(Grunow) Krammer 2003 Category: Asymmetrical biraphid
BASIONYM: Cymbella lapponica Grunow in Cleve 1894
REPORTED AS: Cymbella lapponica (Krammer and Lange-Bertalot 1986, p. 330, pl. 137, figs. 12-17)
Contributor: Loren Bahls - December 2012
Length Range: 27-47 µm
Width Range: 7.2-9.6 µm
Striae in 10 µm: 16-19 at the valve center, 20-22 near the apices
Valves are weakly dorsiventral, rhombic-lanceolate, tapering gradually from the middle to narrow, subapiculate apices. The axial area is broad and follows the valve midline. The central area is asymmetric, with the dorsal side more developed. The raphe is weakly lateral, narrowing toward the proximal and distal ends. Proximal raphe ends are deflected slightly toward the ventral side. Terminal raphe fissures are comma shaped and deflected dorsally. Striae are radiate throughout. Areolae number 28-30 in 10 µm.
Basionym: Cymbella lapponica
Author: Grunow in Cleve 1894
Length Range: µm
Striae in 10 µm:
Cleve, P.T. (1894). Synopsis of the Naviculoid Diatoms, Part I. Kongliga Svenska-Vetenskaps Akademiens Handlingar 26(2):1-194, 5 pls.
Krammer, K. (2003). Cymbopleura, Delicata, Navicymbula, Gomphocymbellopsis, Afrocymbella. Diatoms of Europe. Diatoms of the European Inland Waters and Comparable Habitats 4: 1-530.
Krammer, K. and Lange-Bertalot, H. (1986). Bacillariophyceae. 1. Teil: Naviculaceae. In: Ettl, H., J. Gerloff, H. Heynig and D. Mollenhauer (eds.) Susswasserflora von Mitteleuropa, Band 2/1. Gustav Fisher Verlag, Jena. 876 pp.
Cymbopleura lapponica has been collected in small numbers from six lakes, ponds, swamps and streams in the northern Rocky Mountains of Montana and Alberta. Here pH ranged from 7.78 to 8.04 and specific conductance varied from 129-183 µS/cm. Krammer (2003) reports this species from the subarctic (Spitsbergen), far northern Scandinavia, and the Alps. The type locality is in Swedish Lapland.
Bullhead Lake, Glacier National Park, Montana: home of Cymbopleura lapponica.
Credit/Source: Loren Bahls