Chrysosphaerella coronacircumspina Wujek & Kristiansen

(Fig. 1B)

Chrysosphaerella solitaria Preisig & D.J.Hibberd, Plant Systematics and Evolution 129: 136 (1978).

DISTRIBUTION. — Widely distributed (Kristiansen 2000).

REMARKS

This species is easily distinguishable from other Chrysosphaerella species by its spine-scales in which the secondary base-plate is attached directly to the primary base-plate.

We observed C. coronacircumspina during encystment. The stomatocyst was spherical (diameter 11.6 µm) with psilate surface. The collar is cylindrical (diameter 4.19 µm, height 0.8 µm). The pore morphology is unknown.

Preisig & Takahashi (1978) illustrated the stomatocyst of C. solitaria Preisig & E.Takahashi but the pore and collar remained not visible. According to these authors the dimensions of stomatocysts were 13-14.7 µm. Balonov (1980) also observed spherical stomatocysts (diameter 12.3-14.8 µm) but they lacked the collar. Recently, Firsova et al. (2017) revealed that stomatocyst 156 Zeeb & Smol 1993 is produced by C. coronacircumspina .