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Genus Certesella

Shell is pyriform elongated or flask-shaped, compressed in cross section, neck with parallel sides, organic apertural rim. The development of the neck varies among species from slightly to well differentiated. The main characteristics of the genus are the presence of two lateral depressions with large central pores connected by two tubes located at approximately 2/3 of the distance between the fundus of the shell and the aperture, and the presence of internal teeth on the neck giving punctuated impression. Shell composed of collected euglyphid idiosomes in an unstructured cement, transparent. Type species: Certesella martiali (Certes, 1889)