We report a case of a suspected intestinal myiasis of a child from Southeast Argentina. Diptera larvae were sampled by a physician from the nappy worn by the child and submitted for examination and identification to the Laboratorio de Artrópodos (Universidad Nacional de Mar del Plata). Based on diagnosis of the anterior and posterior spiracles and mouthparts, the larvae were identified as the false stable fly Muscina stabulans (Fallén, 1817) (Diptera: Muscidae). A comparison of diagnostic characters between Argentinean and European third instars of this species is presented. Muscina stabulans is a prevalent species in the district of General Pueyrredón, Buenos Aires province, where the case occurred. Its abundance in the area coincidentally peaked at the time of the infestation. This is the 1st report of M. stabulans as a suspect of intestinal myiasis for the whole of the southern cone of South America (Chile and Argentina).
Keywords: accidental myiasis; baby host; dipteran; maggots; muscinae; toddler.