Halfbarred Goby, Amblygobius semicinctus (Bennett 1833)


Summary:
A greenish to greyish-brown goby becoming paler below with a complex pattern of reddish-brown stripes along the body, the upper two converging into a dark bar through the eye onto the snout, close-set orange spots on the head, 4 to 6 narrow dark bars usually along the upper side, a dark ocellus on the first dorsal fin and on the operculum, a dark spot on the upper part of the caudal-fin base.
Females have 6-7 black-edged pale bluish-green bars along the lower side, of body between the pelvic fins and middle of the anal fin, a large dark spot in the  middle of the first dorsal fin, another spot on the upper caudal-fin base, and often 1-3 smaller spots on the caudal fin.

Cite this page as:
Bray, D.J. 2021, Amblygobius semicinctus in Fishes of Australia, accessed 29 Mar 2024, https://fishesofaustralia.net.au/home/species/5036

Halfbarred Goby, Amblygobius semicinctus (Bennett 1833)

More Info


Distribution

Cocos (Keeling) Islands in the eastern Indian Ocean. Elsewhere the species occurs in the Western Indian Ocean east to the Andaman Sea.
Inhabits sandy areas in protected bays, lagoons and estuaries, with pairs excavating burrows in the sandy/rubble substrate.

Features

Dorsal fin VI + I,14-15; Anal fin I,14-15; Pectoral fin 19-20; Lateral scale rows 54-57; Predorsal scales 22-25.  
Body moderately elongate and compressed; head slightly compressed; snout rounded, protruding beyond jaws; gill opening not extending anteriorly to a vertical line through posterior margin of preopercle; tongue rounded or near truncate. Sensory canals and pores present on head; a series of short transverse rows of sensory papillae below eye; a pair of short longitudinal sensorypapillae rows just behind chin. 
First dorsal fin with middle spines elongate and filamentous; pelvic fins united medially; frenum present. 
Scales on body ctenoid, exclusive of occipital region, nape, pectoral-fin base, belly and breast with cycloid scales; dorsal part of operculum with cycloid scales, other areas of head naked.

Size

Greyish brown, paler on abdomen, with  small blue-green spots and short lines on ventral half of head and 2 or 3 series of small whitish spots along the back; 4 or 5 narrow dark bars usually present on upper half of body; a dark brown band from front of snout to eye, continuing posterior to eye as a double band; above this on nape 3 parallel series of dark-edged orange spots (the uppermost median on nape); females  with 6 or 7 black-edged pale blue-green bars on lower part of body between pelvic fins and midbase of anal fin; a dark reddish spot as large as eye in middle of first dorsal fin and another at upper base of caudal fin (some specimens with 1-3 additional dark spots in fin).

Etymology

The specific name semicinctus is from the Latin semis (= half) and cinctum (= girdle or belt), in reference to the dark bars usually along the upper side.

Species Citation

Gobius semicinctus Bennett 1833, Proc. Zool. Soc. London 1833(1): 32. Type locality: Mauritius.

Author

Bray, D.J. 2021

Resources

Atlas of Living Australia

Halfbarred Goby, Amblygobius semicinctus (Bennett 1833)

References


Allen, G.R. & Erdmann, M.V. 2012. Reef fishes of the East Indies. Perth : Tropical Reef Research 3 vols, 1260 pp. 

Allen, G.R. & Smith-Vaniz, W.F. 1994. Fishes of Cocos (Keeling) Islands. Atoll Research Bulletin 412: 1-21 

Allen, G.R. & Steene, R.C. 1987. Reef fishes of the Indian Ocean. A pictorial guide to the common reef fishes of the Indian Ocean. Neptune City, New Jersey : T.F.H. Publications 240 pp. 

Bennett, E.T. 1833. Characters of new species from the Mauritius. Proceedings of the Zoological Society of London 1833(1): 32 

Hobbs, J-P.A., Newman, S .J., Mitsopoulos, G.E.A., Travers, M.J., Skepper, C.L., Gilligan, J.J., Allen, G.R., Choat, H.J. & Ayling, A.M. 2014. Fishes of the Cocos (Keeling) Islands: new records, community composition and biogeographic significance. Raffles Bulletin of Zoology Supplement 30: 203–219 https://lkcnhm.nus.edu.sg/rbz/supplement-no-30/

Kuiter, R.H. & Debelius, H. 2006. World Atlas of Marine Fishes. Frankfurt : IKAN-Unterwasserarchiv 720 pp. 

Kuiter R.H. & Tonozuka, T. 2001. Indonesian Reef Fishes. Part 3. Jawfishes - Sunfishes, Opistognathidae - Molidae. Melbourne : Zoonetics pp. 623–893. 

Larson, H. 2019. Amblygobius semicinctus. The IUCN Red List of Threatened Species 2019: e.T123430310A123494702. https://dx.doi.org/10.2305/IUCN.UK.2019-3.RLTS.T123430310A123494702.en. Accessed on 14 December 2021

Randall, J.E. & Goren, M. 1993. A review of the gobioid fishes of the Maldives. Ichthyological Bulletin of the J.L.B. Smith Institute, Grahamstown 58: 1-37 http://hdl.handle.net/10962/d1019911

Quick Facts


CAAB Code:37428447

Conservation:IUCN Least Concern

Depth:1-20 m

Habitat:Reef associated

Max Size:11 cm TL

Species Maps

CAAB distribution map