Warty Prowfish, Aetapcus maculatus (Günther 1861)


Other Names: Smooth Prowfish, Tasmanian Prowfish

A Warty Prowfish, Aetapcus maculatus, at Popes Eye, Port Phillip, Victoria. Source: Rick Stuart-Smith / Reef Life Survey. License: CC BY Attribution

Summary:

This curious scorpionfish relative has a compressed wedge-shaped body covered in wart-like bumps, a long-based dorsal fin attached to the caudal fin, and no pelvic fins. Warty Prowfish are often found amongst the sponges they resemble.

Juveniles are often smooth-skinned and lack the large warts seen on the head and body of adults. 

Warty prowfish lead a sedentary existence. Every few weeks they shed their skin to prevent the build-up of fouling organisms such as algae and encrusting invertebrates. At this time, the skin becomes almost transparent and water appears between the body of the fish and the skin - so much so that the fish almost looks like a balloon. When the skin finally splits, water expelled from the gills forces the skin back and the prowfish wriggles out of its old skin.

A Warty Prowfish on Fingers Reef, off Point Lonsdale, Victoria, 30 November 2014, depth 12 m.

A Warty Prowfish at Blairgowrie Pier, Port Phillip, Victoria.


Cite this page as:
Dianne J. Bray, Aetapcus maculatus in Fishes of Australia, accessed 16 Nov 2018, http://fishesofaustralia.net.au/home/species/2172

Warty Prowfish, Aetapcus maculatus (Günther 1861)

More Info


Distribution

Endemic to temperate waters of southern Australia, from Corner Inlet, Wilsons Promontory, Victoria, and northern and eastern Tasmania, to Lancelin, Western Australia, with a single record from Shark Bay.

Warty Prowfish inhabit sheltered coastal reefs, bays and harbours at depths of 1-45 m. Although usually associated with sponges, they are also found amongst seagrass and macroalgae.

Features

Dorsal-fin spines/rays XVIII-XXII, 12-13; Anal-fin rays IV-IX, 3-5; Pectoral-fin rays 8; Caudal-fin rays 9; Pelvic-fin spines/rays I, 5; Lateral line pores 8-20.

Body elongate, deep anteriorly (32-49% SL), tapering to very shallow caudal peduncle, very compressed. Head large (38-50% SL); profile of snout nearly vertical; eyes of small to moderate size (9-13% HL), positioned high on head; mouth prominent (upper jaw length 36-41% HL), oblique; teeth minute, band in each jaw;  each opercle with two low oblique ridges dorsally; head lacking sharp spines.

Scales absent, body and fins in adults covered by low fleshy bumps and wart like structures; lateral line faint, angled from upper end of each gill opening to upper surface of caudal peduncle, consisting of 8-20 indistinct, minute pores.

Segmented fin rays unbranched; fin membranes thick and fleshy. Single high long based dorsal fin with spines and rays of rather uniform length (slightly shorter near middle of fin), originating in front of eyes, continuous with basal two thirds of caudal fin; anal fin moderately long, low; caudal fin small, outer margin curved. Pectoral fins large, positioned low on body, reaching past anus, with prominent notches in posterior margin; rays thickened. Pelvic fins absent.

Size

To 22 cm SL.

Colour

Colour extremely variable, often a dirty yellow, or greyish to olive-brown, or orange to red, with darker blotches and spots. Spots small on head and body, those on dorsal and caudal fins often large, especially near fin bases.

Feeding

Carnivore - a well-camouflaged ambush predator that feeds mostly on crustaceans.

Biology

These sedentary fishes regularly shed their skin to prevent the build-up of fouling organisms. When disturbed, they may release a cloud of noxious liquid.

Remarks

As individuals grow, the skin is periodically shed intact, and is left behind resembling a ghost-like version of the prowfish.

Species Citation

Pataecus maculatus Günther 1861, Cat. Fish. Brit. Mus. 3 586: 292. Type locality: Fremantle, WA.

Author

Dianne J. Bray

Resources

Australian Faunal Directory

Warty Prowfish, Aetapcus maculatus (Günther 1861)

References


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

Edgar, G.J., Last, P.R. & Wells, M.W. 1982. Coastal Fishes of Tasmania and Bass Strait. Hobart : Cat & Fiddle Press 175 pp.

Gomon, M.F. 1994. Family Pataecidae. pp. 509-512 figs 454-456 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

Günther, A. 1861. Catalogue of the Fishes in the British Museum. Catalogue of the acanthopterygian fishes in the collection of the British Museum. London : British Museum Vol. 3 586 pp.

Johnson, J.W. 2008. Family Pataecidae. pp. 504-505 in Gomon. M.F., Bray, D.J. & Kuiter, R.H (eds). Fishes of Australia's Southern Coast. Sydney : Reed New Holland 928 pp.

Johnston, R.M. 1891. Further observations upon the fishes and fishing industries of Tasmania, together with a revised list of indigenous species. Papers and Proceedings of the Royal Society of Tasmania 1890: 22-46 (p. 33, as Pataecus armatus)

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

Kuiter, R.H. 1993. Coastal Fishes of South-eastern Australia. Bathurst : Crawford House Press 437 pp.

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.

Steindachner, F. 1883. Ichthyologische Beiträge (XIII). Anzeiger der Akademie der Wissenschaften in Wien 20(22): 194-197 (p. 195, as Pataecus vincentii - described in more detail in Steindachner, F. 1884. Ichthyologische Beiträge (13)1. Beiträge zur Kenntniss der Fische Australiens. Sitzungsberichte der Akademie der Wissenschaften. Mathematisch-Naturwissenschaftliche Classe. Wien 88(1): 1065–1108 figs 1–8

Quick Facts


CAAB Code:37292004

Biology:Regularly sheds skin

Depth:1-45 metres

Habitat:Reef associated

Max Size:22 cm SL

Native:Endemic

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CAAB distribution map