First record of the cirripede Anelasma squalicola Darwin, 1852 (Pollicipedidae) in the Mediterranean Sea.

Anelasma squalicola Darwin 1852, is a barnacle that occurs on elasmobranchs from the Atlantic, Pacific, Arctic and Indian Ocean. It infects sharks of the families Etmopteridae and Pentanchidae. The barnacle attaches sub-dermally to its hosts, relying on its interstitial fluid for its nourishment. Herein we present the first record of this species in the Mediterranean Sea, from Etmopterus spinax (Linnaeus, 1758) caught during a bottom-trawl survey in the Alboran Sea (western Mediterranean) in 2017. The overall prevalence of infection was very low (0.22%). The calculated HSI index for the parasitized individual was lower compared to overall means of other individuals and could indicate a potential physiological alteration in the host.