Figure 1.

Hydrophobic leg hairs are bristles. Three Gerromorpha species have been investigated: Gerris buenoi (a), Microvelia americana (b) and Mesovelia mulsanti (c–f). All species have hydrophobic bristles on legs that are clearly visible using SEM (a–c). In Me. mulsanti, high magnification pictures show the socket cell at the base of the bristle, and the ridges of the bristle resulting from the inner actin organization (d–f). In Me. mulsanti, TEM pictures show that bristles are innervated structures with an outer dendritic segment underneath each single bristle (d,e). (g) Schematic representation of a bristle and associated structures. cu: cuticle, ds: dendritic sheath, EDM: electron-dense materials, od: outer dendritic segment, mt: microtubule, s: shaft.