The third instar larvae of Xyloryctes furcatus Burmeister from Hidalgo, México and X. lobicollis Burmeister from Chiapas, México, are described. Drawings of diagnostic structures and a key to the third stage larvae of Xyloryctes jamaicensis (Drury), X. thestalus Bates, X. furcatus and X. lobicollis, are included.