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 Author Angulo, Arturo Author López, Myrna I. Author Bussing, William A. Author Murase, Atsunobu text Zootaxa 2014 2014-09-18 3861 6 554 574 journal article 4098 10.11646/zootaxa.3861.6.3 38808f1d-0656-4659-bc31-0e5eee066ed6 1175-5326 5247997 8169FF7C-74C0-4385-8B67-09306D815CD2 Key to eastern Pacific species of the order Chimaeriformes The following key is based on our research and data available in the literature (Didier & Nakaya 1999, Didier & Rosenberger 2002, Barnett et al. 2006 , Nelson 2006 , Quaranta et al. 2006 , Didier & Meckley 2009a , b, James et al. 2009 , González-Acosta et al. 2010 , Bustamante et al. 2012 , Didier et al. 2012 ). 1 Snout with elongate, flexible, hooklike process; lateral line canals closed; second dorsal fin not elongate; tail heterocercal ( Ecuador to Argentina )............................................. Callorhinchus callorynchus (Linnaeus 1758) - Snout short and rounded or long and pointed, not hooklike; lateral line canals are open grooves; second dorsal fin elongate; tail diphycercal.......................................................................................... 2 2 Snout short and bluntly rounded; caudal-fin axis horizontal with the fin nearly symmetrical, epaxial and hypaxial lobes equal sized............................................................................................... 3 - Snout elongated and pointed; caudal-fin axis weakly raised with the fin asymmetrical, epaxial caudal-fin lobe narrower than hypaxial lobe........................................................................................ 8 3 Anal fin present ( Costa Rica to Peru , probably more widespread in the southeastern Pacific).... Chimaera orientalis sp. nov . - Anal fin absent...................................................................................... 4 4 Anterior and posterior regions of second dorsal-fin considerably taller than middle region............................ 5 - Second dorsal-fin uniform in height throughout............................................................. 7 5 Anterior edge of dorsal-fin spine not serrated; uniform dark brown to reddish-brown across entire body with numerous white spots on the head and trunk (Gulf of Alaska to Costa Rica )................... Hydrolagus colliei (Lay & Bennett 1839) - Anterior edge of dorsal-fin spine serrated; uniform brown across entire body with or without a distinct white spot on the lateral side above the pectoral fins............................................................................. 6 6 Snout blunt; EYL more than 40% HDL; tail region short and stout, PCA less than 57% BDL; uniform brown across entire body with a distinct white spot on the lateral side above the pectoral fins ( Galapagos Islands )................................................................................. Hydrolagus alphus Quaranta, Didier, Long & Ebert 2006 - Snout pointed at tip; EYL less than 40% HDL; tail region elongate and slender, PCA more than 58% BDL; uniform brown across entire body with no white markings ( Mexico to Chile )................ Hydrolagus macrophthalmus de Buen 1959 7 EYL more than 10% BDL; two narrowly spaced columns of serrations on the posterolateral edges of the distal 66–75% of spine (in adults); uniform overall medium grey on dorsal and lateral parts extending to near the ventrum, and dorsum with many irregular circular and elongate white blotches ( Galapagos Islands )................................................................................................. Hydrolagus mccoskeri Barnett, Didier, Long & Ebert 2006 - EYL less than 9% BDL ; spine serrations very worn, posterior edge of spine serrated for last 6.5–13% of spine length (in adults); uniform dark brown to black across entire body with a lighter band over the snout ( Southern California , U.S.A. to Chile )............................................. Hydrolagus melanophasma James, Ebert, Long & Didier 2009 8 Tooth-plates with ridges and knobs; eyes virtually above mouth; upper edge of caudal fin without denticles or tubercles (Southern California , U.S.A. , to Peru )......................................... Harriotta raleighana Goode & Bean 1895 - Tooth-plates nearly smooth; eyes distinctly behind level of mouth; caudal tubercles present along the upper edge of caudal fin .................................................................................................... 9 9 Snout broad and paddle-shaped with fleshy tip; junction of supraorbital and infraorbital canals on ventral side of snout closer to the tip of the snout than to the nasal canal; ONC/TIO greater than 1.4, TIO/SWF less than 1.5, TIO/LNC less than 3.0; 25–47 dorsal caudal tubercles in mature specimens; even dark brown color over entire body ( Costa Rica to Peru )............................................................. Rhinochimaera africana Compagno, Stehmann & Ebert 1990 - Snout narrow and conical shaped with the tip narrow and stiff; junction of supraorbital and infraorbital canals on ventral side of snout nearly equidistant between the tip of the snout and the nasal canal; ONC/TIO less than 1.4, TIO/SWF greater than 1.5, TIO/LNC greater than 3.0; 36–62 dorsal caudal tubercles in mature specimens; pale brownish-gray body color with fins darker ( Peru ).............................................................. Rhinochimaera pacifica (Mitsukuri 1895)