Bigeye Chimaera

diagnosis

Diagnosis. Body slender; snout short and bluntly rounded; head relatively short (HDL 24.2 – 24.5 % BDL); eyes relatively large (EYL 30.9 – 34.2 % HDL); oral and preopercular lateral line canals sharing a short common branch from the infraorbital canal; pectoral fins relatively large (P 1 A 36.5 – 40.8 % BDL), extending posterior to the insertion of pelvic fins; lateral line canal of the trunk without sinusoidal undulations; anterior and posterior regions of second dorsal fin considerably taller than middle region; anal fin absent; tail region elongate and slender (PCA 58.3 – 59.9 % BDL); caudal-fin axis horizontal with the fin nearly symmetrical, epaxial and hypaxial lobes equal sized; uniform brown coloration across entire body, with no white markings; bluish fins. Additional morphometric measurements, expressed as percentage of body length (% BDL) or head length (% HDL), and comparative data are presented in Table 5.

Records of chimaeroid fishes (Holocephali: Chimaeriformes) from the Pacific coast of Costa Rica, with the description of a new species of Chimera (Chimaeridae) from the eastern Pacific Ocean

discussion

Remarks. Although this species has a postulated distribution extending from the central coast of Mexico (González-Acosta et al. 2010) to Chile (Didier & Meckley 2009 b), there are no published records between Mexico and Peru (Didier & Meckley 2009 b). The discovery of these specimens in Costa Rican waters increases the knowledge of its marine ichthyofauna and provides evidence of a broader distributional pattern for this species in the eastern Pacific region.

Records of chimaeroid fishes (Holocephali: Chimaeriformes) from the Pacific coast of Costa Rica, with the description of a new species of Chimera (Chimaeridae) from the eastern Pacific Ocean

distribution

Distribution. Eastern Pacific: Central coast of Mexico (González-Acosta et al. 2010), Costa Rica (this study), Peru and Chile, at depths of 590 – 1160 m (Didier & Meckley 2009 b).

Records of chimaeroid fishes (Holocephali: Chimaeriformes) from the Pacific coast of Costa Rica, with the description of a new species of Chimera (Chimaeridae) from the eastern Pacific Ocean

materials_examined

Material examined. 4 specimens. UCR 2611 – 08, n = 2, females, 435 – 581 mm TL, 223 – 343 mm BDL; in front of Playa Coyote, Península de Nicoya, Guanacaste, Costa Rica (9 ° 40 ' 50.02 " N, 85 ° 28 ' 4.81 " W), 650 – 700 m, 7 April 2000, collected by M. Vitola. UCR 2901 – 01, n = 2, females, 543 – 639 mm TL, 334 – 349 mm BDL; 44.95 Km, 253.73 ° T from Cabo Blanco, Puntarenas, Costa Rica (9 º 26 ' 16.44 " N, 85 º 29 ' 56.04 " W), 560 – 620 m, 24 November 2010, collected by J. M. Carvajal.

Records of chimaeroid fishes (Holocephali: Chimaeriformes) from the Pacific coast of Costa Rica, with the description of a new species of Chimera (Chimaeridae) from the eastern Pacific Ocean