Immature stages of Meiosimyza Hendel 1925 and related genera (Diptera, Lauxaniidae)

The immature stages of Holometabolan insects can provide valuable data both for taxonomy and phylogeny, but they are well known only for a negligible proportion of the described species. Scanning electron microscopy (SEM) analysis of all preimaginal stages of the lauxaniid species Meiosimyza decempunctata (Fallen 1820), M. platycephala (Loew 1847), M. rorida (Fallen 1820), M. subfasciata (Zetterstedt 1838), Tricholauxania praeusta (Fallen 1820) and Aulogastromyia anisodactyla (Loew 1845) is presented for the first time. Detailed images of eggs and all three larval instars are provided along with illustrations of the cephaloskeleton and photos of puparia. The egg is rather simple, white, with developed longitudinal ridges. The body integument of all larval instars is smooth and uniform across species. The cephaloskeleton is slender; the mouth hooks are parallel, subhypostomal sclerites are arched and fusing to a ventral bridge. The puparium is brownish, oval, without calcareous deposits. Generally, the morphology of larvae and puparia is very conservative. On the other hand, the eggs show considerable degree of interspecific variability.