Naidely Valeria Vidaurre Quesada led the formal description of a new deep-sea ghost shark Costa Rica species, Rhinochimaera costaricana, published on June 10 in Zootaxa. The Biology student at the University of Costa Rica worked with the Costa Rican Institute of Fisheries and Aquaculture and the Federal University of Pará on the paper.
The species was described from three male specimens collected between 2000 and 2023 at depths of 390 to 787 meters in the Costa Rican Pacific. Those specimens measured between 775 and 830 millimeters in total length.
UCR and Incopesca
The team used specimens from scientific collections to build the description, and biologists from Incopesca originally recovered and protected two of the three during fisheries research expeditions. The specimens were later transferred to the scientific collections at the UCR Museum of Zoology, giving the paper physical material that could be compared across years rather than a single recent catch.
Rhinochimaera is a genus of chimaeras, a group commonly known as ghost sharks. Before this paper, the genus included three recognized species worldwide: R. africana, R. atlantica, and R. pacifica.
Natural History Museum in London
Vidaurre Quesada traveled to the Natural History Museum in London to review historical global archives after the publication. That step fits the way the species was separated from its relatives: the team relied on a unique combination of morphological traits and genetic evidence, not just one specimen from one trip.
The genetic sequences showed differences of 3.9% compared with R. africana, 4.5% compared with R. atlantica, and 4.7% compared with R. pacifica. Those gaps, alongside the physical traits, were the basis for recognizing Rhinochimaera costaricana as distinct.
Costa Rican Pacific specimens
The timeline explains the delay in the name. The first specimen was found in 2000 near Isla del Caño, while the other two came from 2023 off Cabo Blanco, Puntarenas. The species was only formally described in 2024, after the older material, the newer captures, and the archived collections could be compared in one scientific paper.
For Costa Rica, the result is a named species from deep water in its Pacific zone, built from specimens already preserved for study. The next step is scientific use of the material already assembled: continued comparison, archiving, and citation by researchers working on the Rhinochimaera genus.
