There are currently 4 described subspecies of Melanotaenia splendida. The principle differences are generally in colour, pattern and fin counts, although even these vary depending on the locality of the fish. The different forms and subspecies should not be mixed in the aquarium, as they may hybridise. Adult specimens are rarely seen for sale, and it's the much drabber juvenile fish that are almost always offered in dealers tanks. However, exercise some patience (even on a good diet, full c…

Wallago are fearsome predatory catfish that are fairly widespread in southeast Asia. There are currently five recognised species, W. attu, W. leerii, W. hexanema, W. maculatus and W. micropogon. The latter was described to science in 2004 by renowned catfish expert Heok Hee Ng and was previously considered to be a geographic variant of W. leerii. All members of the genus possess an enormous mouth full of backward pointing teeth, which are used to rip chunks from their prey. Smaller fish or amphi…

There are currently 4 described subspecies of Melanotaenia splendida, of which this species is one of the most colourful. The principle differences are generally in colour, pattern and fin counts, although even these vary depending on the locality of the fish. The different forms and subspecies should not be mixed in the aquarium, as they may hybridise. Adult specimens are rarely seen for sale, and it's the much drabber juvenile fish that are almost always offered in dealers tanks. However,…

Despite its patent unsuitability as an aquarium subject attractively-coloured juvenile specimens of this species are traded in quite large numbers, although the scarcity of privately-maintained adults would suggest that most fail to reach their potential. The striking, spotted patterning also disappears as this species matures, and since it also becomes increasingly bellligerent with age it can only be recommended to owners of the largest private aquaria or tropical ponds. There exists an albino…

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Wild populations vary in colour pattern depending on origin, and some populations have previously been described as distinct species.

A form from Peru has a particularly silvery body colour, for example, while another, marketed as ‘super red’ possesses an unusually long red stripe on the body, extending much of the length of the dark central stripe. A population from around Boa Vista in the rio Branco system, Pará state, Brazil has an ocellus o…

This species is quite rare in the aquarium hobby and is not often available in numbers, more often being exported as bycatch among shipments of the congener N. eques.

Following Weitzman and Cobb (1975) it can be diagnosed by the following combin…

There also exist a number of minor differences in colour pattern between populations. For example some Peruvian forms have yellow pigmentation on the body and fins, and those from Guyana and Suriname possess a short red stripe on vertical scale rows 6-9, above the central dark stripe on the body.

Rio Negro forms have a similar red stripe but overlapping the central dark stripe and extending along most of the flank, while a form from Colombia has an elongate red stripe which is broken in two beneath the dorsal-fi…

There are a few geographical variants of this species available, which differ in colour, patterning and less commonly, size. These should not be mixed in aquaria, as they may hybridise. The differences are so apparent between some of these forms that they may well turn out to be different species in the future….

This species has been referred to the genera Poecilobrycon and Nannobrycon in the past and in the aquarium hobby is also known as ‘rocket’, ‘brown’, ‘brown-tailed’, ‘diptail’, or ‘tubemouth’ pencilfish.It’s a popular aquarium fish and has an interesting oblique swimming-style, a behavioural trait shared only with N. unifasciatus among congeners.

In the original description the colour pattern is given by Steindachner as a brown lateral stripe exte…