The tentorial complex of the Sphaerotheriida, 3D visualization. GREY = Head capsule; BROWN = mandible; ORANGE = tentorium; YELLOW = nebententorium; OLIVE = außententorium. A–D Arthrosphaera brandtii (Humbert, 1865), ZFMK MYR6265 E, F, I, J Sphaeromimus kalambatritra, CASENT 9058301 G, H Zoosphaerium bemanevika Sagorny & Wesener, 2017, ZFMK MYR6144. A tentorial complex and its association with the mandibular gnathal lobe and the head capsule of A. brandtii, dorsal view B same as A frontal view C tentorial complex of A. brandtii, frontal view D same as C medial view, with rotated epipharyngeal bar E tentorial complex of S. sp., frontal view F same as E medial view, with rotated epipharyngeal bar G tentorial complex of Z. bemanevika, frontal view H same as G medial view, with rotated epipharyngeal bar I tentorial complex and its association with the mandibular gnathal lobe and the headcapsule of S. sp., dorsal view J same as I, frontal view. Abbreviations: at = antennal socket; aut = mandibular gnathal lobe sclerite (außententorium); co = condylus of mandible; e1 = lateral projection of epipharyngeal bar; e2 = medial projection of epipharyngeal bar; eb = epipharyngeal bar; et = external tooth; h1 = projection of hypopharyngeal bar; hb = hypophayrangeal bar; hc = head capsule; ilp = projection arising from incisura lateralis; it = internal tooth; mp = molar plate; nt = nebententorium; pl = pectinate lamellae; pp = posterior process.