Haeckel
Spirocyrtis scalaris group?
Thin-walled shell composed of up to 8 joints with a typically angular outline increasing step-wise in width toward the base. Pores on post-thoracic segments quadrangular, arranged in very regular transverse rows. Shell height: 100-200 µm.
Ref.: Nigrini (1967), Petrushevskaya (1971a).