Fig. 3

SR-μCT images of the terebra of Venturia canescens. a 3D visualization of the whole terebra in the metasoma. b Virtual cross sections through the terebra from proximal to distal. Proximal (blue); every 65 μm, a cross section is displayed because of strong morphological changes such as the bulbous proximal end of the 2nd valvula. According to the limited morphological changes along the longitudinal axis, for the next part (green), a cross section is shown only every 260 μm over the next 3380 μm. The most distal 900 μm (red) shows, once again, large morphological variations such as the spindle-shaped cavity formed by all three valvulae; therefore, a cross section is shown every 65 μm. The arrows indicate the undivided distal parts of the 2nd valvula. Abbreviations: 1vv, 1st valvula; 2vf, 2nd valvifer; 2vv, 2nd valvula; 3vv, 3rd valvulae; blb, Bulb; ec, Egg canal; lf1, Longitudinal flap of the 1st valvula; nm, Notal membrane; ssc, Spindle-shaped cavity; trb, Terebra