Description
Large cell-sized species, with round and broad bodies in ventral and
dorsal views (Figs 3a–b, d–e, i–j, and l), strongly dorsoventrally
compressed (Figs 3c, k, and 4k). The epitheca abruptly transitions into
a long and slender apical horn (Figs 3a–b, e, h, i–j, and 4i–j),
which is strongly tilted towards the ventral side (Figs 3c, k, and 4k).
The 1’ plate is orthogonal, wide, and almost symmetrical, with extended
proximal margins (Figs 3b, e, g, j, and 4i). The plate 2a is
asymmetrical and pentagonal, shifted to the left (Figs 3h and 4j, l).
The plate 3a is asymmetrical and pentagonal, about 2.5–3 times the area
of 1a, which is quadrangular, and the plate 4” is about double times
wider than long (Figs 3h and 4j, l). The cingulum is very narrow,
displaced, descending by about 1.5–2.0 cingular widths, not excavated
(Figs 3a–b, e, i–j, and 4i), strongly inclined relative to the
equatorial plane of the cell (Figs 3c, k, and 4k), and bears smooth
lists (Fig. 4e). The sulcus is deep and very narrow in the anterior
part, and reaches the antapex, with lists (Figs 3a–b, e, i–j, and 4i).
The hypotheca possesses two long antapical horns (the right one is
longer than the left), which are slender, pointed, almost parallel, and
nearly equal in length to the apical horn (Figs 3a, c, e, i, and 4i–k).
The thecal surface is smooth, with pores (Figs 3f–g). Dimensions:
length 215.6 ± 2.7 µm (min. 210 µm, max. 220 µm, n = 26), width 115 ±
2.9 µm (min. 110 µm, max. 120 µm, n = 27), and depth 40.6 ± 1.3 µm (min.
38 µm, max. 42 µm, n = 22).