Russian scientists have described two new species of fish in the Caspian Sea basin: the Caspian puggolovochka (Benthophiloides caspicus), found off the coast of Kazakhstan, and the Scythian goby (Proterorhinus scythicus), found in the Eastern Manich River and the Volga Delta.
The study was carried out by specialists from Russian scientific institutions during several expeditions between 2021 and 2025 and was supported by a grant from the
Russian Foundation for Science.
To identify the species, the scientists combined genetic and morphological analyses. Analysis of the COI gene, used as a genetic “barcode”, confirmed that the specimens belonged to distinct evolutionary lineages.
The Caspian puggolovochka was found in the eastern Caspian Sea, off the coast of Kazakhstan. The specimen was recovered from the mouth of a water snake that had captured it. The species is extremely rare, and only two specimens are currently known. Its genetic characteristics reflect a long evolutionary history of gobies in the Caspian Sea.
The Scythian goby was found in the Volga Delta and in the Eastern Manich River in Kalmykia. Analyses showed greater evolutionary proximity to gobies from the Black Sea basin than to those from the Caspian Sea. The researchers link this pattern to an ancient connection between the two seas, which existed around 2.1 million years ago.
“Accurate assessment of species diversity is a prerequisite for effective nature conservation, particularly against a backdrop of rapid climate change and increasing human pressure on ecosystems,” said Boris Lyovin, the project leader.
Scientists hope that further studies of the Black, Azov and Caspian Seas will lead to the discovery of other species and a better understanding of the evolution of their ecosystems.
Scientific research into biodiversity is also advancing in the BRICS member countries, where new species have been discovered in freshwater and marine ecosystems.
For example, in China, researchers from Jishou University and the Zhangjiajie Giant Salamander National Nature Reserve identified a new species of freshwater fish in Hunan province. Acrossocheilus zhangjiajiensis was found in streams in the upper reaches of the Lishui River during research and monitoring work carried out since 2021.
According to
China Daily, a partner of TV BRICS, the scientists used morphological analyses and molecular biology studies to determine that the fish exhibited significant differences from all known species of the genus Acrossocheilus. With this discovery, the number of valid species of the genus worldwide has reached 25. These small fish typically inhabit clear-water, fast-flowing mountain streams and are of ecological and economic importance in China and South-East Asia.
Beyond the BRICS countries, in Argentina, specialists from the National Scientific and Technical Research Council (CONICET) and other scientific institutions have described Characidium lilloi, a new species of fish found exclusively in the mountain rivers and streams of the north-west of the country.
According to
CONICET, the species was found in the upper catchment areas of the Bermejo and Juramento rivers, in the provinces of Salta and Jujuy. The researchers combined morphological and osteological studies with DNA analysis to confirm its distinct status. The discovery expands our knowledge of one of the Argentine regions with the greatest diversity and endemism of freshwater fish.