The Pupal Pigmentation Pattern and Pupal Development in the Species of Aphytis Howard (Hymenoptera: Aphelinidae)

Species identification of on the basis of adult morphology is extremely difficult, especially in the group, with several cryptic species. Pupal pigmentation could be used as one of the taxonomic characters for species, and in some instances, pupal pigmentation actually provided the first clue to the distinctness of cryptic species. The present study investigated the full-grown larvae or younger pupae of species, and pupal pigmentation and pupal development were observed and photographed. Four characteristic pigmentation patterns of pupae were summarized including: entirely yellow, partly dark brown, entirely or predominantly black, and partly black. The species in the and groups, and some unassigned species, generally have entirely, or predominantly and or partly black pupae. The species in the , , and groups generally have the pupae entirely yellow. The species of the group have the pupae both entirely yellow, e.g., , and partly dark brown pupae, e.g., , and . The pupae of species in this study had a developmental duration of about 5-8 days at 27 ± 1 °C, 70 ± 5% RH and a photoperiod of 10L: 14D. It was found that the pupal skin was always melanized at the beginning stage, generally in the first day, among the pigmented pupae of species. As development continued, the pigmentation became darker and the eye colour changed from pale red/brown to green. No significant intra-specific variation in pupal colour pattern was detected despite relatively high numbers of specimens examined, many from multiple, and different, origins. Overall, our study indicates that pupal pigmentation could be more helpful in species identification of .