Spiny Boxfish, Capropygia unistriata (Kaup 1855)

Other Names: Black-banded Pigmy Boxfish

A Spiny Boxfish, Capropygia unistriata, from Port Phillip, Victoria, June 2023 - photographed in an aquarium. Source: Rudie Kuiter / Aquatic Photographics. License: All rights reserved

A pale yellowish-brown to tan or greyish-brown boxfish, usually with a broad black stripe along the side (may be indistinct in some individuals), black lips, and the ridge spines and fin bases with black blotches or encircled with black.

Cite this page as:
Bray, D.J. 2023, Capropygia unistriata in Fishes of Australia, accessed 16 Apr 2024, https://fishesofaustralia.net.au/home/species/835

Spiny Boxfish, Capropygia unistriata (Kaup 1855)

More Info


Endemic to southern Australia from Bass Strait (about Cape Conran), Victoria, to north of Rottnest Island, Western Australia. Although the species is known mostly from specimens taken as bycatch in commercial trawl fisheries, individuals occasionally wash ashore after storms.
Mostly inhabits deeper reefs on the continental shelf.


Dorsal fin 12; Anal fin 12-13; Caudal fin 10-11; Pectoral fin 11-12. 
Body short, circular in profile, very deep, somewhat hexagonal in cross section; pronounced keel like ridges on dorsal and ventral midlines, especially dorsally; each side with distinct longitudinal ridge ventro-laterally with prominent flattened curved spine posteriorly and similar ridge dorso-laterally with prominent centrally placed spine. Head moderately small, dorsal profile straight; eyes small, high on head, directed antero-laterally; mouth small, terminal, with fleshy lips; teeth long, curved, close set, single row in each jaw; gill opening on each side in form of short vertical slit just in front of pectoral fin base.  
Scales large, hexagonal, fused into rigid bony carapace, covering body in front of dorsal and anal fins, centre of each individual plate with very low tubercle and radiating rows of finer tubercles connecting adjoining plates; caudal peduncle with complete bony ring at base of tail and bony plate on dorsal and ventral surfaces anteriorly, plates covered with rough tubercles. 
Single dorsal fin small, short-based, fan like, positioned posteriorly on body, its length about equal to depth of caudal fin base; anal fin identical to and opposite dorsal fin; caudal fin rounded. Pectoral fins small, fan like. Pelvic fins absent.


The specific name unistriata is from the Latin uni- (= one) and striatus (= striped) in reference to the distinctive black stripe along the side.

Species Citation

Acerana (Capropygia) unistriata Kaup, 1855, Arch. Naturgesch. 21(1): 220. Type locality unknown.


Bray, D.J. 2023


Atlas of Living Australia

Spiny Boxfish, Capropygia unistriata (Kaup 1855)


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, Western Australia.

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

Kaup, J.J. 1855. Uebersicht über die Species einiger Familien der Sclerodermen. Archiv für Naturgeschichte 21(1): 215-233. See ref at BHL

Kuiter, R.H. 1994. Family Aracanidae. pp. 892-902, figs 788-794 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.

Matsuura, K. 2008. Families Ostraciidae, Tetraodontidae. pp. 842-856 in Gomon, M.F., Bray, D.J. & Kuiter, R.H. (eds). Fishes of Australia's Southern Coast. Sydney : Reed New Holland 928 pp.

Matsuura, K., Amaoka, K. & Carpenter, K.E. 2020. Capropygia unistriata. The IUCN Red List of Threatened Species 2020: e.T162918363A162918382. https://dx.doi.org/10.2305/IUCN.UK.2020-1.RLTS.T162918363A162918382.en. Accessed on 15 June 2023.

May, J.L. & Maxwell, J.G.H. 1986. Field Guide to Trawl Fish from Temperate Waters of Australia. Hobart : CSIRO Division of Marine Research 492 pp.

McCulloch, A.R. & Waite, E.R. 1915. A revision of the genus Aracana and its allies. Transactions of the Royal Society of South Australia 39: 477-493 pls 16-25 See ref at BHL

Scott, T.D., Glover, C.J.M. & Southcott, R.V. 1974. The Marine and Freshwater Fishes of South Australia. Adelaide : Government Printer 392 pp. figs.

Waite, E.R. 1921. Illustrated catalogue of the fishes of South Australia. Records of the South Australian Museum (Adelaide) 2(1): 1-208 293 figs pl. 1 See ref at BHL

Williams, A., Last, P.R., Gomon, M.F. & Paxton, J.R. 1996. Species composition and checklist of the demersal ichthyofauna of the continental slope off Western Australia (20–35º). Records of the Western Australian Museum 18: 135-155 See ref online

Quick Facts

CAAB Code:37466011

Conservation:IUCN Least Concern

Depth:10-200 m

Habitat:Reef associated

Max Size:12 cm TL


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CAAB distribution map