Hohn and Hellerman 1963 Category: Surirelloid
BASIONYM: Surirella stalagma Hohn and Hellerman 1963
Contributor: Jonathan English - February 2011
Length Range: 11-16 µm
Width Range: 5-7 µm
Striae in 10 µm: 55
The valves are heteropolar, 11-16 µm long by 5-7 µm wide. The head-pole is broadly rounded while the foot-pole is capitate. The keel is low and is slightly wider than the mantle face. The apical axial line is visible in the LM while the costae are not. In the SEM the the costae have a density of 55 in 10 µm. Between the costae are 2-3 rows of slit-shaped areolae. The extremely abreviated fibulae, in a density of 8-10 in 10 µm, are visible in the LM and arise from 2-4 costae. The portulae have 2-4 costae entering them. The rows of areolae are interrupted between the fibulae before they enter the portulae.
Basionym: Surirella stalagma
Author: Hohn and Hellerman 1963
Length Range: 13-14 µm
Width Range: 6.2 µm
Striae in 10 µm:
Valve oval, basel end with capitate protuberance; alae small but distinct, 8-10.10 µ; alar canals not well defined; structure very delicate, striae invisible; length 13.0-14.0 µ, width 6.2 µ.
Hohn, M.H. and Hellerman, J. (1963). The taxonomy and structure of diatom populations from three Eastern North American rivers using three sampling methods. Transactions of the American Microscopical Society 82(3):250-329.