Sipunculans and Echiurans of Isla del Coco (Cocos Island), Costa Rica Author Vargas, Rita Author Kawauchi, Gisele Y. text Zootaxa 2010 2557 60 68 journal article 10.5281/zenodo.196936 a2d81a5c-6c54-40d9-946d-86fa5224d0fd 1175-5326 196936 Aspidosiphon elegans Chimisso & Eysenhardt, 1821 Bahía Chatham, 11m , 26 May 2008 , one specimen, 6.5 mm; Isla Manuelita, 4.5 m, 29 May 2008 , one specimen, 1.5 mm; Punta Ulloa, SCUBA, calcareous rocks, 12 October 2007 , one specimen, 14 mm ; 12 m , reef, 23 May 2008 , three specimens, 3.5 to 4.5 mm; 3 m , 28 May 2008 , four specimens, 4–40 mm ; 8 m , 28 May 2008 , one specimen, 16 mm . Additional material . Bahía Chatham, subtidal sand bottom, 30m , 12 October 2007 , 1 specimen , 10 mm ; Bahía Wafer 20m , 10 April 2008 , 2 specimens , 11–12mm ; Silverado 11m 23 May 2008 , 9 specimens , 10- 30mm . Description : This species is easily recognized by the dark pyramidal hooks proximal to the rings of bidentate hooks and the well demarcated, ungrooved shield made up of large irregular units. Nephridia were 65–75% the body length. Habitat. Subtidal calcareous rock, sand bottom, 3- 30 m . Distribution. Aspidosiphon elegans is a widely distributed species first reported from Pacific Costa Rica by Fonseca and Cortés (1998) .