Una nuova popolazione isolata di xenopo liscio in Sicilia sud-occidentale

Abstract

African clawed frog is a sub-saharan native anuran that has been introduced in various states of the old and the new world. The only Italian population of this species is located in western Sicily, and it is known as the European clawed frog population with wider distribution area. This paper describes a new Sicilian population of this species, and sets out to verify the effective isolation from the currently known distribution. The new site is a disused swimming pool, located near the mouth of the Belice River (province of Trapani), 31 km away from the nearest edge of the African clawed frog distribution area. To test whether this new population is the result of natural expansion of its range have been checked 21 control sites, arranged in a suitable area near the new site and along the basin of the Belice River, whose upper course is included in the Sicilian range of this species. The surveys in the control sites did not reveal the presence of clawed frogs, therefore, it seems doubtful the hypothesis of natural expansion along the Belice River basin and plausible the occurrence of a man-mediated introduction event.