Tag Archives: Ntem River


New fish described from the Ntem River drainage in Cameroon, Africa

A new species of the genus Chromaphyosemion has been described by Jean-Françcois Agnèse and his co-authors in a paper* published in a recent issue of the journal Zootaxa.

The new species, who has been given the name Chromaphyosemion campomaanense, belongs to the A. calliurum species group and was collected from the the Ntem River drainage in southern Cameroon. The name campomaanense is derived from Campo Ma’an National Park, the place where the fish was found.

According to the study, Chromaphyosemion campomaanense inhabits small streams and shallow pools in the rainforest. It prefers to stay close to the river bank and stays away from deeper areas with more fast moving water.

Chromaphyosemion campomaanense differs from its close relatives by displaying an asymmetrical colour pattern on the caudal fin consisting of a yellow lower margin and a white upper margin. The body is dark blue and adorned with red spots forming horizontal rows towards the head. Posteriorly, the rows merge into vertical rows. When researchers studied the genetic make-up of this fish they found that its karyotype distinguished it from the other species of the A. calliurum species group; it was
caracterized by unusually high number of chromosomes and arms compared.

The main focus of the study was to examine the molecular phylogeny of the members of the A. calliurum species group. Using a 760 base-pair fragment of the mitochondrial cytochrome b gene, researchers found the group to be composed of 10 species:

A. ahli
A. australe
A. calliurum
A. campomaanense
A. celiae
A. edeanum
A. franzwerneri
A. heinemanni
A. lividum
A. pascheni

* Agnèse, J-F, R Brummett, P Caminade, J Catalan and E Kornobisi (2009) Genetic characterization of the Aphyosemion calliurum species group and description of a new species from this assemblage: A. campomaanense (Cyprinodontiformes: Aplocheiloidei: Nothobranchiidae) from Southern Cameroon. Zootaxa 2045, pp. 43–59.