Hyalosphenia spec.

Diagnosis: Shell transparent, colorless, yellow or brown, elongated oval with a truncate, more or less straight or slightly curved pseudostome; aperture nearly as broad as the shell; fundus broadly rounded or a little constricted; surface finely granulated; plasma usually partly filling the shell, with some epipodia; nucleus globular with a small nucleolus.

Dimensions: About 100-120 µm.

Habitat: In the ooze of a river near Oberndorf/Bremen in Germany. Observed food: mainly diatoms.

Remarks: This species was discovered by Steffen Clauss, Germany, who published some photomicrographs in a German internet forum. According to his description he found about 50 specimens pro ml. ooze.

This species resembles H. penardi, but the latter is much larger (180 µm), has a nearly semi-circular aperture (“stark gewölbt”) and has no scale structure.