title: A new and aberrant species of Dugesia (Platyhelminthes, Tricladida, Dugesiidae) from Madagascar.
abstract: In this paper we report a new species of Dugesia of the family Dugesiidae from Madagascar, representing the fourth species of freshwater planarian known from this global biodiversity hotspot. In some respects the new species is aberrant, when compared with its congeners, being characterized by a head with smoothly rounded auricles, a peculiar course of the oviducts, including the presence of a common posterior extension, and by the asymmetrical openings of the vasa deferentia at about halfway along the seminal vesicle. Further, it is characterized by a ventral course of the ejaculatory duct with a terminal opening, very long spermiducal vesicles and unstalked cocoons. Its diploid chromosome complement with 18 chromosomes represents an uncommon feature among fissiparous species of Dugesia.
authors.affiliation: Dipartimento di Scienze della Natura e del Territorio, Via Muroni 25, University of Sassari, I-07100, Italy.
authors.forename: Giacinta Angela
authors.initials: GA
authors.lastname: Stocchino
authors.affiliation: Naturalis Biodiversity Center, P.O. Box 9517, 2300 RA Leiden, The Netherlands.
authors.forename: Ronald
authors.initials: R
authors.lastname: Sluys
authors.affiliation: Dipartimento di Scienze della Natura e del Territorio, Via Muroni 25, University of Sassari, I-07100, Italy.
authors.forename: Renata
authors.initials: R
authors.lastname: Manconi
keywords: Dugesia; Madagascar; Tricladida; karyology; morphology; new species; reproduction