**Ariane Campos 1,\*, M. Antonio Todaro <sup>2</sup> and André Rinaldo Senna Garra**ff**oni <sup>1</sup>**


http://zoobank.org/urn:lsid:zoobank.org:pub:EFA8F92E-7298-4982-B832-54F71E4BB995 Received: 1 December 2019; Accepted: 15 January 2020; Published: 21 January 2020

**Abstract:** The family Turbanellidae includes *Paraturbanella* and five other genera. Despite the fact that the monophyly of these genera were not satisfactorily tested, species belonging to the genus *Paraturbanella* are distinguished from turbanellids by sharing a peculiar group of tubes on the ventrolateral side of the anterior pharyngeal region known as "*dohrni*" tubes. In this study, *Paraturbanella tricaudata* species nova (sp. nov.) from the intertidal zone of a sandy beach in Trindade (Rio de Janeiro State) and the sublittoral sand of Prumirim Island (São Paulo State), Brazil, is described. The new species can be distinguished from all other *Paraturbanella* species by the presence of three caudal cones (one medial and two laterals to it) and peculiar arrangement of the male system. This is the first description of a *Paraturbanella* species from Brazil and the third registered from the Southern Hemisphere (as opposed to 19 species in the Northern Hemisphere); thus, knowledge of marine gastrotrichs biodiversity in this region is far from satisfactory.

**Keywords:** gastrotricha; meiofauna; biodiversity; taxonomy; South America; South Hemisphere; nuclear genes
