Summary (tl;dr)

A new species of deep-sea ghost shark, scientifically named Rhinochimaera costaricana, has been officially discovered and described in the Pacific waters off Costa Rica, generating significant interest in marine biology and unexplored ocean depths.

Essential Background

Ghost sharks, also known as chimaeras, are ancient and mysterious cartilaginous fish that are distant relatives of sharks and rays. These elusive creatures typically inhabit the deep ocean, often characterized by their pale coloring and distinct anatomical features. Until recently, only three species of the Rhinochimaera genus were recognized globally.

The Full Story

An international team of Costa Rican and Brazilian scientists recently announced the official description of a new deep-sea ghost shark species, Rhinochimaera costaricana, in a study published on June 10, 2026, in the scientific journal Zootaxa. This discovery was based on the analysis of three male specimens collected between 2000 and 2023 at depths ranging from 390 to 787 meters in Costa Rica's Pacific waters. Researchers utilized both morphological comparisons and genetic analysis to confirm that Rhinochimaera costaricana is a distinct species, identifiable by unique traits such as a shorter snout, a taller first dorsal fin, and a dark brown body with nearly black fins. The research was led by a biology student from the University of Costa Rica and involved collaborations with Costa Rica's Fisheries and Aquaculture Institute (INCOPESCA) and Brazil's Federal University of Pará.

Why It Matters

This groundbreaking discovery significantly expands our understanding of global marine biodiversity and highlights how much of the deep Pacific ecosystems beyond the continental shelf remain unexplored. The identification of Rhinochimaera costaricana underscores the vital role of advanced technologies, particularly genetic analysis, in distinguishing new species that might have previously been misclassified. This finding also serves as a crucial reminder of the importance of ongoing deep-ocean exploration and conservation efforts, as many deep-sea species may be disappearing before they are ever documented.

Geographic Location

• Pacific Ocean, off the coast of Costa Rica (discovery of Rhinochimaera costaricana)
• Isla del Caño, Puntarenas Province, Costa Rica (location where the first specimen was collected in 2000)
• Cabo Blanco, Puntarenas Province, Costa Rica (location where two specimens were recovered in 2023)
• University of Costa Rica Museum of Zoology, San José, San José Province, Costa Rica (location where specimens were transferred and preserved for scientific study)