Clarence River Cod, Maccullochella ikei Rowland 1986
A Clarence River Cod, Maccullochella ikei, in northern New South Wales, April 2019. Source: Brett Vercoe / iNaturalist.org. License: CC By Attribution-NonCommercial
A large olive to yellowish-green or golden cod, with a concave forehead profile, pelvic-fin rays with elongate filaments, distinct reticulated mottling on the head and body; belly whitish.
Video of a Clarence River Cod amongst snags in the wild (also called the Eastern Freshwater Cod).
Clarence River Cod, Maccullochella ikei Rowland 1986
More Info
Distribution |
Historically endemic to and widely distributed in the Clarence,
Richmond and Brisbane River systems of coastal north-eastern New South
Wales and southern Queensland. The species is now thought to only exist naturally in the Clarence River System. Inhabits pristine sections of clear, flowing, freshwater rocky streams with plenty of logs, woody debris and other in-stream cover. |
Features |
Dorsal fin X-XII, 13-16; Anal fin III, 11-12; Pectoral fin 16-19; Lateral line distinct with 65-82 scales; 32-52 scale rows below lateral line. Body relatively deep, and elongate, moderately compressed; greatest body depth 26.0-30.3% SL; depth of caudal peduncle 10.7-12.5% SL; head broad, width 46.0-66.2% HL; slope of head profile concave; mouth large reaching back to rear edge of eye; upper jaw protrudes over lower; eyes moderately large, eye diameter 12.0-19.0% HL; jaws, vomer and palatines with irregular rows of villiform, curved teeth; operculum with fleshy margin and 2 spines. Scales small, mostly ctenoid, present on cheeks and operculum scaled, snout naked. Dorsal fin origin behind pectoral and ventral fin bases; dorsal spines strong, soft dorsal rounded; anal fin rounded, opposite soft dorsal; pectoral fin large, upper rays longest; ventral fin inserted forward of pectoral fin base, 1st ray elongated into 2 filaments, 2nd long, tapering to a fine tip; caudal fin large, rounded. |
Size |
To at least 66 cm SL and 41 kg. |
Colour |
Olive-green to yellowish with dark mottling on back, head, sides and bases of median fins; white ventrally; median fins with white edges. |
Feeding |
Feeds on fishes, crustaceans, molluscs, amphibians, aquatic birds and the occasional reptile. |
Biology |
Spawns in spring when water temperatures exceed 16°C; breeding season is short lasting only 8-10 weeks. Nest sites are vigorously cleaned by males until the day of spawning when females enter the site and a complex courting ritual to facilitate spawning occurs. Males guard and fan the eggs until hatching and then vigorously defend the larvae up until 12-14 days post-hatch when larvae disperse from the nest site. |
Fisheries |
This species is protected making it illegal to target while fishing. |
Conservation |
IUCN Red List: Endangered. EPBC Act: Endangered. |
Remarks |
Overfishing and habitat destruction during railroad construction, mining, agriculture and heavy flooding following a bushfire event have all been attributed to causing the decline of this species. |
Similar Species |
Differs from Maccullochella peelii in having longer pelvic fins, a larger orbit diameter, larger and morphologically distinct sagittal otoliths, and a distinctive colour pattern. Differs from Maccullochella mariensis in having a narrower caudal peduncle, a shorter post-orbital head length, a larger orbit, shorter inter-orbital width, more scale rows below the lateral line, longer fifth and sixth dorsal-fin spines, and a greater extension of the first anal-fin pterygiophore towards the vertebral column. Differs from Maccullochella macquariensis in having a concave head profile, a protruding lower jaw, 15 precaudal vertebrae, a greater extension of the first anal pterygiophore towards the vertebral column, and a distinctive coloration. |
Etymology |
Stuart Rowland named the species ikei after his late grandfather, Isaac (Ike) Morgan Rowland, a great admirer and angler of Australian native inland fishes, particularly the Murray cod. |
Species Citation |
Maccullochella ikei Rowland 1986, Biennial Report, July 1983–June 1985. Agricultural Research and Advisory Station, Grafton. Department of Agriculture, N.S.W. : 16. Type locality: Nymboida River, junction with Mann River, 29°39'S, 152°30'E, New South Wales. |
Author |
Bray, D.J. & Thompson, V.J. 2021 |
Resources |
Clarence River Cod, Maccullochella ikei Rowland 1986
References
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