Canterbury mudfish

Species of fish

The Canterbury mudfish (Neochanna burrowsius), also known as the kowaro, is found only on the Canterbury Plains in New Zealand. Like other Neochanna species, it is a small, tubular and flexible fish which lacks scales. They are able to survive out of water in damp refuges if its wetland habitat dries out periodically over summer. The first Canterbury mudfish was described by W J Phillipps in 1926, from a specimen sent to him by Mr A. Burrows, a farmer from Oxford, North Canterbury. They were sent to him "alive in a tin box together with a quantity of damp earth, sent by parcel post on a journey lasting over thirty hours, and arrived alive and extremely active." Although Mr Burrows reported that he had found the fish aestivating in holes in the bank, the mudfish is named after the farmer rather than burrowing behaviour. Adults often grow to total length, with a maximum of at least
They are light brown or milky brown, with darker speckles that extend onto the fleshy flanges on the rear fins.

Canterbury mudfish are found from just north of Christchurch south to the Waitaki River. They currently occupy springs, water races, and drains, but previously would have inhabited the abundant wetlands of the Canterbury Plains, before these were drained for farming. As their wetland habitat dries out, the water may become stagnant and low in oxygen. When the dissolved oxygen saturation of the water reaches 15–30% Canterbury mudfish begin 'air breathing', in which they take a bubble of air into the mouth and absorb oxygen from it. Also in 2014 the IUCN rated the Canterbury mudfish as "Critically endangered".