Descripción del primer caso teratológico en un ejemplar de Esphalmenus silvestrii (Borelli) (Dermaptera: Pygidicranidae) de Isla Magdalena, Chile

First teratological case in the earwig Esphalmenus silvestrii (Borelli, 1902) is reported. The case belongs to an atrophy and oligomery unilateral with anarthrogenesis in the mesothoracic right leg. The case is discussed and illustrated. Additionally, this is the first record of E. silvestrii in Magdalena Island, Magellanes Region, Chile.