Abstract：
We establish a new interstitial polyclad species, Theama japonica sp. nov., based on specimens collected from coarse-sandy habitats in three Japanese main islands (Hokkaido, Honshu, and Shikoku) along the coasts of the Pacific Ocean and the Sea of Japan. Theama japonica is characterized by i) two pairs of cerebral eyespots and four to six precerebral eyespots; ii) eosinophilic secretion glands distributed in the distal half of the inner ventral part of the prostatic vesicle; iii) a conical penis papilla, bent up dorsally, with a sclerotized inner wall; iv) the prostatic sheath with an inner angular fold on the dorso-distal side; and v) the external cilia longer dorsally than ventrally. Partial sequences of the cytochrome c oxidase subunit I (COI) gene from 20 specimens collected at eight localities along Japanese coasts represented 19 haplotypes. The uncorrected p-distances among these COI haplotypes fell within intraspecific variations observed in other polyclads. A network analysis based on these COI haplotypes suggested a geographically non-cohesive genetic structure of the species, possibly indicating the species\' high dispersibility. Molecular phylogenetic analyses based on a concatenated dataset of 18S and 28S rDNA sequences showed T. japonica formed a clade with other Theama species. The resulting tree also indicates that our new species is more closely related to Theama sp. from Colombia than species from Panama and Croatia.
摘要：
我们建立了一种新的间质多包层物种，日本茶。11月。,根据从日本三个主要岛屿(北海道，本州,和四国）沿太平洋和日本海的海岸。Theamajaponica的特征在于i）两对脑眼点和四至六个脑前眼点；ii）嗜酸性粒细胞分泌腺分布在前列腺囊内腹部远半部；iii）圆锥形阴茎乳头，背部弯曲，具有硬化的内壁；iv）前列腺鞘在背远侧有内角折叠；v）背侧的外部纤毛长于腹侧。来自日本沿海八个地区收集的20个标本的细胞色素c氧化酶亚基I（COI）基因的部分序列代表19个单倍型。这些COI单倍型之间未校正的p距离落在其他多束层中观察到的种内变异内。基于这些COI单倍型的网络分析表明，该物种在地理上具有非粘性遗传结构，可能表明该物种的分散性很高。基于18S和28SrDNA序列的串联数据集的分子系统发育分析表明，T.japonica与其他Theama物种形成了进化枝。由此产生的树也表明我们的新物种与Theamasp更密切相关。来自哥伦比亚的物种比来自巴拿马和克罗地亚的物种。
