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Tiny New Catfish Species: Freshwater Species of the Week

We’ve written before in Water Currents how scientists project that there are many species of freshwater fish yet to be described. Now, scientists have published a report in the journal Zookeys about a new species of catfish, one so tiny that it is among the smallest in the group. Scientists found it in the waters of Rio...

This tiny catfish is a new species discovered in Brazil.
This tiny catfish is a new species discovered in Brazil. Photograph by Gabriel de Souza da Costa e Silva

freshwater species of the weekWe’ve written before in Water Currents how scientists project that there are many species of freshwater fish yet to be described. Now, scientists have published a report in the journal Zookeys about a new species of catfish, one so tiny that it is among the smallest in the group.

Scientists found it in the waters of Rio Paraíba do Sul basin in Brazil, Sao Paulo State. They named it Pareiorhina hyptiorhachis, and it is a member of a genus of armored catfishes that is found only in Brazil.

From the press release, “The new species is distinguished from other species of the genus by the presence of a conspicuous ridge on the trunk posterior to the dorsal fin (postdorsal ridge).”

Pareiorhina hyptiorhachis is only about 1.2 to 1.4 inches (3 to 3.5 centimeters) in length, meaning it is smaller than many pet goldfish.

Freshwater environments across much of the world host high biological diversity, but they are also among the most threatened ecosystems. Many suffer from pollution and nutrient loading, or see their waters siphoned off.

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