Surirella stalagma
Hohn and Hellerman 1963 Category: Surirelloid
BASIONYM: Surirella stalagma Hohn and Hellerman 1963
LM scalebar = 10 µm = 80 pixels.
Observations
Contributor: Jonathan English - March 2011
Length Range: 11-16 µm
Width Range: 5-7 µm
Striae in 10 µm: 55
Description
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.
Original Description
Basionym: Surirella stalagma
Author: Hohn and Hellerman 1963
Length Range: 13-14 µm
Width Range: 6.2 µm
Striae in 10 µm:
Original Description
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.
Original Images
Cite This Page:
English, J. (2011). Surirella stalagma. In Diatoms of the United States. Retrieved May 25, 2013, from http://westerndiatoms.colorado.edu/taxa/species/surirella_stalagma
Species: Surirella stalagma
Contributor: Jonathan English
Reviewer: Rex Lowe
Image Credit: Jonathan English, Marina Potapova
- Valves small
- Valves heteropolar
- Costae not visible in LM
- Fibulae short, wide
- Low keel, wider than the mantle
Valves are small and heteropolar, 11-16 µm long by 5-7 µm wide. The foot-pole is capitate, while the head-pole is rounded. The costae are numerous, 55 in 10 µm, so they are only visible in SEM. The fibulae are short and wide, with a density of 8-10 in 10 µm. The keel is low, and broad compared the the mantle.
Compare
Surirella stalagma is differentiated from most other species of Surirella by its small size and capitate footpole. While the costae of S. minuta are visible using LM, the costae of S. stalagma are not visible, except with SEM. The costae of S. suecica may also not be apparent in LM. The fibula of S. suecica, however, arise from 2-4 costae instead of 1, and are shorter and wider in S. stalagma than in S. suecica. In addition, the keel of S. stalagama is wider than the mantle, while the keel of S. suecica is more narrow than the mantle.
Surirella suecica
Surirella minuta
Citations
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.
Links & ID's
Index Nominum Algarum (INA)
California Academy of Sciences (CAS)
North American Diatom Ecological Database (NADED)
NADED ID: 65045