Scale Bar = 10 micrometers.

Valves are linear with blunt rounded apices lending the diatom a roughly rectangular appearance. Stria are very broad and widely spaced. Striae near central area are reduced in length forming a small hyaline area. Striae are slightly radiate near central area gradually shifting to slightly convergent at apices. Raphe deflects to one side at central area and sharply to the opposite side at the apices. Specimens ranged in size from 38-43 micrometers long and 9-11 micrometers wide. Stria were 5-6 per 10 micrometers. The bottom specimen is laying in girdle view. The markings on the girdle are quite common in the genus Pinnularia.