FIGURES 18–23 in Validation of Heterocerus heydeni Kuwert, 1890 based on morphology and DNA barcoding, with notes on the problems of classification of the Heteroceridae (Coleoptera)

FIGURES 18–23. Male genitalia of Heterocerus spp. 18—aedeagus H. heydeni, ventrally; 19—tegmen apex H. heydeni, dorsally; 20—tegmen sclerotization H. heydeni, dorsal; 21—aedeagus H. flexuosus, ventrally; 22—tegmen apex H. flexuosus, dorsally; 23—tegmen sclerotization H. flexuosus, dorsal. On Figs. 18 & 21 most of the sclerites and membranes connecting the lateral lobes of tegmen and penis base are omitted. Scale bar = 0.1 mm.