Fig. 3 a–d

Structures of the male genitalia of Pediculus humanus capitis studied under SM, confocal laser scanning microscopy (CLSM), and SEM. a Ventral view of the genital chamber of a male at rest (SM microphotograph) showing the basal plate (bp), the contracted vesica (cv), the support of the penis (sp), and the penis, though the latter is less evident. b Male at the initial phase of copulation under CLSM. The relaxed genital opening, the mesomeres (m), and the parameres (pr) can be observed as a result of the position of the dilator. Scale 50 µm. c Detail of the position of the dilator during copulation, as seen under SEM. d Articulation of the parameres and the basal plate (bottom arrow), attachment of the mesomere to the vesica stem (top arrow), the vesica stem, and the vesica, as seen under CLSM. Scale 100 µm. For other abbreviations, see Figs. 1 and  2