Morphometric analyses of Palaearctic Dasineura and Jaapiella species (Diptera : Cecidomyiidae, Oligotrophini) developing in flower heads of Asteraceae, with description of four new species

Morphometric studies of males and females of species of oligotrophine Cecid omyiidae reared from flower heads of seven genera of Asteraceae (Centaurea, Cirsium, Hieracium, Hypochoeris, Inula, Reichardia, and Saussurea) demonst rated, despite great overall morphological conformity, many instances of st atistically significant differences between the species. Measurement values of structures in adult specimens were corrected for allometric deviations according to a procedure representing a further development of a method pre viously used for taxonomic purposes in gall midges. No galls produced by th ese midges have been observed. Beyond adults, also pupae and larvae were st udied. Two Dasineura species and several Jaapiella species are represented. Four new species are described: Dasineura vulgatiformiae Sylven, Jaapiella hypochoeridis Sylven, Jaapiella pilosellae Sylven, and Jaapiella reichardi ae Sylven.