"This is one of a group of four similar-looking European species of Aeoliodiella (Aeolidiella papillosa, Aeolidiella sanguinea and Aeolidiella alderi). Aeolidiella glauca is characterised externally by the pale cream pigment in patches on the outside of the cerata, particularly the lateral cerata."
Comment from Richard Willan
This is one of a group of four similar-looking European species of Aeoliodiella (Aeolidiella papillosa, Aeolidiella sanguinea and Aeolidiella alderi). Aeolidiella glauca is characterised externally by the pale cream pigment in patches on the outside of the cerata, particularly the lateral cerata.