Sur la présence en France de Trocheta taunensis Grosser, 2015 (Hirudinida, Erpobdellidae)

Since the 1950s, a leech species of the genus Trocheta has been cited from France and named Trocheta bykowskii Gedroyć, 1913. Work by Košel in 2004 and then by Grosser in 2015 on the populations of eastern Europe made it possible to better understand the taxonomy of this taxon which turn out to be a junior synonym of Trocheta cylindrica Örley, 1886. This species, whose distribution is restricted to the Carpathians, is in fact not present in Western Europe. The unicoloured species named bykowskii from these western countries has been described under the name Trocheta taunensis Grosser, 2015. Investigation of leeches named Trocheta bykowskii from France showed that these related to the newly described species T. taunensis and not to T. cylindrica. The main difference lies in examining the reproductive system and in particular the atrium, which is very elongated in taunensis. The data of T. bykowskii from France are now to be linked to the species T. taunensis. Currently, four species of the genus Trocheta have been recorded in France, T. subviridis and T. pseudodina are certainly present throughout France. T. falkneri is a leech endemic to the Pyrenees. The geographical distribution of T. taunensis was established thanks to our field observations as well as the analysis of the bibliography available on the subject. The species has been recorded in eastern France, from the departments of Drôme in the south, to the Doubs in the north and the Rhône in the west. An identification key for species of the genus Trocheta present in France is presented.