Oxytrichidae 과에 속하는 신속 후보 (원생동물: 섬모충문)

Abstract

Two new oxtrytrichids were discovered from brackish water from South Korea. Based on morphology, ontogenesis, and molecular analyses, we confirm that these species belong to new genus. The new candidate genus has similar morphology to Cyrtohymena (i.e., typical 18-cirri, Cyrtohymena undulating membranes pattern), however, the candidate genus can be distinguished mainly by decreased/lacking of caudal cirri and lacking of dorsal kinety fragmentation. On gene tress of 18S rDNA sequences, the new two species were clustered together and showed a sister relationship with Cyrtohymena-Notohymena-Paraurostyla. In addition, our results support that the oral apparatus of Cyrtohymena might be evolved two times or existed in last common ancestor, and more taxon-samplings of DNA sequences are necessary to reconstruct a robust phylogenetic tree for better understanding of their relationships.hymena (i.e., typical 18-cirri, Cyrtohymena undulating membranes pattern), however, the candidate genus can be distinguished mainly by decreased/lacking of caudal cirri and lacking of dorsal kinety fragmentation. On gene tress of 18S rDNA sequences, the new two species were clustered together and showed a sister relationship with Cyrtohymena-Notohymena-Paraurostyla. In addition, our results support that the oral apparatus of Cyrtohymena might be evolved two times or existed in last common ancestor, and more taxon-samplings of DNA sequences are necessary to reconstruct a robust phylogenetic tree for better understanding of their relationships.