3D reconstruction of the basal part of the terebra of Habrobracon hebetor composed of the 2nd valvulae and the paired 1st valvulae, based on a semithin section series (600 nm thickness a lateroventral aspect b lateral aspect c dorsal aspect d ventral aspect). The duct of the venom gland enters dorsoproximally on the left side only. The two ligaments connect the 2nd valvula to the anterior parts of the 2nd valvifers (not visible in these images). The black circle (b) indicates the rotation axis of the basal articulation. The lines of the processus articularis and processus musculares (b) point to their presumed position according to the results of van Meer et al. (2020). The peak-like structure at the anterior end of the 2nd valvula (red arrow in a, b) is part of the processus musculares. There are two openings (black arrows in a, c) at the proximal side of the bulbs. The duct of the venom gland enters on the left side only. Abbreviations: 1vv = 1st valvula; 2vv = 2nd valvula; blb = bulb; ec = egg canal; lg = ligament; pa = processus articularis; pm = processus musculares; vd = duct of the venom gland.