Rhinochimaera costaricana

Rhinochimaera costaricana has a total length ranging from 775 to 830 mm in the known type series, all of which are male. Like other members of its genus, it possesses an elongated, paddle-shaped snout with numerous sensory nerve endings. However, its snout is proportionally shorter than those of its congeners. It is distinguished from all other Rhinochimaera species by a unique combination of traits: a shorter snout, a larger and taller first dorsal-fin spine, a higher first dorsal fin, a wider interdorsal space, and a reduced number of tubercles along the caudal region. The body is dark brown in color, with the fins approaching nearly black. A total of 49 morphometric measurements from the three type specimens were compared against published and unpublished data from more than 90 individuals representing the three previously recognized Rhinochimaera species, confirming the distinctiveness of the Costa Rican specimens.

Rhinochimaera costaricana is known from the Eastern Pacific Ocean, off the Pacific coast of Costa Rica. Specimens have been collected near Isla del Caño and off Cabo Blanco in Puntarenas Province. It has been found at depths ranging from 390 to 787 m (approximately 1,280 to 2,580 ft). All specimens were captured as bycatch during fisheries surveys, suggesting the species may be more widely distributed in the deep waters of the Eastern Pacific than the current limited records indicate.