Black mudfish: Difference between revisions

The black mudfish (Neochanna diversus) is a galaxiid of the genus Neochanna, found only in swamps and wetlands in the northern half of the North Island of New Zealand, from Kaitaia in the north to the Mokau River in the south. Its length is up to 12 cm.

The distribution of the recently discovered Northland mudfish overlaps that of the black mudfish. However, the black mudfish can be distinguished from the Northland mudfish by the number of caudal fin rays; the Northland mudfish has only 13 or fewer rays whereas the other mudfish usually have 14 or more.

Black mudfish are quite abundant in the Waikato region, particularly in the Whangamarino Swamp, and they also occur on the Hauraki Plains. They have a similar life history to brown mudfish, with spawning taking place at the beginning of the wet season and probably continuing through to early spring.

Apart from land drainage and development black mudfish are also threatened by the presence of gambusia, an aggressive and prolific introduced fish that have a similar distribution pattern to black mudfish. Mudfish appear to be able to co-exist with gambusia because they can survive in habitats that periodically dry up, which gambusia cannot do, and because they breed in winter, when gambusia numbers are low.

• Froese, Rainer; Pauly, Daniel (eds.). "Neochanna diversus". FishBase. March 2006 version.
• NIWA June 2006