Cymbella maggiana

Krammer 2002      Category: Asymmetrical biraphid

Cymbella lanceolata


Cymbella mexicana

LM scalebar = 10 µm = 40 pixels.


Contributor: Loren Bahls - May 2016
Length Range: 29-78 µm
Width Range: 10.5-14.3 µm
Striae in 10 µm: 8-12 at the valve center, up to 14 near the apices


Valves are lanceolate and dorsiventral, with bluntly rounded apices. The dorsal margin is moderately arched. The ventral margin is nearly flat, with a slightly gibbous center. The axial area is narrow, barely wider than the raphe, and located just ventral to the valve mid line. The central area is small and rhombic in shape. The raphe is distinctly lateral, becoming reverse lateral at the proximal ends. Proximal raphe ends are deflected ventrally and terminate in small pores. Distal raphe fissures are filiform and deflected dorsally at about 45 degrees. Striae are radiate throughout, and more strongly radiate near the apices. Areolae are distinct in LM and number 18-24 in 10 µm. Isolated stigmata number 2-5 at the proximal ends of the median ventral striae.

Original Description

Author: Krammer 2002
Length Range: 43-63 µm
Width Range: 10.5-12.7 µm
Striae in 10 µm: 10-12 at the valve center, up to 15 near the apices

Original Description

Original Images

Cite This Page:
Bahls, L. (2016). Cymbella maggiana. In Diatoms of the United States. Retrieved April 22, 2018, from

Species: Cymbella maggiana

Contributor: Loren Bahls

Reviewer: Teofil Nakov


Krammer, K. (2002). The genus Cymbella. Diatoms of Europe. Diatoms of the European Inland Waters and Comparable Habitats 3: 1-584.

Links & ID's

Index Nominum Algarum (INA)

Original INA

California Academy of Sciences (CAS)

Cymbella maggiana CAS

North American Diatom Ecological Database (NADED)


Autecology Discussion

Cymbella maggiana has been collected from two streams in adjacent watersheds of Glacier National Park, Montana. These streams–Logging Creek and Quartz Creek–are on the west side of the Park in the Flathead River drainage. At the time of collection, pH and specific conductance measured 7.74 and 50 µS/cm, respectively, in one of these streams (Logging Creek). The type locality of this species is the River Maggia in Ticino, Switzerland. Krammer (2002) reports that this species is found in several oligotrophic alpine rivers in this region of the Alps.