Moenkhausia costae (Steindachner, 1907)

An ubiquitous species in the middle stream of the Rio São Francisco

I could collect Moenkhausia costae frequently during my trips in to the Rio São Francisco basin - in the middle stream of the river it is almost ubiquitous. It seems to attain around 40 mm SL and is rather conspicious carrying a diagonal black stripe. The stripe seems to serve a signal for communication among the swarm members. I caught them in limnic waters - during the dry season some of them were rest waters of rivers. The water types were different; some habitats possessed cloudy and muddy white waters while others were highly transparent. Such a cloudy white water habitat was E-BR 32-07, located southern of Bom Jesus da Lapa on the right bank of the river. The picture below shows Moenkhausia costae in this habitat’s white water.

This is Moenkhausia costae (below) caught in a clear water habitat close to Brasilandia de Minas on the river’s left bank. It was a huge area flooded by the Rio Paracatu which is also a tributary to the mighty Rio São Francisco. 

Another example; Moenkhausia costae (below) caught in cloudy white water syntop with others Characids, Corydoras and Pimelodus nearby Malhada on the Rio’s right bank.

I wonder why Moenkhausia costae is not really present in our fish tanks since it possesses an attractive color pattern and does not seem to be tricky in aquarium maintenance. SCHAEFER (2007) reports that it has been imported to Europe.

Marco Endruweit, December 2007