Pseudocorythion undulacollis Chardez & Thomas, 1980

Diagnosis: Shell consists of two different sections: a large funnel-shaped collar around a circular aperture and an elongated ovoid body with or without a terminal spine; in cross-section elliptical. Shell covered with rounded idiosomes, regularly arranged. The border of the collar is finely undulated. A number of small striations extend from the border towards the aperture for about 1/3 of the diameter of the collar. Just as the body, the collar is ornamented with idiosomes, but these are slightly oval and arranged in circles.

Dimensions: Chardez and Thomas (1980): Shell length 41—52 µm; diameter 10—180 µm; collar 21—28 µm.

Ecology: Marine.

Geographical distribution: France, Atlantic coast.