Fig. 7 in Conellae, enigmatic structures on cephalopod shells -shapes, distribution, and formation

Fig. 7. Sediment-filled conellae on phosphorite internal moulds of Late Oxfordian Amoeboceras serratum (Sowerby, 1813) (RUB-Pal 7-11293, body chambers) from Rybaki locality in Moscow region, Russia. Group of conellae, note the small gap between conellae and internal mould (A1), conella with irregular outline showing a microboring, conella partially covered by nacre tablets suggesting that the conellae formed within the shell, was temporarily hollow and subsequently filled with sediment (A3,A5), framboid pyrite within the sediment fill of conellae (A4), matrix rich in radiolaria (so far unidentified) (A6).