A new species and new record of Polycystididae (Rhabdocoela: Kalyptorhynchia) from China.

One new species and one newly recorded species of Polycystididae from China, Paulodora sinensis n. sp. and Polycystis ali Schockaert, 1982, were described based on comprehensive morphological and molecular analyses. In Paulodora sinensis n. sp., the stylet is double-walled and is composed of a funnel-shaped proximal part and a spiral distal part, while the outer stylet forms a minor fold proximally. In Polycystis ali Schockaert, 1982, the stylet is also double-walled with a funnel-shaped proximal part. However, the collar-shaped distal part is partially concave and forms a jagged edge. The concatenated 18S rDNA and 28S rDNA phylogenetic analysis supports the establishment of the new species. Besides, based on the morphology of stylet, we have made detailed categorization among the recorded species within these two genera.

Two new species of Kalyptorhynchia (Koinocystididae and Gnathorhynchidae) from China.

Two new species of Kalyptorhynchia (Rhabdocoela), namely Itaipusa sinensis n. sp. (Koinocystididae) and Prognathorhynchus sinensis n. sp. (Gnathorhynchidae) were described from brackish water near Shenzhen Bay, representing the first records of Koinocystididae and Gnathorhynchidae in China. For I. sinensis n. sp., the U-shaped cirrus contains 50 triangular lamellar spines, with two cuticular (pseudocuticular) hooks situated at both sides of its anterior part. The hook I (right side) is funnel-shaped, while the hook II (left side) is triangular lamellar in shape. For P. sinensis n. sp., the proboscis hook has two hooks situated in an anterior to posterior sequence. The semicircular tubular stylet has a hollow spherical dead end posteriorly to the distal opening. Both the morphological and phylogenetic (18S rDNA and 28S rDNA) analyses support the establishment of these two new species.

A new species of the genus Bothrioplana (Platyhelminthes: Bothrioplanida: Bothrioplanidae) and a new species of the genus Pentacoelum (Tricladida: Bdellouridae) from southern China.

Two new species of turbellarians, Bothrioplana sinensis n. sp., and Pentacoelum sinensis n. sp., were described based on their reproductive behavior, ontogenic development, morphology in whole-mounted and sectioned specimens, and 18S rDNA phylogenetic classification. Bothrioplana sinensis n. sp. represents a newly recorded order in China and the second identified species in the genus Bothrioplana. It is characterized by a pair of spherical-shaped well-developed testes located dorsally behind the pharynx, and the common vas deference located ventrally to the gonopore. Phylogenetic analysis showed that this new species is closely related to parasitic flatworms. Pentacoelum sinensis n. sp. is characterized by two uteri instead of lateral bursae located laterally near the tail end and a lack of connection between the posterior intestinal branches. Each uterus has a ventral receptaculum seminalis (also functioning as bursa copulatrix) which has a muscular vagina externa opening obliquely to the ventral side at the tail end.