south to New Caledonia and Tonga (Froese & Pauly, 2019). Remarks: Found solitary in the shallow (less than 1 m depth) silty coral reef area. As the species was found in this kind of area, live base colouration of body is light brownish and for that reason the pattern on the body is more prominent making this species well camouflaged in the environment.	en	Sreeraj, Chemmencheri Ramakrishnan (2022): First report of two gobiid fishes from the coral reefs of Gulf of Mannar, Tamil Nadu, India. Records of the Zoological Survey of India 122 (1): 51-55, DOI: 10.26515/rzsi/v122/i1/2022/157524
03EC87C8FF86FFB0FF6799468435FC42.taxon	vernacular_names	Common name - Indian silhouette goby	en	Sreeraj, Chemmencheri Ramakrishnan (2022): First report of two gobiid fishes from the coral reefs of Gulf of Mannar, Tamil Nadu, India. Records of the Zoological Survey of India 122 (1): 51-55, DOI: 10.26515/rzsi/v122/i1/2022/157524
03EC87C8FF86FFB0FF6799468435FC42.taxon	materials_examined	Material examined: ZSI / SbRC / KN 3089, 1 ex, (TL 31.8 mm, SL 24.3 mm, BD 4.5 mm, HL 10.1 mm), Pullivasal Island, Gulf of Mannar Marine National Park (9 ° 14 ’ 55.01 ” N; 79 ° 11 ’ 3.25 ” E), 24.01.2020, Coll: Sreeraj, C. R.	en	Sreeraj, Chemmencheri Ramakrishnan (2022): First report of two gobiid fishes from the coral reefs of Gulf of Mannar, Tamil Nadu, India. Records of the Zoological Survey of India 122 (1): 51-55, DOI: 10.26515/rzsi/v122/i1/2022/157524
03EC87C8FF86FFB0FF6799468435FC42.taxon	diagnosis	Diagnostic characters: Silhouettea indica is diagnosed from congeners in having a combination of the following characters - First dorsal VI; Second dorsal I, 10; Anal I, 12; Pectoral rays 15; Caudal fin rays 15. Small fish with elongated and compressed body. Depressed head with dorso-laterally situated eyes. Terminal and oblique mouth with prominent lower jaw. 2 - 3 medially placed caniniform teeth on jaws. Gill opening extending below the rear margin of preopercle. Caudal peduncle compressed and rounded caudal fin. Ctenoid scales. No scales on cheek or opercle. Light muddy coloured body with pale white ventral region, small dark brown blotches scattered above the mid dorsal as well as head region. Pale white coloured dorsal fins yellow coloured dorsally with white fin tip. Lateral rows of orange / red blotches on the dorsal fins. Caudal fin with orange and white vertical stripes and narrow white coloured fin outline, Anal fin dark brown in colour (Figure 3).	en	Sreeraj, Chemmencheri Ramakrishnan (2022): First report of two gobiid fishes from the coral reefs of Gulf of Mannar, Tamil Nadu, India. Records of the Zoological Survey of India 122 (1): 51-55, DOI: 10.26515/rzsi/v122/i1/2022/157524
03EC87C8FF86FFB0FF6799468435FC42.taxon	distribution	Distribution: India: Godavari estuary, Andhra Pradesh (Padmavathi, 2017), GoM (Present study). Elsewhere: Endemic to India.	en	Sreeraj, Chemmencheri Ramakrishnan (2022): First report of two gobiid fishes from the coral reefs of Gulf of Mannar, Tamil Nadu, India. Records of the Zoological Survey of India 122 (1): 51-55, DOI: 10.26515/rzsi/v122/i1/2022/157524
03EC87C8FF86FFB0FF6799468435FC42.taxon	discussion	Remarks: Found solitary in the shallow (less than 30 cm depth) silty coral reef area. The bend head and gape in the specimen happened due to death by asphyxiation (Figure 3). As the breakwater zone is rich in oxygen saturation, this species cannot survive in low oxygenated normal water. It is quite tough to point out the specimen in this zone and so far, no work on this genus had been done after Rao discovered it on 1971.	en	Sreeraj, Chemmencheri Ramakrishnan (2022): First report of two gobiid fishes from the coral reefs of Gulf of Mannar, Tamil Nadu, India. Records of the Zoological Survey of India 122 (1): 51-55, DOI: 10.26515/rzsi/v122/i1/2022/157524
