Salinity effects on arm regeneration in Luidia clathrata (Echinodermata: Asteroidea)

Abstract

The effect of salinity (20, 25, and 30 psu) on regeneration of two arms of adult starfish Luidia clathrata (n = 8 per salinity treatment group collected from Pensacola Bay, Florida, USA 30° 20′ N, 87° 13′ W) was examined in a laboratory experiment (November 2009 to March 2010) to test the hypothesis that L. clathrata is adapted to euryhaline conditions found in bays with regards to arm regeneration. Regenerating arm condition (lengths and weights) relative to treatment was 20-psu treatment < 25-psu treatment < 30-psu treatment, and non-regenerating arm condition was 20-psu treatment < 25-psu treatment = 30-psu treatment. Luidia clathrata is not adapted to lower salinity conditions found in bays with regard to arm regeneration, despite the common occurrence of the species in bays. Lower salinity in bays should reduce the ability of L. clathrata to recover from damage sustained during, or just prior to, low-salinity periods.

Keywords:

• Echinodermata
• Asteroidea
• Luidia clathrata
• starfish
• salinity
• autotomy
• regeneration

Acknowledgements

We thank the undergraduate honor's program at the University of West Florida for providing partial funding for this project. We thank Addison Lawrence and John Lawrence for providing the artificial feed. We thank the crew of the Florida Institute of Oceanography vessel “R/V Bellows” for providing support during collection of the starfish.