Keywords
alien species
Ionian Sea
Mediterranean
Lessepsian migrant
How to Cite
Abstract
The Lessepsian jellyfish Cassiopea andromeda is an invasive scyphozoan originating from the Red Sea and In-do-Pacific region. It was first recorded in the Mediterranean at the beginning of the 20th century and has since expanded its distribution across the basin. The main goal of this contribution is to document the first and well-doc-umented record of this jellyfish from the Portopalo di Capo Passero area, which represents the southernmost tip of Italy (Sicily, Ionian Sea). The observation, made in October 2025, provides new evidence of the species’ expansion along the Sicilian Ionian coast. This finding raises questions about whether the species is a recent colonizer or an overlooked resident and highlights the biogeographical and ecological importance of this area as a potential hotspot for the monitoring of Lessepsian and thermophilic species.
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