Fig. 29 in Early-middle Cambrian stratigraphy and faunas from northern Siberia

Fig. 29. Pelagiellid mollusc Aldanella sibirica Parkhaev and Karlova, 2011, from the lower Cambrian Tyuser Formation, lower reaches of the Lena River (A) and Erkeket Formation, Khorbusuonka River (B), Siberia, Russia; samples 21/21 (A) and 11/16.1 (B). A. Phosphatised shell, SMNH Mo194736. A1, A2, enlargements showing protoconch; A3, adapical view; A4, oblique adapical view. B. External mould, SMNH Mo194737, with sculpture of the shell surface. Scale bar: 250 µm (A3, A4), 125 µm (A1, A2, B).