Melanotaenia parkinsoni is one of the few species of rainbowfish that are offered relatively regularly in the trade. The home of this maximum 14 cm long, but usually much smaller animal is in Papua New Guinea, in the Central Province. There are only confirmed specimens from the Kemp Welsh River, which is sometimes also referred to as the Wanigela River. The species was first collected in 1978 by Gerald Allen, who described it scientifically in 1980.
They are very similar to other rainbowfish species, which makes it very difficult to identify specimens from the pet trade (where the natural origin is unknown). The population originally collected by Allen, from which the majority of the animals living in aquariums around the world today probably originate, differs from all other species by its single-colored orange or yellow fins in combination with a dark border. There are yellow or orange horizontal stripes on the posterior body. In males, these stripes can merge to form large patches, which also only occurs in M. parkinsoni. Otherwise, the species is very similar to the widespread and extremely variable M. rubrostriata, but does not become as high-backed as the latter in old age.
In the hobby there is a color variant that is bright red instead of yellow/orange. As far as we know, this is a morph created by selection breeding. For some time now, however, there have also been morphs in which the differences to M. rubrostriata are very indistinct. Sometimes these animals show the plain yellow fins that are so typical of M. parkinsoni, but some also show a dot pattern in the fins on a blue or blue-green background, as is known from M. rubrostriata; all these colours appear within a batch.
As far as we know, only offspring of M. parkinsoni are available in the trade. We do not know whether the animals with the spotted fins are descendants of a more recent collection, a mutation or hybrids. As many rainbowfish species interbreed in the aquarium, it is the breeder’s responsibility to keep only one species in the breeding aquarium at any one time. Otherwise a mishmash can occur and the species may be lost to the hobby for a long time.
For our customers: M. parkinsoni has code 428503 on our stocklist. Please note that we only supply the wholesale trade.
Text & photos: Frank Schäfer
