Psammothidium pennsylvanicum
Potapova 2012 Category: Monoraphid
BASIONYM: Psammothidium pennsylvanicum Potapova 2012
LM scalebar = 10 µm = 80 pixels.
Observations
Contributor: Marina Potapova - February 2012
Length Range: 9–13 µm
Width Range: 5.0–5.4 µm
Striae in 10 µm: 25–29
Description
Valves are elliptic. Raphe valve has a narrow linear axial area and transversely rectangular, or elliptic central area. The raphe is filiform and straight with slightly expanded, almost straight or very slightly deflected external distal ends. The internal proximal raphe ends are deflected to opposite sides. The internal distal raphe ends have small helictoglossae. The rapheless valve has a narrow linear axial area and an asymmetric central area. Striae are uniseriate. Areolae are isodiametric and number 35–40 in 10 μm. The central striae have 8–9 areolae in central striae, numbering 35-40 areolae in 10 μm. The external areolae openings are very small.
Original Description
Basionym: Psammothidium pennsylvanicum
Author: Potapova 2012
Length Range: 9–13 µm
Width Range: 5.0–5.4 µm
Striae in 10 µm: 25–29
Original Description
Original Images
Cite This Page:
Potapova, M. (2012). Psammothidium pennsylvanicum. In Diatoms of the United States. Retrieved May 24, 2013, from http://westerndiatoms.colorado.edu/taxa/species/psammothidium_pennsylvanicum
Species: Psammothidium pennsylvanicum
Contributor: Marina Potapova
Reviewer: Sarah Spaulding
Image Credit: Marina Potapova
- Valves small, elliptic
- Striae 25-29 in 10 μm
- Areolae 35-40 in 10 μm
- Rapheless valve with strongly asymmetric central area
Valves are elliptic. The raphe valve has a narrow linear axial area and transversely rectangular, or elliptic central area. The raphe is straight. The rapheless valve has a narrow linear axial area and an asymmetric central area. Areolae number 35–40 in 10 μm within each stria.
Compare
Psammothdium pennsylvanicum differs from P. semiapertum by a higher areola density (35-40 vs 25 in P. semiapertum) within each stria.
Psammothidium semiapertum
Citations
Potapova, M. (2012). New species and combinations in monoraphid diatoms (Family Achnanthidiaceae) from North America. Diatom Research 27(1): 29-42. doi:10.1080/0269249X.2011.644636
Links & ID's
Index Nominum Algarum (INA)
California Academy of Sciences (CAS)
North American Diatom Ecological Database (NADED)
NADED ID:
Autecology Discussion
Psammothidium pennsylvanicum has been found in 15 streams in north central Pennsylvania, including some affected by acid mine drainage. Conductivity in these streams ranged from 6 to 378 μS/cm, and pH from 4.0 to 7.0.