Light (A-C) and scanning electron (D-I) micrographs of Tracheleuglypha dentata. (A, B) View of many specimens to illustrate variability in shape and size of the shell. (C) View of live specimen showing granulated band in the central region of the cell and large nucleus with many nucleoli, placed posteriorly; (D, E) Broad lateral view of two individuals to show general shape and regular arrangement of shell-plates. (F) Apertural view. (G) Close up view of aperture illustrating its shape, arrangement of apertural-plates and collar of organic material. (H) Lateral view of apertural region showing tooth-like structure of the organic collar (I) Detail of shell surface to show overlapping shell-plates.