Largemouth Goby, Redigobius macrostoma (Günther 1861)

Other Names: Compressed Goby, Large-mouth Goby, Small-eyed Goby

A Largemouth Goby, Redigobius macrostoma, at Red Rock Estuary, Coffs Harbour, New South Wales, 12 September 2013. Source: Ian Shaw / iNaturalist.org. License: CC by Attribution-NonCommercial

Summary:

A small laterally compressed goby with a large mouth, a mottled brown body with dark lines radiating from the eyes, irregular diagonal brown bars along the sides, a bluish to blackish spot on the first dorsal fin, and oblique bands on the second dorsal fin.

Cite this page as:

Gomon, M.F. & Bray, D.J. 2021, Redigobius macrostoma in Fishes of Australia, accessed 31 Mar 2025, https://fishesofaustralia.net.au/Home/species/156

Largemouth Goby, Redigobius macrostoma (Günther 1861)

More Info

Distribution	Endemic to eastern and southeastern Australia from about Noosa, Queensland, to Port Phillip, Victoria, and the port River system adjacent to Adelaide, South Australia. Inhabits muddy and seagrass areas in estuaries, coastal lakes and the lower freshwater reaches of rivers.
Features	Dorsal fin VI + I, 7-8 (usually I, 7); Anal fin I, 5-7 (usually I,6); Caudal fin (segmented rays) 17; Pectoral fin 15-18; Pelvic fin I, 5; TRB 9-12; Vertebrae 11-12 + 14-15 = 25-27. Body deep, laterally compressed. Head of moderate size, 3.0-3.6 in SL, compressed; interorbital narrow, about equal to pupil diameter. Anterior nostril in short tube, close to edge of upper lip; mouth terminal, sometimes enlarged in males. Mouth oblique, of moderate to large size, rear end of jaws reaching to below eyes in female and young males and well beyond eyes in large males; tongue tip rounded to truncate; gill openings narrow, reaching to below middle of operculum; pectoral girdle usually smooth, occasionally with a few fleshy knobs or lobes. Body scales mostly ctenoid, lateral series 28 30; scales cycloid before first dorsal fin, operculum usually ctenoid or ctenoid dorsally and cycloid ventrally, cycloid scales on pectoral fin bases and area before ventral fins; top of head scaled forward to eyes, predorsal scales small, cycloid, 12-18. Two dorsal fins, first dorsal with rounded to triangular margin, first spine often prolonged into short filament, first dorsal originating just behind ventral fin insertions; second dorsal origin just behind first dorsal fin; anal fin origin below and just behind second dorsal origin; caudal fin with rounded margin. Pectoral fins long, reaching to above anal fin origin, margin rounded. Pelvic fins fused to form cup shaped disc, originating below pectoral fin insertions.
Size	To around 5 cm SL.
Colour	Pale brown, often translucent in life, with dark mottling dorsally; oblique dark brown bar from each eye to upper lip; second vertical bar from rear end of jaws upward to eyes, often curving backward below end of each eye to above preopercle; short horizontal dark brown bar from rear of each eye to above preopercle; lower surface of head often with two dark brown horizontal stripes; sides of body with mottling anteriorly below first dorsal fin; belly pale brown; body with five or six oblique dark brown bands from below middle of first dorsal fin to caudal peduncle, bands becoming almost vertical on caudal peduncle; base of caudal fin with two oval oblique dark brown spots; first dorsal fin grey, with large black spot posteriorly on fin; second dorsal fin with black spots forming oblique bands; anal fin grey; caudal fin with thin black wavy bands; pectoral fins clear; ventral fins clear to grey.
Biology	Likely to be oviparous, benthic spawner.
Etymology	The specific name macrostoma is from the Greek macro (= large) and stoma (= mouth) in reference to the large mouth of this species.
Species Citation	Gobius macrostoma Günther 1861, Cat Fish Brit. Mus. 3: 44. Type locality: Australia.
Author	Gomon, M.F. & Bray, D.J. 2021
Resources	Atlas of Living Australia Australian Faunal Directory Catalog of Fishes