A study on morphology of immature stages of Diplonevra peregrina (Wiedemann) (Diptera: Phoridae).

Morphology of all larval instars and puparium of Diplonevra peregrina, a most common phorid fly species indoors in China, is presented using scanning electron microscopy. The first instar larva was composed of 12 segments, each of segments 3-11 with six spicate tubercles situated dorsally, dorsolaterally, and laterally in transverse row. The dorsal tubercles were much longer than the laterals and dorsolaterals. Antennae and maxillary palp complex were visible. The caudal segment was margined by six long, stout tubercles covered by numerous long bristles at the base through the apex. Two slits could be seen at the posterior spiracle. Besides the presence of anterior spiracle, the tubercles of second instar became more stout than those of first instar and were covered by numerous long bristles from the base to top. The posterior spiracle contained four slits. Third larval instar was similar to second instar. The bubble membrane comprised of clusters of small spines presented at the segment 5 of third instar larvae. Puparia showed a retracted cephalic region and a pair of pupal respiratory horns on the dorsum.