Studies on African Characid Fishes I. The tribe Alestidi (I)

Among a recent importation from the Belgian Congo there was a multitude of lovely little aquariumfishes, mostly well-known to aquarists. but partly new to them, and some of these fishes even new to science. A large number of small ”Tetra’s” closely resembled the well-known species Petersius caudalis. Four perfectly preserved specimens (formol), were supplied to me by Mr. C. A. Spoelstra of Haarlem, a well-known aquarist-breeder. In order to identify this species, and designate its proper place, I started to study literature and material in the Museum. It then became evident that the classification and nomenclature of this group is far behind, a case somewhat similar to the one I recently discussed concerning the South-American Nannostomidi (Hoedeman, 1950 : 11-271). A large number of forms, merely of subspecific rank or local varieties only, have been named and classified as good species, while too much stress has been laid upon the dentition and number of rows of teeth as a character in the classification of this group. This character now clearly is of polyphyletic nature, and even highly variable in species and subspecies.