Pterocystis caudata Udalov et Zlatogursky, 2023
  
Diagnosis: Cell body diameter usually 10–20 μm. Axopodia 2–3 cell diameters long, granulated. Plate-scales oval, sometimes slightly sharpened towards one end with parallel edges, axial thickening and thin marginal border, typically 2–3.5 μm long and 1–1.6 μm wide. Spine-scales (2.5–7 μm long) with elongated shaft and funnel-shaped base, outlined with marginal border. Funnel with circular or drop-shaped outline, separated from the shaft indistinctly but noticeably. Shaft with midrib going from the funnel up to scale tip. Funnel with short (not longer than its own diameter) bulbous stalk. Proximal part of shaft and funnel with some amount of slits parallel to scale axis. Some spine-scales with rudimental shaft or without shaft.

Ecology: Marine waters. Bay of Villefranche, Mediterranean Sea, France.

References: Udalov, I., Gavrilov, A., Kudryavtsev, A., Volkova, E., Zlatogursky, V., 2023. Pterocystis caudata sp. n. – the new species of centrohelid heliozoans (Pterocystidae, Pterocystida, Centroplasthelida) from the Bay of Villefranche, France. Protistology 17. https://doi.org/10.21685/1680-0826-2023-17-2-1