Integrative taxonomy unveils two new species of Phagocata (Platyhelminthes, Tricladida, Planariidae) from Northeast China

We describe two new species of the genus Phagocata from Northeast China by applying an integrative approach, including morphological, histological, karyological, and molecular information. The new species Phagocata dentata Chen & Sluys, sp. nov. is characterized by the following features: the dorsal surface of the penis papilla is provided with a number of ridges, of which the distal-most one is about twice as broad and high as the other ridges; vasa deferentia separately and symmetrically opening into mid-dorsal portion of seminal vesicle; a ventrally displaced ejaculatory duct with a ventral, subterminal opening at tip of the papilla; dorsally to the male copulatory apparatus the bursal canal becomes rather wide; male atrium and the common atrium communicate via a significant contraction; chromosome complement diploid, with 2 submetacentric chromosomes and 30 metacentric chromosomes. The new species Phagocata systoleca Chen & Sluys, sp. nov. is characterized by the following features: the bursal canal shows a constriction, due to the presence of a strong sphincter, composed of a cluster of circular muscles that is particularly well-developed on the ventral surface of the canal; testicular follicles located mainly on the ventral side but some follicles extending dorsally to well beyond the midline of the body; the vasa deferentia open separately into the dorsal portion of an elongated, proximal seminal vesicle; from the ventral surface of the latter arises a duct that opens into the antero-dorsal portion of a rather large and sac-shaped distal seminal vesicle, situated in the ventral portion of the penis bulb; the ejaculatory duct follows a ventrally displaced course through the penis papilla and expands to form a balloon-shaped portion with an opening at the rounded tip of the penis papilla; chromosome complement diploid, with 4 submetacentric chromosomes and 30 metacentric chromosomes.