Tentacular autotomy and polyp regeneration in the scleractinian coral Euphyllia glabrescens
Scleractinians reproduce asexually via a variety of mechanisms, including fragmentation, budding, planulae production, polyp expulsion and bailout (Piraino et al. 2004). More recently, autotomy has been documented as another means of asexual reproduction (Hoeksema and Waheed 2012); this mechanism involves skeletal dissolution and is limited to solitary fungiids. Here, we report an observation of tentacular autotomy and polyp regeneration in the coral Euphyllia glabrescens (Chamisso and Eysenhardt, 1821).
Tentacular autotomy and polyp regeneration have been reported in actinians and alcyonareans and can occur as a response to predation (Piraino et al. 2004), but is as yet undocumented in scleractinians. As autotomy occurred after the parent E. glabrescens colony was mechanically agitated, we inferred that the behavior was a stress-induced response. This strategy may be used by some colonial scleractinians as a means of asexual reproduction and could potentially be developed as a propagation technique for reef restoration. Future investigations should focus on examining the likelihood of this phenomenon in natural populations.
We would like to thank N.W.L. Yap for his helpful discussion and acknowledge the contributions of S. Gunasekaran and L.M. Chou.