From larva to puparium: Larval–pupal parasitoid strategies of Figitidae associated with Diptera

Larval–pupal parasitism represents a distinctive developmental strategy in which the parasitoid attacks a living dipteran larva, develops internally while the host continues feeding and growing, persists through host pupariation, and emerges later from the puparium. This integrative descriptive review synthesized biological, ecological, and developmental patterns of Figitidae associated with Diptera, emphasizing the distinction between the stage attacked and the stage of adult parasitoid emergence. The analysis considered parasitoid identity, host identity, substrate, larval habitat, oviposition, endoparasitic development, continued host growth, pupariation, parasitoid maturation, host mortality, and emergence outcome. Records from coprophagous, synanthropic, decomposing-organic, and fruit-associated systems were organized around the sequence of larval host location, host recognition and acceptance, oviposition, internal development, pre-puparial movement, puparium formation, and adult parasitoid emergence. Focal taxa included Ganaspis pelleranoi (Brèthes, 1924), Leptopilina boulardi Barbotin, Carton & Keiner-Pillault, 1979, Neralsia splendens (Borgmeier, 1935), Paraganaspis egeria Díaz, Gallardo & Walsh, 1996, Triplasta atrocoxalis (Ashmead, 1895), and Triplasta coxalis (Ashmead, 1895). The synthesis showed that emergence from a puparium should not automatically be interpreted as evidence of pupal parasitism because the biological association may begin substantially earlier in the larval stage. Substrate type influences where hosts are encountered, how parasitoids search for larvae, and where parasitized hosts subsequently pupate. The same larval–pupal strategy can therefore occur across ecologically contrasting environments without implying identical host-use mechanisms. By separating larval attack, host continuation of development, pupariation, and final emergence, the review provides a coherent framework for interpreting Figitidae–Diptera associations and for avoiding misclassification of larval parasitoids as true pupal parasitoids. This framework also supports clearer interpretation of host mortality, parasitoid production, and developmental success in ecological and biological-control studies. It further highlights the importance of preserving host, substrate, and emergence information together when reconstructing parasitoid life histories from field collections and laboratory rearing records across diverse environments.