Certesella murrayi (Wailes, 1913)

Diagnosis: Shell wide piriform in broad view, compressed with a well-developed, but short subcylindrical (ovoid in cross-section) neck, and a short hollow keel at the base of the neck. Aperture with a thick organic rim. Two lateral depressions at the junction of the neck and the main part of the shell, each with a large central pore connecting the two sides of the shell by an internal tube. Conical teeth present on the inner surface of the neck (invisible on the illustration, but indicated in the original description).

Measurements. Shell length 120—136 μm; width 95—100 μm; aperture 30–35 μm.

Ecology: Sphagnum and other mosses.

Geographical distribution: South-America: Argentina, Brazil, Chile. Possibly a South American endemic, like C. australis.

Remark: Certesella murrayi is very similar in appearance to C. martiali. The two species differ mainly in size.