Northern bastard codling

Pseudophycis breviuscula falls under the ray-finned fish class Actinopterygii. The order Gadiformes represents all cods (both marine, freshwater, and bracken) while the family Moridae is a collection of marine only cod-like fish. In the genus Pseudophycis (of which are only found in Southern Australia and/or New Zealand) there are two other species. Pseudophycis barbata (Southern bastard cod) and Pseudophycis bachus (red codling) complete this genus with P. breviuscula.

P. breviuscula is the smallest of the red cods with maximum size thought to be approximately 250mm. Other red cods can reach lengths up to 900mm. It was previously confused with P. barbata for some years. It can be identified as separate to P. bachus by the lack of presence of a dark spot near the bottom of the pectoral fin and displays larger scales than the southern bastard cod. It has two dorsal fins; the anterior being quite short while the posterior dorsal fin stretches more than half the body length. The caudal (tail) fin is rounded and not overly wide. The ventral aspect of the body is described as silver in color while the dorsal section is a pale pink-brownish color. The eyes are large and a barbel is present on the chin.

P. breviuscula is described as a ‘cryptic fish’ in that its behavior and habitat makes its difficult to study and accurately detect. Cryptic species are often seen to be endemic species. P. breviuscula is endemic New Zealand reef fish that occupies a temperate water climate. It is known to be nocturnal which is likely one of the reasons very little study has been done on it. The only New Zealand recordings of the northern bastard cod are in the North Island. It is more often recorded seen on the eastern coast than the western.

While very little known is known about the northern bastard cod, a survey conducted on the inhabitants of the north-east coastal reef fish was performed providing some insight to the diet of P. breviuscula. The survey showed it to be a carnivorous benthic feeder of small crustaceans such as amphipods, shrimps, and crabs. This was done via examination of stomach contents. Feeding behavior could not be observed due to the nocturnal nature of this fish.

• Froese, Rainer; Pauly, Daniel (eds.) (2006). "Pseudophycis breviuscula" in FishBase. March 2006 version.
• Tony Ayling & Geoffrey Cox, Collins Guide to the Sea Fishes of New Zealand, (William Collins Publishers Ltd, Auckland, New Zealand 1982) ISBN 0-00-216987-8
• http://www.fishbase.de/Summary/speciesSummary.php?ID=2022&AT=Northern+bastard+cod , retrieved 4 March 2015.
• http://www.fishbase.org/Summary/FamilySummary.php?Family=Moridae , retrieved 4 March 2015.
• Willis, T.J. & Anderson, M., (2003), Structure of cryptic fish assemblages: relationships with habitat characteristics and predator density, Marine Ecology Progress Series, Vol. 257, 209-221.
• Russell, B.C., (1983), The food and feeding habits of rocky reef fish of north eastern New Zealand, New Zealand Journal of Marine and Freshwater Research, 17:2, 121-145.
• Paulin, C.D. & Roberts, C.D., (1992), The rockpool fishes of New Zealand, Colourcraft Ltd, Hong Kong.