London: Scientists have discovered a tiny new species of catfish, measuring only about 3 cm in length, in Brazil.
The new species Pareiorhina hyptiorhachis, found in the waters of Rio Paraiba do Sul basin, belongs to a genus of armoured catfishes native to South America.
These fish get their name from their strange elongated mouth barbels that remind of cat`s whiskers.
The new species is distinguished from others 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 3-3.5 cm in length, making it one of the smallest representatives of the catfish order.
Although the new species is only the size of a decorative fish, there are even smaller representatives in the group. Some of the smallest species of Aspredinidae and Trichomycteridae for example reach sexual maturity at only 1 cm in total.
On the other side of the scale is the wels catfish whose representatives can reach more than 2.5 metres (8.2 ft) in length and sometimes exceeded 100 kilogrammes.
This fish has also been recorded to feed on frogs, rats, mice and even some aquatic birds. Many of the large catfish species are farmed or fished for food thus being of significant scientific importance.
Small representatives, on the other hand, are often used as aquarium decorative fish.
The discovery was published in the journal Zookeys.