Diploneis finnica
(Ehrenberg) Cleve 1891 Category: Symmetrical biraphid
BASIONYM: Cocconeis finnica Ehrenberg 1838
LM scalebar = 10 µm = 20 pixels.
Observations
Contributor: Loren Bahls - December 2011
Length Range: 52-107 µm
Width Range: 33-53 µm
Striae in 10 µm: 7-9
Description
Valves are broadly elliptical. The longitudinal canals are a distinctive lanceolate shape about 1/3 to 1/2 the width of the valve at center, which narrows towards the valve apices. The axial area is occupied almost completely by a broad raphe sternum that encloses the raphe. The central area is small and elliptical. Striae consist of double rows of areolae, one row may appear more prominent than the adjacent row. Striae are radiate throughout and extend onto the longitudinal canals. Areolae are distinct in LM and number 12-14 in 10 µm, but are more closely spaced over the longitudinal canals.
Original Description
Basionym: Cocconeis finnica
Author: Ehrenberg 1838
Length Range: µm
Striae in 10 µm:
Original Description
Original Images
Cite This Page:
Bahls, L. (2011). Diploneis finnica. In Diatoms of the United States. Retrieved May 25, 2013, from http://westerndiatoms.colorado.edu/taxa/species/diploneis_finnica
Species: Diploneis finnica
Contributor: Loren Bahls
Reviewer: Sarah Spaulding
Image Credit: Loren Bahls
- Valves large and broadly elliptical
- Longitudinal canals broad
- Striae biseriate
Diploneis finnica has large elliptical valves and biseriate striae. The longitudinal canals are wide and lanceolate and 1/3 to 1/2 the width of the valve at the center.
Compare
Diploneis finnica differs from D. smithii by wider, lanceolate longitudinal canals of D. finnica.
Diploneis smithii
(Brebisson ex W. Smith) Cleve
Citations
Cleve, P.T. (1891). The Diatoms of Finland. Actas Societas Pro Fauna et Flora Fennica 8 (2): 1-68.
Ehrenberg, C.G. (1838). Die Infusionsthierchen als vollkommene Organismen. Ein Blick in das tiefere organische Leben de Natur. erlag von Leopold Voss, Leipzig. pp. 1-xvii, 1-548, pls. 1-64.
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.
Patrick, R.M. and Reimer, C.W. (1966). The Diatoms of the United States exclusive of Alaska and Hawaii, V. 1. Monographs of the Academy of Natural Sciences of Philadelphia 13.
Links & ID's
Index Nominum Algarum (INA)
California Academy of Sciences (CAS)
North American Diatom Ecological Database (NADED)
NADED ID: 30002
Autecology Discussion
Diploneis finnica is a northern species. There are seven records of this species in the Montana Diatom Collection from lakes and streams in western Montana and northern Idaho. The pH of these waters ranges from 7.4 to 8.2 and specific conductance ranges from 39 to 90 µS/cm. Patrick and Reimer (1966) report Diploneis finnica from New England and the Pacific Northwest in "fresh water, particularly standing water, indifferent to small amounts of salt". As the specific epithet suggests, the type locality of this species is in Finland.
Images
Ross Creek, Lincoln County, northwest Montana: home of Diploneis finnica.
Credit/Source: Realty-Northwest.com