Light (A, C) and scanning electron (B, D-I) micrographs of Longinebela penardiana. (A, B) View of many specimens to illustrate variability in shape and size of the shell. (C) View of live specimen showing granular cytoplasm, pseudopodia and epipodes. (D) Broad lateral view to show general shape and arrangement of shell-plates. (E) Lateral view. (F) Apertural view. (G) Detail of shell surface showing shape and arrangement of shell-plates. (H) Broad lateral view of apertural region. (I) Close up view of aperture to show aperture outline and collar of organic cement.