Western Seacarp, Aplodactylus westralis Russell 1987

Other Names: Cockatoo Morwong, Western Australian Seacarp, Western Sea Carp

A Western Seacarp, Aplodactylus westralis, Rottnest Island, Western Australia, April 2017. Source: Alex Hoschke / iNaturalist.org. License: CC By Attribution-NonCommercial


A brown to slate-grey seacarp with six dark saddles along the upper side becoming irregular bars below, pale brown to whitish spaces between the saddles and bars, and many pale brown or whitish spots mostly on the head and unpaired fins.

Cite this page as:
Bray, D.J. 2020, Aplodactylus westralis in Fishes of Australia, accessed 02 Mar 2024, https://fishesofaustralia.net.au/home/species/1188

Western Seacarp, Aplodactylus westralis Russell 1987

More Info


Yorke Peninsula, South Australia, to Rottnest Island and just north of Perth, Western Australia. Common on rocky reefs with abundant macroalgae in depths to 20 m.


Dorsal fin XVII-XVIII, 18-19; Anal fin III, 7; Pectoral fin i, 13-14; Lateral-line scales 92-100; gill rakers 6-9 + 14-18 = 21-25; Vertebrae 16+18=34.

Body elongate, greatest depth 3.7-4.7 in SL; greatest width 5.4-7.6 in SL; head length 4.3-4.5 in SL; snout short, 2.6-2.8 in head; dorsal profile of head obtusely angled in front of eye, snout and nape subtending an angle of about 135 deg; orbital diameter 4.8-6.5 in head; interorbital space convex medially, least width of interorbital 3.6-4.5 in head; least depth of caudal peduncle 1.9± 2.4 in head; peduncle length 2.0-2.6 in head. Mouth small, somewhat ventral on head; lips fleshy, upper lip projecting, maxilla reaching a vertical through posterior nostril; teeth small, lanceolate, in 5 to 6 rows in jaws, outermost row of teeth largest; tiny crescent-shaped patch of vomerine teeth; two pairs of nostrils, anterior pair with fleshy tentaculate flaps on anteroventral margin and posteroventral margin; opercle with broad flat spine which does not extend to the fleshy margin.

Dorsal fin long-based, with elongate notch between spinous and soft parts of fin, basal length of soft dorsal fin 1.2-1.4 in length of spinous part; anal fin short, basal length 2.0-2.5 in head; pectoral fin length 1.1-1.2 in head, ventral-most 5 to 6 rays simple, fleshy; pelvic fin length 1.3-1.5 in head, rays fleshy.

Scales small, cycloid, embedded, extending on to cheeks and opercles, and forming a sheath along base of spinous dorsal fin.


Body brown or slate grey, with six dark saddles above lateral line, these giving way below to irregular bars that extend to ventral midline; interspaces between saddles and bars pale brown or whitish (some specimens with interfaces reduced or coalesced to form pale mottles); numerous pale brown or whitish spots, about diameter of pupil, mostly on head and unpaired fins.


Feeds mostly on brown algae.

Similar Species

Differs from other species of Aplodactylus in colour pattern: the Marblefish, Aplodactylus arctidens, has a reticulate pattern of pale markings on the body and fins; the Notch-head Marblefish, Aplodactylus etheridgii, has numerous small spots (less than diameter of pupil) over the entire body. The similar Rock Cale, Aplodactylus lophodon, differs in having 2-3 rows of jaw teeth (versus 5-6 rows), larger scales (lateral-line scales 72-74, versus 80 in Aplodactylus), and the lack of vomerine teeth.
Aplodactylus westralis can also be separated from other Australian species of the genus in having lanceolate teeth (vs. multicuspid teeth in A. etheridgii, and tricuspid teeth in A. arctidens), a distinctly convex interorbital space (vs. concave in A. etheridgii), and a distinctly obtuse head profile (vs. more evenly rounded in A. arctidens).


The species is named westralis in reference to its distribution in south-western Australia.

Species Citation

Aplodactylus westralis Russell 1987, Mem. Natl Mus. Vict. 48(1): 85, fig 1. Type locality: Canal Rocks, Cape Naturaliste, Western Australia (33°40'S, 115°00'E).


Bray, D.J. 2020


Atlas of Living Australia

Western Seacarp, Aplodactylus westralis Russell 1987


Burridge, C.P. 2000. Molecular phylogeny of the Aplodactylidae (Perciformes: Cirrhitoidea), a group of Southern Hemisphere marine fishes. Journal of Natural History 34(11): 2173-2185, https://doi.org/10.1080/002229300750022394

Burridge, C.P. 2000. Biogeographic history of geminate cirrhitoids (Perciformes: Cirrhitoidea) with east-west allopatric distributions across southern Australia, based on molecular data. Global Ecology and Biogeography 9(6): 517-525 https://www.jstor.org/stable/2665425

Edgar, G.J. 2008. Australian Marine Life: the plants and animals of temperate waters. Sydney : Reed New Holland 2nd edn, 624 pp.

Hoschke, A., Whisson, G. & Moore, G.I. 2019. Complete list of fishes from Rottnest Island. pp 150-161 in Whisson, G. & Hoschke, A. (eds) The Rottnest Island fish book. 2nd ed. Perth: Aqua Research and Monitoring Services.

Hutchins, J.B. 1979. A guide to the marine fishes of Rottnest Island. Creative Research, Perth. 103 pp. (as Dactylosargus arctidens)

Hutchins, J.B. 1994. A survey of the nearshore reef fish fauna of Western Australia's west and south coasts — The Leeuwin Province. Records of the Western Australian Museum, Supplement 46: 1-66 figs 1-6 

Hutchins, J.B. & Swainston, R. 1986. Sea Fishes of Southern Australia. Complete field guide for anglers and divers. Perth : Swainston Publishing 180 pp. (as Aplodactylus sp.)

Hutchins, J.B. & Thompson, M. 1983. The Marine and Estuarine Fishes of South-western Australia. Perth : Western Australian Museum 103 pp. 345 figs. (as Dactylosargus sp.)

Kuiter, R.H. 1996. Guide to sea fishes of Australia. A comprehensive reference for divers and fishermen. New Holland Publishers, Frenchs Forest, NSW, Australia., 433 pp.

Kuiter, R.H. 2000. Coastal Fishes of South-eastern Australia. Gary Allen. 437 pp.

Mees, G.F. 1960. Additions to the fish fauna of Western Australia - 2. West. Aust. Fish. Bull. 9:13-21. (as Crinodus lophodon)

Russell, B.C. 1987. New Australian fishes. Part 20. A new species of Aplodactylus (Aplodactylidae). Memoirs of the National Museum of Victoria 48(1): 85-87. https://doi.org/10.24199/j.mmv.1987.48.20

Russell, B.C. 1994. Family Aploadactylidae. pp. 642-643, figs 564-565 in Gomon, M.F., Glover, C.J.M. & Kuiter, R.H. (eds). The Fishes of Australia's South Coast. Adelaide : State Printer 992 pp. 810 figs.

Russell, B.C. 2000. Review of the southern temperate fish family Aplodactylidae (Pisces: Perciformes). Journal of Natural History 34: 2157-2171. https://doi.org/10.1080/002229300750022385

Russell, B.C. 2008. Aplodactylidae (pp. 623-624). In Gomon, M.F., Bray, D.J. & Kuiter, R.H. Fishes of Australia's Southern Coast. New Holland Publishers, Chatswood, Australia: 1-928.

Quick Facts

CAAB Code:37376004

Depth:to 20 m

Habitat:Reef associated

Max Size:35 cm SL


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