First record of the potentially invasive Pinctada imbricata fucata (Gould, 1850) (Bivalvia Pteriidae) along the Mediterranean coasts of Spain.
The taxonomy of pearl oyster species Pinctada Röding, 1798 (Bivalvia Pteriidae) is difficult due to the intraspecific variability of their morphological characters, making them hard to distinguish. However, previous studies reported the existence of two different taxa of this genus in the Mediterranean Sea; Pinctada imbricata radiata (Leach, 1818) and Pinctada imbricata fucata (Gould, 1850). Pinctada imbricata radiata is one of the first lessepsian species to be reported and it is nowadays considered a well-stablished species in the Mediterranean basin. P. imbricata fucata is native to the Indo-Pacific Ocean and entered the basin only in recent time. The first time this species was found in the Mediterranean was in 2015 for Sicily (Italy). In the present work, the Pteriidae species Pinctada imbricata fucata is reported for the first time in the Mediterranean waters of south Spain. This finding enlarges the known distribution of this alien species to the western side of the basin.