Almost stiaight valve with ventral margin, slightly concave in the middle. Main body of the valve and apices not clearly differentiated. Raphe only slightly curved up on the ventral margin at the central nodule towards dorsal margin. Sometimes raphe is only visible in the valve view of the central portion. Closely related to E. adnata but E. intermedia usually has more distant costae, fewer rows of alveoli in ten micrometers, and the rows of alveoli and costae are parallel to each other. Costae ends in girdle view capitate.
(Patrick and Reimer 1975).