Rossithidium anastasiae
(Kaczmarska) Potapova 2012 Category: Monoraphid
BASIONYM: Achnanthes anastasiae Kaczmarska 1985
REPORTED AS: Achnanthes lineariformis (Lange-Bertalot 1993) | Achnanthes linearioides (Lange-Bertalot in Lange-Bertalot and Moser 1994) | Achnanthes linearis (Germain 1981)
Observations
Contributor: Marina Potapova - January 2012
Length Range: 12-26 µm
Width Range: 3.7-4.5 µm
Striae in 10 µm: 24-29
Description
Valves are linear or linear-elliptic with rounded ends. The raphe valve has a linear axial area that gradually widens into a small or almost indistinct central area. The raphe is straight, filiform, and lacks terminal fissures. Internally, the central raphe endings are curved to opposite sides. The rapheless valve has a narrow, linear axial area and no distinct central area. Striae are uniseriate and slightly radiate. Each stria in the middle part of the valve contains 5-6 areolae on valve face. The valve mantle bears one row of areolae.
Original Description
Basionym: Achnanthes anastasiae
Author: Kaczmarska 1985
Length Range: 17-25 µm
Width Range: 4-5 µm
Striae in 10 µm: 24–26 on the raphe valve, 22–25 on the rapheless valve
Original Description
Original Images
Cite This Page:
Potapova, M. (2012). Rossithidium anastasiae. In Diatoms of the United States. Retrieved May 18, 2013, from http://westerndiatoms.colorado.edu/taxa/species/rossithidium_anastasiae
Species: Rossithidium anastasiae
Contributor: Marina Potapova
Reviewer: Loren Bahls
Image Credit: Marina Potapova
- Valve linear to linear-elliptic
- Raphe straight
- Striae unseriate
- Raphe valve with a small or indisctinct central area
- Rapheless valve with a narrow linear axial area
Valves are linear or linear-elliptic with rounded ends. The raphe valve has a linear axial area that gradually widens into a small or almost indistinct central area. The rapheless valve has a narrow, linear axial area and no distinct central area. Striae are uniseriate and slightly radiate.
Compare
Rossithidium anastasiae differs from R. pusillum by having larger valves, higher stria density, and wider axial area on the raphe valve. Rossithidium petersenii has much larger central area on the raphe valve and a wider, rhomboid axial area on the rapheless valve. Rossithidium anastasiae can be distinguished from various species of Achnanthidium by the absence of terminal raphe fissures.
Rossithidium petersenii
Rossithidium pusillum
Citations
Hofmann, G., Werum, M. and Lange-Bertalot, H. (2011). Diatomeen im Süßwasser-Benthos von Mitteleuropa. Koeltz Scientific Books, Königstein, 908 pp.
Kaczmarska, I. (1985). The diatom flora of Miocene lacustrine diatomites from the Harper Basin, Oregon, U.S.A. Acta Palaeobotanica 25(1-2):33-100.
Krammer, K. and Lange-Bertalot, H. (2004). Bacillariophyceae 4. Teil: Achnanthaceae, Kritische Erganzungen zu Navicula (Lineolatae), Gomphonema Gesamtliteraturverzeichnis Teil 1-4 [second revised edition]. In: H. Ettl et al., Suesswasserflora von Mitteleuropa. Spektrum Akademischer Verlad Heidelberg, 468 pp.
Mölder, K. and Tynni, R. (1972). Uber Finnlands rezente und subfossile Diatomeen VI. Bulletin of the Geological Society of Finland 44: 141–159.
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
Rossithidium anastasiae is a widely distributed diatom, often found in colder waters in Europe (Mölder & Tynni 1972, Krammer & Lange-Bertalot 2004) and in North America. Considering that most records of R. linearis are in fact R. anastasiae, data in the ANSP databases and catalogues show that this species is often found in low-conductivity lakes and sometimes streams of the northeastern USA, and, occasionally, in the Rocky Mountains. Hofmann et al. (2011) stated that this diatom is mostly found in oligo- to mesotrophic waters of low conductivity.