THE NAUTILUS 123(3):159–165, 2009 Page 159 Feeding behavior of Adelomelon ancilla (Lighfoot, 1786): A predatory neogastropod (Gastropoda: Volutidae) in Patagonian benthic communities Gregorio Bigatti Carlos J.M. Sanchez Patricia Miloslavich Pablo E. Penchaszadeh Centro Nacional Patago´nico Antelo Departamento de Estudios Museo Argentino de Ciencias CENPAT – CONICET Museo Argentino de Ambientales Naturales (MACN-CONICET) Boulevard Brown s/n Ciencias Naturales Universidad Simo´n Bolı´var and U9120ACV Puerto Madryn (MACN-CONICET) Apartado Postal 89000 Departamento de ARGENTINA and Caracas 1080 Biodiversidad Facultad de
[email protected] Departamento de VENEZUELA Ciencias Exactas y Naturales Biodiversidad Facultad de Universidad de Buenos Aires Ciencias Exactas y ARGENTINA Naturales Universidad de Buenos Aires, ARGENTINA ABSTRACT In the gulfs of northern Patagonia, this species inhabits mixed gravel and sand bottoms, and is easily collected by Adelomelon ancilla, a volutid commonly found in shallow water SCUBA at depths of 5 to 20 m, during low tide, and near in northern Patagonia, is a top predator in the benthic commu- the shore. Despite its commercial importance as a new nities of this region. This species presents an anemone (Antholoba achates) epibiosis that may protect it from preda- fishery resource, A. ancilla has not been well studied, tors. Adelomelon ancilla captures prey by tightly engulfing it with research on this species being limited to descriptions with the foot, and ingests them, generally alive, after narcotiz- of egg capsules and embryology (Penchaszadeh and ing their muscles. A narcotizing substance, produced by the De Mahieu, 1976; Penchaszadeh et al., 1999; Penchaszadeh accessory salivary glands, is released through the proboscis and Miloslavich, 2001; Penchaszadeh et al., 2006), and into the prey while the latter is tightly enveloped within the to reproductive biology and oviposition (Penchaszadeh foot, allowing for prey narcotization.