Nymphal and adult cephalic chaetotaxy of the Cydnidae (Hemiptera: Heteroptera), and its adaptive, taxonomic and phylogenetic significance

Cephalic chaetotaxy of nymphal and adult stages of species from all the subfamilies of Cydnidae s. str. (sensu Froeschner, 1960 and Lis, 1994), namely Garsauriinae, Cephalocteinae, Cydninae, Sehirinae, and Amnestinae, was studied. Two types of setae, primary and secondary, are described, and changes they undergo during ontogeny reviewed. The adaptive, taxonomic and phyloge- netic significance of the cephalic setae in the Cydnidae s. str. is discussed. A ground-plan of the original cephalic chaetotaxy of the family, and its evolution within the family Cydnidae s. str. are proposed.