Once the lesion had sealed (by day 3), regeneration of mantle tissue was rapid and complete. Byssus production by P. fucata one week after mantle excision has previously been reported (Acosta-Salmo ´n et al., 2004) and indicates that the damage caused when excising mantle tissue and the energetic cost of the healing and regeneration process do not interfere with other body functions. Mantle tissue surrounding the wound site in P. fucata grew in two directions: (1) ventrally towards the shell margin from the mantle central zone forming the pallial and marginal zones and (2) laterally with the ends of the wound healing and growing towards each other reducing the length of the lesion.