(Hilse) Cleve 1891 Category: Symmetrical biraphid
BASIONYM: Pinnularia ovalis Hilse in Rabenhorst 1861
REPORTED AS: Diploneis ovalis (Krammer and Lange-Bertalot 1986, p. 286, fig. 108: 14-16)
Contributor: Loren Bahls - October 2012
Length Range: 22-62 µm
Width Range: 12.5-23.0 µm
Striae in 10 µm: 11-14
Valves are elliptic to linear-elliptic with broadly rounded apices. The longitudinal canals are narrow, the width of one to three areolae, and follow along the margins of the axial and central areas. The axial area is occupied almost completely by a broad raphe sternum that encloses the raphe. The central area is large and orbicular, especially in larger specimens. Striae are uniseriate and radiate throughout. Areolae are large, blocky and number 15-20 in 10 µm.
Basionym: Pinnularia ovalis
Author: Hilse in Rabenhorst 1861
Length Range: µm
Striae in 10 µm:
Cleve, P.T. (1891). The Diatoms of Finland. Actas Societas Pro Fauna et Flora Fennica 8 (2): 1-68.
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.
Rabenhorst, L.G. (1861). Die Algen Europa’s Forsetzung der algen Sachsens, resp. Mittel-Europa’s. Decades 3-4, numbers 1021-1040. Dresden.
Diploneis ovalis is widely distributed in small headwater fens, ponds and streams in the mountains of the northwestern United States (Montana Diatom Database). Here it prefers cold, somewhat alkaline, oligotrophic waters with low to moderate conductivity (see table below). Common diatom associates of D. ovalis include Navicula aurora, Caloneis tenuis, Pinnularia borealis, Stauroneis kriegeri, Aulacoseira alpigena, and Fragilaria virescens.
Atlantic Pond, Glacier National Park, Montana: home of Diploneis ovalis.
Credit/Source: Loren Bahls
Abundance-weighted means of selected water quality variables measured concurrently with collection of samples containing Diploneis ovalis.
Credit/Source: Montana Diatom Database