Southern Sand Flathead, Platycephalus bassensis Cuvier 1829


Other Names: Bass Flathead, Bay Flathead, Common Flathead, Sand Flathead, Sandy, Sandy Flathead, Slimy Flathead, Yanks

A Southern Sand Flathead, Platycephalus bassensis, in Port Phillip, Victoria. Source: Rudie H. Kuiter / Aquatic Photographics. License: All rights reserved

Summary:

A sandy to pale brownish flathead peppered with small pale to dark spots, 2-3 indistinct bands along the back towards the rear of the body, and a whitish belly. The lower half of tail has a large dark irregular blotch, often broken up by the pale fin rays, and the upper half is covered in large brown spot or blotches. The head has two large strong spines at the corner of the gill cover, and the lower is much longer than the upper spine.



Cite this page as:
Australian National Fish Collection & Bray, D.J. 2018, Platycephalus bassensis in Fishes of Australia, accessed 15 Nov 2018, http://fishesofaustralia.net.au/home/species/3356

Southern Sand Flathead, Platycephalus bassensis Cuvier 1829

More Info


Distribution

Endemic to coastal waters of southern Australia from off Red Rock, New South Wales, to west of Cape Adieu, Great Australian Bight, South Australia and around Tasmania.

The Southern Sand Flathead inhabits sandy, muddy or shelly bottoms in shallow coastal bays to depths of about 100 m.

Features

Dorsal fin VIII-IX, 13 or 14 (usually 14); Anal fin 14; Caudal fin 15; Pectoral fin 19 or 20 (rarely 18 or 21); Pelvic fin I, 5; Lateral line scales (pored) 71-82; Gill rakers 18-20.

Body elongate, slightly depressed. Head large (length 29-31% SL), depressed, with two strong bony ridges behind eye; eyes moderately large (16-23% HL) with small iris lappet; mouth large with small pointed teeth on jaws, in a broad patch on vomer and a narrow band on palatines, no enlarged canines; two strong preopercular spines at angle of preopercle, lower about twice length of upper; gill rakers on lower limb of first arch long and slender; interopercular flap absent.

Scales small, finely ctenoid, covering body and most of head behind eyes; lateral line scales slightly larger than adjacent scales on side, ~100 oblique rows of scales above lateral line, anteriormost one or two scales with small spine or ridge. Swim bladder absent.

First dorsal fin spinous with short base, first spine very short, detached, following spines much longer. Second dorsal fin with moderately long base, anterior rays longest, subequal in length to 4th or 5th first dorsal fin spines. Anal fin similar in shape, opposite and slightly longer-based than second dorsal fin. Caudal fin truncate. Pectoral fins moderately small. Pelvic fins long, based below centre of pectoral fins.

Size

Maximum length at least 55 cm TL; maximum weight at least 1.3 kg.

Colour

Sandy brown above with discrete, widely-space, reddish brown flecks, dark blotches sometimes along midline of sides, indistinct dark brown bands posteriorly; pale to whitish ventrally.

Caudal-fin lower half white with one (sometimes 2) large, blackish blotches posteriorly which are sometimes broken into segments by pale rays, upper half with large brownish blotches; other fins with small dusky to dark spots.

Feeding

Carnivore - feeds mostly on fishes and also on large benthic crustaceans. This ambush predator hides from its prey by burying itself in the sediment.

Biology

The sexes are separate, fertilisation is external. Females spawn from late winter to December, and eggs and larvae are pelagic.

Flathead larvae have large, wide heads with extensive spination, moderate to large fan-shaped pectoral fins and 26–28 myomeres.

Larvae of P. bassensis are distinguished from both Platycephalus fuscus and P. speculator by the larger size at both notochord flexion (6.0– >8.4 mm) and pelvic (5.9–7.4 mm) and dorsal fin (6.2–>8.4 mm) formation. In addition, the trunk and tail are only lightly pigmented in P. bassensis larvae, which contrasts with moderate to heavy pigment in larval P. fuscus and P. speculator (Jordan 2001).

After settling to the bottom, the larvae grow rapidly for the first 3 years, reaching a total length of 22-25 cm.

Fisheries

Taken in moderate numbers by commercial trawlers and Danish seiners offshore and also by gillnet, beach seine and hook and line inshore.

The Southern Sand Flathead is a very popular recreational fish in Victoria and Tasmania, and large numbers are taken on hook and line in estuarine and sheltered inshore waters.

The species accounted for over 90% of the recreational catch of flathead in Tasmania during 2000–01, with an estimated 1.2 million fish retained and 0.7 million (36% of total catch) released (Lyle 2005).

Remarks

Records further west of the Great Australia Bight are misidentifications of Platycephalus westraliae (Imamura 2015).

Species Citation

Platycephalus bassensis Cuvier, 1829, in Cuvier & Valenciennes, Hist. nat. Poiss. 4: 247, Western Port, Victoria.

