Description of Acanthocorbis tintinnabulum:
Lorica consisting of a single bell-shaped chamber, 6.5 microns long, 4.5 microns in diameter and 12-14 longitudinal costae extending beyond the chamber to form spines, 5-5.5 microns long. The spines are tipped with a small claw. The overall length of the organism is 11-12.5 microns. The arrangement of costae in the lorica chamber is complex with about 16 longitudinal costae and about 40 costal strips roughly sprially arranged but with a distinct anterior transverse costa. The anterior longitudinal costae are 6-7 microns long, although on some organisms these costal strips are as short as 3.6 microns. They are rounded at their posterior end and taper from about 90nm to 60nm in diameter along their length and bear a claw on their anterior end. These costal strips extend about 75 % of their length beyond the lorica chamber. The costal strips of the lorica chamber are about 100 nm in diameter, about 4 microns long and have rounded ends.