Field biology of Zapriothrica sp. Wheeler (Dipt., Drosophilidae), a pest of Passiflora spp. of high elevation possessing long tubular flowers

Abstract

Abstract: Blooms of Hawaii's banana poka, Passiflora tripartita var. tripartita, grown at Ipiales, Colombia were found suitable for the completion of the life cycle of the fly Zapriothrica sp. The tubular flowers were an ideal habitat for the mating and reproduction of this minute Andean fly. Oviposition occurred only on immature flowers 30‐20 days from bud opening. Eggs hatched 10–13 days after oviposition. Larvae averaged 1.3 × 0.3 mm at hatching, and 15 days after hatching at the end of the third larva instar averaged 5.2 × 1.0 mm. The light‐brown pupa averaged 3.6 × 1.3 mm and required 40–45 days for completion of this stage. Adult flies averaged 5.1 × 1.3 mm and their life span was 7–10 days in captivity and 5–8 days in field cages. Mating was inside the flower tube and a minimum of five pairs of adults were required for copulation. Other Passiflora spp. of high elevation with tubular flowers were host of the insect. However, campanulate flowers, e.g., P. edulis, P. ligularis, and P. alnifolia did not elicit any response whatsoever for feeding, aggregation, mating or oviposition. The dropping of immature flower‐buds caused by this insect in P. tripartita v. mollissima and P. tripartita v. tripartita was 60–80% in Colombian and Ecuadorian curuba farms with high pest populations.