Anyone who has ever dealt with piranhas and their species identification knows that it is difficult! Piranhas change their coloration significantly over the course of their lives, and in many cases, this coloration also varies individually. The body shape is also subject to ontogenetic changes (ontogenesis: individual development, as opposed to phylogenesis, the phylogenetic, genetically determined development). That is why the history of research on piranhas is full of errors. This applies both to scientific research and, to an even greater extent, to aquarium research. Every new publication brings new insights. And it seems that the description of a new piranha species (Serrasalmus magallanesi) from the upper Rio Madeira system in Bolivia has brought with it the clarification of an old error.
Serrasalmus hollandi is a well-known species that was first described in 1915 from the Rio Guaporé near the city of Maciél in Brazil. The Rio Guaporé is known to be the border river between Brazil and Bolivia (where it is called Rio Iténez), so the first describers also had to redefine S. hollandi in order to distinguish their new species from the well-known one.
In aquariums, several piranha species have been identified as S. hollandi: erroneously, it seems. The “real” S. hollandi is a blunt-snouted piranha that is extremely similar to S. humeralis, S. eigenmanni, and S. serrulatus, and some age classes of S. gouldingi also look very similar. Based on the latest findings, it can be assumed that all piranhas from Peru previously referred to as “S. eigenmanni” are actually S. hollandi. S. eigenmanni is only found in Guyana.
Serrasalmus hollandi reaches a body length of around 20 cm. The species is considered a specialized fin eater, which means it is difficult to keep in groups, as even conspecifics are generally regarded as a food source. Since such piranhas are only kept by specialists and research institutions, further information on keeping them in aquariums is unnecessary at this point.
For our customers: S. hollandi has code 292200 (2-3 cm) to 292205 (12-15 cm) on our stock list. Animals currently imported from Peru are listed under “cf. hollandi” with the code numbers 292212 (4-6 cm) and 292213 (7-10 cm). Please note that we only supply wholesale customers.
Literature:
Gallo-Cardozo, F., M. Maldonado, M. Careaga & F. M. Carvajal-Vallejos (2024): A new species of Piranha (Serrasalmus, Serrasalmidae) from the upper Madeira River system, Amazon basin, Bolivia. Journal of Ichthyology v. 64 (no. 3): 386-409
Text & photos: Frank Schäfer
