(a)–(d): Shape and function of the apical pedicle in attached species. Scale bar = 1 cm (= 0.5 cm in detail pictures). (a) Lepidoleptaena poulseni. NRM Br129751; Burgsvik, Öja parish; Hamra Formation; Pedicle length and thickness indicated by bryozoan overgrowth. (b)–(d) L. rhomboidalis. PMU G1054; Visby, Högklint Formation; section through open apical foramen showing scars after attachment of muscles within the pedicle tube (white arrow) and reconstruction of the intrapedicular muscle (PA) attaching to the ventral interarea (PD). DM is the diductor muscles. (e)-(f): Internal sealing of the apical foramen in free-lying species. (e) L. parvorugata. NRM Br138049a; Valleviken 1, Rute, Slite Group. (f) L. depressa depressa. NRM Br138045; Mulde Tegelbruk, Fröjel; Halla Formation. Both have covered the apical part of the muscle scars with thick secondary shell material.