A. Schmidt 1876 Category: Symmetrical biraphid
BASIONYM: Navicula ludloviana A. Schmidt 1876
Contributor: Loren Bahls - November 2011
Length Range: 103-159 µm
Width Range: 30-37 µm
Striae in 10 µm: 6 in the center of the valve, - 8 at the ends
Valves are rhombic-lanceolate with non-protracted, acutely rounded ends. The axial area is broad, widening into an orbicular central area. The raphe is lateral and distinctly bowed and concave to the primary side. External proximal raphe ends are large and bulbous and deflected slightly to the secondary side. Striae are wide and lineate, radiate throughout, and alternately longer and shorter about the central area. Areolae are fine and number 26-30 in 10 µm. Voigt discontinuities are evident on the secondary side of larger specimens.
Basionym: Navicula ludloviana
Author: A. Schmidt 1876
Length Range: µm
Striae in 10 µm:
Cleve-Euler, A. (1953). Die Diatomeen von Schweden und Finnland. Teil III. Monoraphideae, Biraphideae 1. Authorized Reprint 1968, Bibliotheca Phycologica, Band 5, J. Cramer, Lehre.
Lange-Bertalot, H. (2001). Navicula sensu stricto, 10 genera separated from Navicula sensu lato, Frustulia. Diatoms of Europe 2: 1-526.
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.
Schmidt, A. (-). (1874-1959). Atlas der Diatomaceen-Kunde, von Adolf Schmidt, continued by Martin Schmidt, Friedrich Fricke, Heinrich Heiden, Otto Muller, Friedrich Hustedt. Reprint 1984, Koeltz Scientific Books, Konigstein, 480 plates.
Navicula ludloviana was described from material collected near Port Ludlow in Washington State on the east side of the Olympic Peninsula in the Puget Sound area. Patrick & Reimer (1966) report this taxon from Washington, Oregon, and California. The Montana Diatom Collection has one sample containing Navicula ludloviana from Upper Clearwater Creek in the headwaters of the North Umpqua River, Cascade Mountains, southwestern Oregon. On the sampling date this site had a pH of 6.7 and a specific conductance of 38 µS/cm. There is a questionable report of this taxon from Finnish Lapland by Cleve-Euler (1953).
North Umpqua River, Oregon: home of Navicula ludloviana.
Credit/Source: Kurt Carpenter, USGS