First report of Alvania scuderii Villari, 2017 (Gastropoda: Mollusca) from Tyrrhenian Sea: Some biogeographic implications

Abstract
The cryptic gastropod Alva-nia scuderii Villari, 2017, recently described from the Strait of Messina as new species inside the A. scabra (Philippi, 1844) group, was known by restricted areas of eastern and southern Sicily. Some records from the type locality and south-eastern Tyrrhenian sea, which pro-vided new data on habitat and bathymetric range, also enlarged northward, in a further basin, the known ar-eal. Such areal, that over-laps a Mediterranean west-ern-eastern biogeographic boundary, may be consid-ered a further clue of an hy-drological front that is re-sponsible of a West-Mediterranean footprint more marked than in nearby North-westernmost areas.