Parvicorbicula pedunculata

Cells solitary, cells when dried 4x3 microns, the flagellum 4-6 microns long. Lorica 20-26 microns long consisting of a chamber, interpretable as single, surmounting a relatively massive stalk. Chamber, conical,13-14 microns long, maximum width 8-12 microns, composed of 9 or 10 longitudinal costae, each containing three costal strips, continuous to base of chamber where they unite in groups with the top of the stalk. Two transverse costae on anterior part of lorica both with" same number of costal strips as there are longitudinal costae. Each component strip of anterior edge forming a T-join with the appropriate longitudinal costa and each component strip of the middle transverse costa exactly bridging the space between adjacent longitudinal costae. Arrangement of transverse costae at posterior end of chamber variable, usually consisting of two or three bands of somewhat ill-defined costae. Anterior band usually located at or above join between posterior and middle costal strips of each longitudinal costa. Stalk compound, 6.5-10 microns long, of uniform width throughout and consisting of 4-6 parallel arrays of linearly attached longitudinal strips.