AAGB

Microctenopoma - a new Genus for the Bubblenesting Bushfish.

by David Armitage

There are three groups of Ctenopoma. The slim bushfish, C.pellegrini, C.nigropannosum and C.multispine form one, the remaining, deep-bodied freespawning bushfish form another and the bubblenesters form the third. Steve Norris, formerly of Arizona University, has finally taken the step of uniting the bubblenesters under a new genus on the basis of osteological characters, including details of the labyrinth organ, as well as the more obvious breeding strategy and associated sexual differences. Surprisingly, members of the new genus, Microctenopoma, are most closely related to the slim bushfish, for instance they share barred flanks, at least as juveniles and have 14 segmented caudal rays while all the other Ctenopoma have 16.

Within Microctenopoma there are two species groups, the M.nanum complex and the M.congicum complex (includingM.fasciolatum and M.pekkolai from Ethiopia) as well as two species,M.ansorgei and M.damasi that have yet to be categorised. The description of two new species and resurrection of a third, bring to 6, the number of species in the C.nanumcomplex, the others being C.milleri, with a 'chequerboard' pattern, C.intermedium from southern Africa and C.nanum, the rainforest species and the only one with solid bars on the flanks.

M.uelense Norris and Douglas
comes from Garomba National Park in the north eastern headwaters of the Zaire River and gets its name from the Uele river where most specimens were found. It has curved, mottled flanks with 8-10 indistinct bars rather than the well-defined bars of C.nanum and replaces the latter species in the non-forested regions of north-eastern Zaire basin. Specimens up to 59.5 mm were found.

M.nigricans Norris
comes from the Kasai river tributaries. Males have a black breeding colouration which gives it the specific name and which usually obscures the faint curved bars on the flanks. It grows to 68 mm.

M.ocellifer Nichols

comes from the upper Lualaba river and is named after the caudal ocellus which many of the group have as juveniles and which is retained by young adults of this species. The biggest specimen was 58 mm. It shares the nuptial colour of M.nigricans but can be distinguished by unusually high anal fin spine counts. It was originally described as a sub species of C.muriei and later synonymised with C.intermedium, thus necessitating this redescription.

Reference

1. Norris, S.M. 1995. Microtenopoma uelense and M.nigricans, a new genus and two new species of anabantid fishes from Africa. Icthyol. Explor. Freshw. 6, 357-376.

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