The immature stages oí Hemilucilia segmentaria (Fabricius, 1805) (Diptera: Calliphoridae) are described. Egg morphology and structures such as the cephalopharyngeal skeleton, anterior and posterior spiracles, and the dorsal spines between the prothorax and mesothorax from first, second and third instar larvae are characterized, using light and scanning electron microscopy. This species is abundant in Neotropical forests and, because of its necrophagous behavior, is of substantial medico-legal importance for estimating the postmortem interval in criminal investigations. Information presented herein may be useful to differentiate among eggs and larvae of closely related species and to supplement the database for blowfly identification