title: A new leech species (Clitellata: Hirudinida: Piscicolidae) from the Łyna River near Olsztyn, Poland.
abstract: A new species of fish leech from Poland, Piscicola burresoni n. sp. (Piscicolidae), is described. The leech was found in 2007 on stones and on pike ( Esox lucius L.) and chub ( Leuciscus cephalus L.) in the Łyna River, Poland. The leech is small, relatively flattened, with a prominent coarctation between the trachelosome and urosome. The pigmentation is unique to the new species and it has 14 annuli with gonopores separated by 4 annuli. The receptaculum seminis consists of an elliptical aperture located at a distance of 3 annuli behind the female gonopore. The copulatory area on the clitellum is characteristic in the shape of a parallel ellipse. The vector tissue is in the form of a transverse plate below the oviduct outlet. For a complete description of the external morphology, a geometric-mathematical model of the leech body form was used.
authors.affiliation: Department of Zoology, University of Warmia and Mazury, Oczapowskiego 5 St, 10-719 Olsztyn, Poland.
authors.forename: Aleksander
authors.initials: A
authors.lastname: Bielecki
authors.forename: Joanna M
authors.initials: JM
authors.lastname: Cichocka
authors.forename: Piotr
authors.initials: P
authors.lastname: Świątek
authors.forename: Małgorzata
authors.initials: M
authors.lastname: Gorzel
mesh_terms: D058500:Animal Fins / Q000469:parasitology; D000818:Animals; D003530:Cyprinidae / Q000469:parasitology*; D004478:Ectoparasitic Infestations / Q000469:parasitology / Q000662:veterinary*; D017859:Esocidae / Q000469:parasitology*; D005393:Fish Diseases / Q000469:parasitology*; D007865:Leeches / Q000033:anatomy & histology / Q000145:classification*; D011044:Poland; D045483:Rivers