Trachelocorythion spec.

Diagnosis: Shell ovoid, compressed, with a broad slightly curved aperture without neck or collar; pseudostome slit shaped, one lip c. 5 µm longer than the other one; shell composed of oval siliceous scales of more or less equal size; apertural scales not denticulated; nucleus relatively large, nucleolar material finely granulated; filopodia not observed.

Dimensions: Length 78 µm, nucleus c. 18 µm (n=2).

Habitat: Freshwater, pond in city center of Yangshuo, China. Observe food: green algae.

Remarks: This is a larger species than the one described by Penard. It differs from T. pulchellum by its larger size and the structure of the nucleus.

It could also be a Placocysta species.