Effects of salinity and feeding on arm regeneration in the starfish Luidia clathrata (Say, 1825) (Echinodermata: Asteroidea)

ABSTRACT The aim of this study was to determine: (1) salinity that maximizes arm regeneration in the starfish Luidia clathrata; and (2) if low food consumption or low salinity is the cause of the reduced rate of arm regeneration seen at low salinities.. An estimated salinity of 33 g kg−1 produced maximum regeneration of two arms in L. clathrata. This salinity is typically greater than that found in bays that are the usual habitat for the species. Equivalent food consumption by L. clathrata in salinities of 20 g kg−1 and 30 g kg−1 resulted in greater regeneration in salinity of 30 g kg−1, suggesting lower food consumption at low salinities is not the primary reason for lower regeneration. Higher food consumption compared to lower food consumption, both tested in salinity of 30 g kg−1, did not increase regeneration, but resulted in more storage of energy in the pyloric caeca.