日本周辺海域における動吻動物の分類と系統

<p>Recent studies of Japanese kinorhynchs are reviewed. Kinorhynchs (Phylum Kinorhyncha) are ecdysozoan animals with a body composed of head consisted of mouth cone and eversible introvert, neck, and 11 trunk segments. To date, about 230 species have been recorded worldwide, and all of them are exclusively marine meiobenthic species. In Japanese waters, 20 species have been known so far: of these, 9 species were described as new to science or reported as new to Japanese waters within this decade, and 4 species will be described/reported soon. Studies with the molecular phylogenetic and the total evidence analyses detected the phylogenetic relationships within the phylum, and suggested the new classification system. Phylogeographic study of two <i>Echinoderes</i> species detected the geographic population structures of the species, and suggested several historical events had affected to the population structures and distribution patterns of the two species.</p>