Length:22.5

Width:5.5-6

Striae:24-26

Puncta:6-7

Collection 1159a

J.W. Bail., Smithsonian Contr. Knowl., 7(3): 9, figs. 1-2, 1854 (accepted for publication, 1853). (Patrick and Reimer 1975).

Synonyms (Patrick and Reimer 1975)

Ecology

Based on limited data, it appears that this taxon prefers water of high conductivity. (Patrick and Reimer 1975).

Length is 18-67 micrometers (Patrick and Reimer 1975).

Breadth is 5-10 micrometers (Patrick and Reimer 1975).

Striae range is about 20 in 10 micrometers (Patrick and Reimer 1975).

Costae across the valve, 2-4 in 10 micrometers (Patrick and Reimer 1975).

Short costae, 3-4 in 10 micrometers (Patrick and Reimer 1975).

Other morphological features:

This taxon is distinguished by the usually alternate short and long costae and by the shape

of the valve. The costae occur in two types: those that extend across the valve and those

that extend only to the edges of the ocelli, which are in the craticula plate. Valves oblong

with rounded apices. Striae distincly punctate. (Patrick and Reimer 1975).