Two unrecorded marine nematode species of genus Paracanthonchus (Nematoda: Cyatholaimidae) from the East Sea of Korea

Abstract

Two unrecorded marine nematode species, belonging to genus Paracanthonchus Micoletzky, 1924 are described on the basis of the specimens collected from rocky intertidal seagrass bed on the eastern coast of Korea. Paracanthonchus macrodon Micoletzky, 1924 is characterized by presence of cuticular differentiation, strongly dilated gubernaculum with numerous cusps, presence of three post-cloacal setae, and arrangement of six (4+2) precloacal supplement. Paracanthonchus kamui Kito, 1981 is distinguished from the other species of the genus by having the 4.25 turns amphideal fovea, gubernaculum rib-like structure with proximally hook-shaped, distally broaden and four tubular, and two delicated supplement. In this study, we provide detailed morphological features, taxonomic description and illustration of unrecorded species of the genus Paracanthonchus by differential interference contrast microscopy. This is the first report on the species of the genus Paracanthonchus from the Korea.oletzky, 1924 is characterized by presence of cuticular differentiation, strongly dilated gubernaculum with numerous cusps, presence of three post-cloacal setae, and arrangement of six (4+2) precloacal supplement. Paracanthonchus kamui Kito, 1981 is distinguished from the other species of the genus by having the 4.25 turns amphideal fovea, gubernaculum rib-like structure with proximally hook-shaped, distally broaden and four tubular, and two delicated supplement. In this study, we provide detailed morphological features, taxonomic description and illustration of unrecorded species of the genus Paracanthonchus by differential interference contrast microscopy. This is the first report on the species of the genus Paracanthonchus from the Korea.