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 gosnoldi E. Cutler, 1981 Material examined . Bahía Chatham, 60 m , 7 April 2008 , 3 specimens , specimen removed from shell approximately 25 mm long; Bahía Wafer, 20 m , SCUBA , 10 April 2008 , 2 specimens , one approximately 12 mm . Additional material . Bahía Chatham, 16m , 6 April 2008 , 4 specimens , approximately 10–20 mm ; Isla Manuelita, 28–51m , 17 October 2007 , 2 specimens , approximately 20 mm ; Punta Ulloa, maërl, 39–43m , 17 October 2007 , 2 specimens , approximately 20–25 mm . Description : The anal shield has irregularly arranged units that give it the appearance of being grooved. Rings of bidentate hooks distally on the introvert followed by numerous scattered pyramidal unidentate hooks with a dark border. The retractor muscles are attached posteriorly at the caudal shield and the nephridia are approximately 90% of the body length. Habitat. Subtidal, sand bottom, marl (rodolith beds), shells, 16- 60m . Remarks. These specimens were deeply coiled in small rissoid gastropod shells. This is the first record for this species from Costa Rica . Distribution. This species has been previously reported from gastropod shells from Cape Hatteras to Brazil ( Cutler 1994 ).