A strange marine creature found in the Pacific Ocean has opened a new line of research for scientists at the University of Costa Rica. The specimen, which could be a ghost shark , has unusual physical characteristics and has led scientists to investigate whether it is a new, as-yet-undescribed species.
The discovery was made near Cabo Blanco and Caño Island, two locations on the Costa Rican Pacific coast where specialists found a specimen whose characteristics don't entirely match known species. According to Arturo Angulo Sibaja, a biology professor at the University of Costa Rica, the animal has a shorter snout, a darker coloration pattern, and a much longer dorsal fin spine.
A fish with a prehistoric past
So-called ghost sharks are not sharks in the strict sense, although they are related to them. They belong to the group de peces cartilaginous known as Rhinochimaera, an evolutionary line that genetically diverged from sharks almost 400 million years agoThis antiquity explains some of the interest these animals generate among marine biologists. Until now, three species of ghost shark had been documented in other regions of the world, including waters off South Africa, Taiwan, Australia, Japan, and the Atlantic between Greenland and Brazil. The possible Costa Rican species would be especially relevant because, according to Sibaja, It would be the only one known on the coast of Central America.
The research is not based solely on the animal's external appearance. Genetic analyses conducted so far indicate that this ghost shark has no reproductive contact with other known groups, an important piece of information for assessing whether it is a distinct species. Even so, science typically requires a thorough review of available specimens before finalizing a taxonomic description. Biology student Naidely Vidaurre Quesada, from the University of Costa Rica, is participating in the examination of the specimen, while the team continues comparing its characteristics with available records. For Arturo Angulo Sibaja, it is "most likely" that this possible new species has a wider distribution along the Pacific coast of Central and South America, a hypothesis that could change what is known about these elusive inhabitants of the deep.
Features that make it unique
The new species, named Rhinochimaera costaricana in honor of Costa Rica, measures about 80 centimeters and lives at depths of 400 to 700 meters, in an environment of total darkness and extreme pressure. Its body is dark brown, with nearly black fins and an elongated, paddle-shaped snout. Scientists based the description on three male specimens collected between 2000 and 2023 : the first was found near Isla del Caño, and the other two off Cabo Blanco, in Puntarenas, during deep-sea research expeditions. According to the researchers, this species is distinguished by its shorter snout, darker coloration, and much longer dorsal spine compared to other known chimeras.
The discovery adds to a series of recent investigations seeking to better understand deep-sea ecosystems, considered among the least explored environments on the planet. These are habitats where sunlight does not penetrate and extreme pressure and temperature conditions force species to develop unique adaptations. Scientists emphasized that this type of finding not only expands the catalog of the world's rarest fish but also allows for a better understanding of the evolution of animals that inhabit these extreme environments.
The scientific community emphasizes that each new record contributes to reconstructing the functioning of marine ecosystems as a whole, particularly in areas where human activity is still limited. Despite technological advances in underwater exploration, it is estimated that much of the deep ocean remains unstudied in detail. In this context, each scientific expedition can lead to discoveries relevant to marine biology. The discovery of the ghost shark in Costa Rica reinforces the idea that the oceans remain one of the most unknown territories on the planet, with species that have yet to be described by science. Based on this data, teams will seek to determine its geographic distribution, feeding habits, and possible evolutionary links with other chondrichthyans previously identified in different regions of the eastern Pacific Ocean.