First record of the opal chimaera, Chimaera opalescens (Holocephali: Chimaeridae) and revision of the occurrence of the rabbitfish Chimaera monstrosa in the Azores waters

The presence of the opal chimaera, Chimaera opalescens, is reported for the first time in the deep waters of the Azores, with the capture of four specimens by fishermen and the video recording of an additional five individuals. Species identification was supported by the 646 bp sequenced fragment of the mitochondrial gene cytochrome oxidase subunit I. Because C. opalescens is a recently recognised species that had been recurrently misidentified as rabbitfish, Chimaera monstrosa, the historical data of C. monstrosa in the Azores were reviewed to assess the possible presence of both Chimaera species in the region. Although several authors have reported the occurrence of C. monstrosa in the Az…