After many years, we have once again received one of the most extraordinary tetras in Brazil: Moenkhausia cosmops. This species was only scientifically described in 2007. Until now it has only been known from the upper reaches of the Rio Paraguai and Rio Tapajos basins in the state of Mato Grosso: Rio Juba, Rio Juruena, Rio Papagaio and their tributaries.
The closest relatives are the aquaristically well known Moenkhausia oligolepis and M. sanctaefilomenae (redeye tetra). Other similar species are M. cotinho, M. diktyota, M. forestii and M. pyrophthalma, which have so far remained insignificant in the hobby. All these species have a red iris and the tail root spot in common. M. cosmops can be distinguished at first glance from all the other species mentioned by its unique blue-green eyes and the red stripe above the mouth.
The unique coloration of this fish is somewhat reminiscent of the wonderful emperor tetra (Nematobrycon) on the one hand and the Asian lipstick barb (Pethia erythromycter) on the other. However, there is no closer relationship to the fish mentioned.
The maximum length of Moenkhausia cosmops is around 6 cm. The fish are somewhat shy at first. They have proved to be less sensitive and peaceful with us. Like most characins, they are unproblematic in terms of diet. Stomach tests in the wild revealed insects (mainly ants), as well as plant remains and algae. The water temperature should be between 24 and 26°C, soft and slightly acidic water comes close to natural conditions, the habitats are described as white water biotopes with sandy bottoms. The species forms shoals of over 50 individuals, which are usually found near the bank vegetation between dead branches in still water zones of rivers.
For our customers: the fish has code 268643 on our stocklist. Please note that we only supply the wholesale trade.
Text and photos: Frank Schäfer