CHAETOTAXY OF TERGITES IN THE ARCHAEOGNATHA (INSECTA) AND ITS TAXONOMIC SIGNIFICANCE

The chaetotaxy of the various types of setae of the tergites of Archae ognatha (Insecta) are described here for the first time. In particular , the presence or absence of lateral rows of spiniform setae on the va rious thoracic tergites and of groups of spiniform setae on the poster o-lateral parts of the abdominal tergites appear to be important for t he generic and suprageneric taxonomy of the group. Representatives of 33 of the 64 known genera of the Archaeognatha were examined. In addit ion, other types of tergal setae an briefly described. Two of these ar e present only in the first and second unsealed developmental stages. The specialised chaetotaxy (including scales) of the Archaeognatha is compared with that of other insects, especially the other ''Apterygota ''. The results are discussed from the phylogenetic point of view.