Detection of lamprey in Southernmost South America by environmental DNA (eDNA) and molecular evidence for a new species

NARDI, CRISTINA FERNANDA; SÁNCHEZ, JULIETA; FERNÁNDEZ, DANIEL ALFREDO; CASALINUOVO, MIGUEL ÁNGEL; ROJO, JAVIER HERNÁN; CHALDE, TOMÁS

POLAR BIOLOGY

SPRINGER

Año: 2020 vol. 43 p. 369 - 383

0722-4060

Lampreys are jawless fishes belonging to the order Petromyzontiformes. Geotria australis is the sole representative lampreyspecies of the Geotriidae family and is widely distributed around South America, Australia, New Zealand, and sub-AntarcticIslands. In South America, the presence and distribution of G. australis are well characterized in Western Patagonia, in riversflowing into the Pacific Ocean. In contrast, there is scarce information about the presence of this species in Eastern Patagonia,in rivers flowing into the Atlantic Ocean. Here, we provide the first report on the distribution of lamprey at the extremesouth of Patagonia and suggest the occurrence of a new lamprey species. We developed an environmental DNA (eDNA)method to detect G. australis from water samples and obtained positive results in five basins flowing into the Atlantic Oceanand one river basin flowing into the Beagle Channel. Lampreys were captured from two eDNA-positive basins and used forgenetic analysis. An 875 bp-sequence of the cytochrome b mitochondrial gene was obtained, and a phylogenetic analysiswas carried out with this sequence and those available in GenBank, revealing Argentinean lamprey reported here, as a sisterspecies of G. australis from Chile, Australia, and New Zealand. Also, the genetic distance values between lamprey reportedhere and G. australis were consistent with the genetic distances between species of different genera. Our results suggest thatthe Argentinean lamprey corresponds to a new specific taxon that could represent a new monotypic genus in Geotriidae.