Rearing and observation of immature stages of the hoverfly (Diptera, Syrphidae).

Background: The hoverfly Microdon (Chymophila) katsurai Maruyama et Hironaga 2004 was speculated to be a myrmecophilous species associated with the ant based on observations of adults near the ant nest. However, there have been no reports regarding the observation of immature stages of this species in association with .

New Information: For the first time, we found three larvae inside a nest and conducted rearing experiments on the larval . workers did not show any inspection or attack behavior against the larvae under rearing conditions, suggesting that larvae can survive inside a nest. Although no predatory behavior by the larvae was observed, all the larvae pupated and emerged in a rearing environment. The dorsal surface of the larval has a distinct pale green color with a uniform reticular structure. The puparium of shows several morphological features that are characteristic of the subgenus . We conclude that is likely a myrmecophilous species that utilizes as a specific host and that classification of based on puparium morphology is concordant with that based on adult morphology.