Habitat Distribution and Comparison of Brittle Star (Echinodermata: Ophiuroidea) Arm Regeneration on Moorea, French Polynesia

Autotomy and regeneration are widespread in many groups of invertebrates and vertebrates, such as annelids, crustaceans, amphibians, and reptiles. Regeneration is common in all classes of Echinodermata and prevalent in ophiuroid brittle stars. Moorea, French Polynesia was surveyed for species of brittle stars living on coastal areas of the island in different habitats. Ophiuroid populations were sampled in habitats such as a mangrove marsh, a sandy beach with coral rubble and a jetty with coral rubble and conglomerate coral to determine percentages with regenerating arms. Macrophiothix longipeda (Lamarck 1816) from the mangrove marsh and two populations of Ophiocoma scolopendrina (Lamarck 1816) from the beach and jetty were studied to determine if there were differences in experimental rates of arm regeneration after induced autotomization. Each habitat was colonized by distict ophiuriod assemblages and had different percentages of regenerating individuals; M. longipeda was found to be regenerating multiple arms simultaneously and had the highest rate of regeneration. Regeneration rates differed by species; mostly likely influenced by habitat, ecology and biology of each species.