Author

Australian National Fish Collection & Bray, D.J. 2018

Resources

Australian Faunal Directory

Southern Sand Flathead, Platycephalus bassensis Cuvier 1829

References


Bani, A., N. Moltschaniwskyj & N. Pankhurst. 2009. Reproductive strategy and spawning activity of sand flathead, Platycephalus bassensis (Platycephalidae). Cybium 33(2): 151-162.

Brown, I.W. 1977. Ecology of three sympatric flatheads (Platycephalidae) in Port Phillip Bay, Victoria. Monash University, Victoria. Ph.D. dissertation. 324 pp.

Coleman, N. 1980. Australian Sea Fishes South of 30ºS. Lane Cove, NSW : Doubleday Australia Pty Ltd 309 pp. 

Cuvier, G.L. in Cuvier, G.L. & Valenciennes, A. 1829. Histoire Naturelle des Poissons. Paris : Levrault Vol. 4 518 pp. pls 72-99. 

Gomon, M.F. 2008. Family Platycephalidae. pp. 515-521 in Gomon, M.F., Bray, D.J. & Kuiter, R.H. (eds). Fishes of Australia's Southern Coast. Sydney : Reed New Holland 928 pp.

Gomon, M.F. & P.R. Last. 2008. Family Platycephalidae. Pp. 515-521. In: Gomon, M.F., D.J. Bray & R.H. Kuiter. Fishes of Australia's Southern Coast. Reed New Holland, Chatswood, Australia, 928 pp.

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

Imamura, H. 1996. Phylogeny of the family Platycephalidae and related taxa (Pisces: Scorpaeniformes). Species Diversity 1(2): 123-233

Imamura, H. 2006. Rediagnosis of the marbled flathead, Platycephalus marmoratus (Actinopterygii: Teleostei: Platycephalidae), with comments on the composition of the type series. Species Diversity 11: 295-306.

Imamura, H. 2008. Synonymy of two species of the genus Platycephalus and validity of Platycephalus westraliae (Teleostei: Platycephalidae). Zoological Research 55: 399-406 

Imamura, H. 2015. Taxonomic revision of the flathead fish genus Platycephalus Bloch, 1785 (Teleostei: Platycephalidae) from Australia, with description of a new species. Zootaxa 3904(2): 151–207 

Jordan, A.R. 2001. Reproductive biology, early life-history and settlement distribution of sand flathead (Platycephalus bassensis) in Tasmania. Marine and Freshwater Research 52(4): 589-601

Kailola, P.J., Williams, M.J., Stewart, P.C., Reichelt, R.E., McNee, A. & Grieve, C. 1993. Australian Fisheries Resources. Canberra : Bureau of Resource Sciences and the Fisheries Research and Development Corporation 422 pp.

Keenan, C.P. 1991. Phylogeny of Australian species of flatheads (Teleostei, Platycephalidae) as determined by allozyme electrophoresis. Journal of Fish Biology 39 (Supplement A): 237-249 

Kuiter, R.H. 1994. Family Platycephalidae. pp. 514-523 figs 458-465 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. 

Kuiter, R.H. 1996. Guide to Sea Fishes of Australia. A comprehensive reference for divers and fishermen. Sydney, NSW, Australia : New Holland Publishers xvii, 434 pp.

Lyle, J.M. 2005. 2000/01 Survey of Recreational Fishing in Tasmania. Technical Report Series No. 24. (Tasmanian Aquaculture and Fisheries Institute: Hobart.)

Lyle, J.M., Moltschaniwskyj, N.A., Morton, A.J., Brown, I.W. & Mayer, D. 2007. Effects of hooking damage and hook type on post-release survival of sand flathead (Platycephalus bassensis). Marine and Freshwater Research 58: 445–453.

May, J.L. & J.G.H. Maxwell. 1986. Trawl fish from temperate waters of Australia. CSIRO Division of Fisheries Research, Tasmania. 492 pp.

Richardson, J. 1842. Descriptions of Australian fish. Part 1. Transactions of the Zoological Society of London 3(1): 69-131 figs 4-6

Whitley, G.P. 1931. New names for Australian fishes. The Australian Zoologist 6(4): 310-334 1 fig. pls 25-27 

Whitley, G.P. 1938. Studies in Ichthyology No. 11. Records of the Australian Museum 20(3): 195-199 fig. 1 pl. 21 

Whitley, G.P. 1951. Flatheads. Australian Museum Magazine 10(8): 244-248

Yanase, K. & Arimoto, T. 2007. A hydro-mechanical approach to the scaling of swimming performance in the sand flathead Platycephalus bassensis Cuvier: effects of changes in morphological features based on fish size. Journal of Fish Biology 71: 1751–1772.

Yearsley, G.K., Last, P.R. & Ward, R.D. (eds) 1999. Australian Seafood Handbook. Hobart : CSIRO Marine Research 460 pp.

Quick Facts


CAAB Code:37296003

Danger:Venomous spines

Depth:1-100 m

Fishing:Commercial, recreational

Habitat:Sandy, muddy bottom

Max Size:55 cm TL; 1.3 kg

Native:Endemic

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