The southward spread in Mediterranean Sea of the potentially invasive Polycera hedgpethi is documented by first reports from North African Mediterranean coasts. Overall, ten specimens were recorded, along 20 km of coastline in the Gulf of Tunis, from spring to autumn 2018, while no specimen was found in the following winter, according to the known life-cycle of the species. The related thermohaline range is here reported, together with on field observations. Specimen morphology and chromatic pattern have been described in detail. The records, close to the biggest commercial harbor in north Tunisia, suggested a probable shipmediated introduction, favored by the known adaptability of this species to polluted environments. The sequence of P. hedgpethi records in Mediterranean, from colder towards warmer biota, is explained assuming that commercial fluxes were in charge of early transient occurrence in northern areas before settling in more climatically favorable eco-region.
To go counter-current? The introduced sea slug Polycera hedgpethi Er. Marcus, 1964 (Nudibranchia: Polyceridae) spreads southwards in Mediterranean Sea
Salvatore GIACOBBEMembro del Collaboration Group
2019-01-01
Abstract
The southward spread in Mediterranean Sea of the potentially invasive Polycera hedgpethi is documented by first reports from North African Mediterranean coasts. Overall, ten specimens were recorded, along 20 km of coastline in the Gulf of Tunis, from spring to autumn 2018, while no specimen was found in the following winter, according to the known life-cycle of the species. The related thermohaline range is here reported, together with on field observations. Specimen morphology and chromatic pattern have been described in detail. The records, close to the biggest commercial harbor in north Tunisia, suggested a probable shipmediated introduction, favored by the known adaptability of this species to polluted environments. The sequence of P. hedgpethi records in Mediterranean, from colder towards warmer biota, is explained assuming that commercial fluxes were in charge of early transient occurrence in northern areas before settling in more climatically favorable eco-region.Pubblicazioni consigliate
I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.