Modifications on the antennae of Nomada fucata ♂ (a) (left antenna, dorsal), N. flavoguttata ♂ (b) (right antenna, ventral) and N. lathburiana ♂ (c) (left antenna, lateral). SEM micrographs. a1 weak elevation on flagellum 6 laterally. Scale unit: 0.1 mm b1 weak elevations on flagellum 4 ventrally. Scale unit: 0.1 mm c1 nodule on flagellum 9. Scale unit: 0.1 mm a2 pores and secretions on the elevation. Scale unit: 0.01 mm b2 pores and setae on the elevations. Scale unit: 0.01 mm c2 nodule covered with secretions. Scale unit: 0.02 mm.