THREE NEW SPECIES OF THE DEEP-SEA GENUS COLLETTEA LANG, 1973 (TANAIDACEA; COLLETTEIDAE) IN THE EASTERN CENTRAL PACIFIC

Abstract

Three new species of Collettea Lang, 1973 are described from the Korea Deep Ocean Study (KODOS) area of the eastern central Pacific based on collections made at a depth of approximately 5000 m by RN Onnuri. This study is a component of environmental impact research for manganese nodule mining in the Clarion-Clipperton Fracture Zone (CCFZ). Only one species of the genus Collettea has previously been described from the CCFZ. This situation may result from similar morphologies among related species, a lack of samples, and the frequent poor quality of specimens which results from sampling difficulties. This paper describes three new Collettea species from the KODOS area. These species vary in the characteristics of the cheliped propodus: in C. aspera and C. prominentia, this structure shows bark-like ornamentation on its outer surface. Additionally, the cephalothorax bears fine setules along the mid-lateral margins (C. eminula and C. aspera), and the cheliped fixed finger shows protrusions along the proximal incisive margin (C. eminula). These characteristics have not yet been found in other species of the genus. In this study, full descriptions of new species of Collettea and the key characters of genus are provided, and the comparison of these characteristics with those of closely related species is given.