Octopyle stenoza group?
Shells with 2 systems of latticed girdles (as described for the diagnosis of the family, Family Pyloniidae) and large gates (P. clevei intro). Major diameter: 100-250 µm. Some authors (e.g., Benson, 1966; Nigrini and Moore, 1979) recognize 2 species within this group (?): Tetrapyle octacantha Muller and Octopyle stenozona Haeckel; while others (e.g., Welling, 1997) consider Octopyle stenozona as a rare tropical end member variant of Tetrapyle octacantha (the wo froms were found to covary in tropical plankton).
According to Benson (1966), Octopyle stenozona is distinguished by its very narrow second transverse and lateral girdles, short saggital axis, generally quadrangular outline, and the presence of 2 heavy polar beams which occupy the principal axis.
Ref.: Nigrini and Moore (1979).