Symbiosis between the Alpheid Shrimp , Athanas ornithorhynchus Banner and Banner , 1973 ( Crustacea : Decapoda ) , and the Brittle Star , Macrophiothrix longipeda ( Lamarck , 1816 ) ( Echinodermata : Ophiuroidea )

234 * To whom correspondence and reprint requests should be addressed. Ophiuroids are among the most common and conspicuous macro-invertebrates in shallow water habitats. Many species live in association with larger invertebrates, such as sponges, corals and other echinoderms (e.g., Baker et al. 2001, Tominaga et al. 2004, Henkel and Pawlik 2005). However, ophiuroids themselves may serve as hosts for many smaller symbiotic animals, including polychaetes, myzostomids, copepods, amphipods, and shrimps (e.g., Barel and Kramers 1977, Bruce 1982, Volbehr and Rachor 1997, Martin and Britayev 1998). The symbiotic associations between brittle stars and caridean shrimps are rather rare and poorly documented (Bruce 1971 1975 1982). Some of the better-known ophiuroid symbionts among the Decapoda are the pontoniine shrimps of the genus Periclimenes Costa. For instance, Periclimenes lanipes Kemp is associated with the large, gorgonocephalid basket stars (in the ophiuroid order Euryalida), Euryale purpurea Mortensen, Astroboa nuda (Lyman) and Astroglymma sculptum (Döderlein), in the tropical Indo-West Pacific (Bruce 1971 1982, Debelius 2000), while P. perryae Chace is associated with the giant basket star, Astrophyton muricatum (Lamarck), in the tropical and subtropical Western Atlantic (Chace 1972, Humann and Deloach 2002). Symbiosis between the Alpheid Shrimp, Athanas ornithorhynchus Banner and Banner, 1973 (Crustacea: Decapoda), and the Brittle Star, Macrophiothrix longipeda (Lamarck, 1816) (Echinodermata: Ophiuroidea)