Sindiplozoon coreius n. sp. (Monogenea: Diplozoidae) from the gills of Coreius guichenoti (Cyprinidae) in China.

Sindiplozoon coreius n. sp. is described from the gills of Coreius guichenoti in Sichuan province, China. There is a smooth tegument and a cup-like widened area in the posterior part of the worm body, which are particular features of the genus Sindiplozoon. There are no branched intestinal caeca before the widened area, but some branches reach the fourth clamp in the hind body; there was no cross striation on the anterior arch of the anterior clamp jaw and medial part of the posterior jaw, which are distinguished from the other species in Sindiplozoon. In addition, S. coreius n. sp. shared the highest ITS2 sequence identity (96.0%) with S. ctenopharyngodoni. The established phylogenetic tree showed that the two species of Sindiplozoon formed a sister group. The k2p genetic distance between the new species and other diplozoids was higher than 3.4%, which suggested interspecific differentiation.