New species of caatinga fish is named after Lula – 10/20/2023 – Science

Researchers from UFRN (Federal University of Rio Grande do Norte), UFPB (Federal University of Paraíba) and Instituto Peixes da caatinga, among others, discovered a new species of fish from the Caatinga in the municipality of Lagoa Salgada (about 70 km from Natal ).

The name of the new species, Hypsolebias lulaihonors President Luiz Inácio Lula da Silva.

Popularly known as cloud fish, the genus Hypsolebias it has 34 species (35 with the new discovery), belonging to the Rivulidade family, order Cyprinodontiformes, with neotropical distribution (in the Americas). The group represents the most endangered fish in Brazil, due to its endemic nature (restricted to a single environment) of temporary lagoons in the caatinga.

As research published by the Sheet this week, the caatinga is the most threatened biome in Brazil and could have up to 90% of its diversity threatened by 2060.

For this reason, the scientists responsible for the study decided to honor Lula to raise awareness about the importance of preserving H. lulai and other species found in the country. Furthermore, they wanted to draw attention to the promised resumption of investment in science in Lula’s third term, after a period of cuts during the Bolsonaro administration.

The article describing the find was published this Friday (20) in the journal Neotropical Ichthyology. Participating in the study are Telton Ramos and Fábio Origuela, from the Peixes da Caatinga Institute, Yuri Abrantes, from UFRN, Dalton Nielsen, from the Zoology Laboratory at the University of Taubaté, and Silvia Lustosa-Costa, from the Aquatic Ecology Laboratory at UFPB.

O H. lulai It has a very characteristic color: the male has stripes and a bluish band on the dorsal part, while the females are smaller and have a brownish color. The total size of the animal is 5 cm, with some individuals reaching 6 cm in length.

The fish of the genus Hypsolebias They feed on small invertebrates, such as insect larvae and other arthropods, and occasionally small vertebrates, such as tadpoles. They live in temporary lagoons that appear in the middle of the caatinga hinterland, mainly in the states of Paraíba, Rio Grande do Norte, Ceará, Tocantins and Piauí. They were already known for the São Francisco and Tocantins-Araguaia river basins, but this is the first time they have been found in the Trairi river basin.

Another species, Hypsolebias longignatuswhich occurs in the Pacoti river basin, in Ceará, is considered the closest to H. lulai.

According to Telton Ramos, who is also a postdoctoral fellow in the biological sciences program at UFPB and first author of the study, it was surprising to discover the new fish in the region, since its sister species occurs more than 500 kilometers away.

“Our objective was to really draw attention due to the unique nature of the discovery and the possibility that the fish is already threatened with extinction”, explains Ramos.

Society’s participation in the discovery

According to him, due to the heavy rains that occurred in 2022 in the state of Rio Grande do Norte, the puddles overflowed and, therefore, the fish were taken to nearby reservoirs. It was in one of these reservoirs that Alberto, the fisherman responsible for the find, discovered the new species. The finding, therefore, is one of many that are only possible thanks to the so-called “citizen science”.

“The region where the fish was found is within a settlement [de trabalhadores rurais] in the municipality of Lagoa Salgada. He saw that it was an unknown fish, took a photo and sent it to a professor at UFRN, who forwarded it to us. Right away, we saw that it was a new species”, recalls the researcher.

In addition to coloring, the H. lulai It has a greater number of dorsal fin rays (basically, what the “lines” that form the fin are called) than other species of the genus, in addition to a high number of stripes on the body.

“This group is one of the most threatened, because of the reproductive cycle: the fish mate, the females lay eggs in temporary lagoons and then these lagoons dry up, and the young will be born when they fill up again. But in that time they can be built there streets, roads, houses, which will end up affecting the animals’ cycle. That’s why, when he saw the fish, he realized it was something different”, explains Ramos.

However, it was not easy to reach the location to collect the individuals. Without resources for research, Ramos and colleagues launched a campaign to raise money for the scientific expedition. They got it through the Instituto Peixes da Caatinga page on Instagram (@peixesdacaatinga).

Despite having managed to visit the site, Ramos now hopes to obtain funding for a research project to continue his studies. This will also help, for example, to carry out a more detailed analysis of the geographic distribution of the new species — whether it is present in other temporary lakes in the region — and its phylogenetic relationships with other species of the genus.

“We still have a lot to study, about ecology, how that group got there, how it separated from the other species [H. longignatus] and how long ago. I want to be able to do this because I have been studying these fish for years, which are very important”, she concludes.