(A) Light micrographs. (B–L) TEM micrographs. (A) Whole valve. (B and C) Complete valve of different shapes. (D) Detail of the central nodule and striae with a row of poroids split in several sectors. (E) Apical part of a valve. (F) Central part of a valve showing the central nodule, the poroid arrangement, and the proximal and distal mantles. (G) Detail of the poroid structure. (H and L) Detail of the valvocopula. (I–K) Different cingular bands. (A–C, F–H, J, and K) Strain Ner-F1. (D) Strain Ner-J6. (E, I and L) Strain Ner-G4.
