Navicula caroliniae
Bahls 2012 Category: Symmetrical biraphid
BASIONYM: Navicula caroliniae Bahls 2012
LM scalebar = 10 µm = 40 pixels.
Observations
Contributor: Loren Bahls - March 2012
Length Range: 23-41 µm
Width Range: 7.9-9.9 µm
Striae in 10 µm: 11-14
Description
Valves are broadly lanceolate with protracted and obtusely rounded to subcapitate apices. Raphe branches are weakly lateral. Proximal raphe ends are straight or deflected slightly to the secondary side. Distal raphe fissures are hooked to the secondary side. The axial area is narrow and linear, widening slightly toward the central area. The central area is large, rounded, and asymmetric, always smaller on the secondary side of the valve. Striae are evenly spaced throughout, radiate in the center and becoming parallel to slightly convergent at the apices. Areolae number 24–28 in 10 μm and are visible in LM.
Original Description
Basionym: Navicula caroliniae
Author: Bahls 2012
Length Range: 23-40 µm
Width Range: 7.9-9.9 µm
Striae in 10 µm: 11-14
Original Description
Valves broadly lanceolate with protracted, obtusely rounded to subcapitate ends, 23–40 μm long, 7.9–9.9 μm wide. Raphe weakly lateral, proximal raphe endings straight or deflected slightly to the secondary side, distal fissures hooked to the secondary side. Axial area narrow, linear, widening slightly toward the central area. Central area large, rounded, and asymmetric. Striae radiate, becoming parallel to slightly convergent at the ends, 11–14 in 10 μm, lineolae 24 – 28 in 10 μm, visible in LM. For measurements, n = 30 valves. SEM (Figs 42 – 44): External raphe fissures weakly lateral, proximal endings defl ected slightly to the secondary side. Distal raphe endings hooked, the hooks opening toward the secondary side (the side with the Voigt faults). Other external features unremarkable for Navicula species.
Original Images
Cite This Page:
Bahls, L. (2012). Navicula caroliniae. In Diatoms of the United States. Retrieved May 18, 2013, from http://westerndiatoms.colorado.edu/taxa/species/navicula_caroliniae
Species: Navicula caroliniae
Contributor: Loren Bahls
Reviewer: Mark Edlund
Image Credit: Loren Bahls
- Valves broadly lanceolate
- Apices obtusely rounded to subcapitate
- Striae evenly spaced
- Areolae 24-28 in 10 μm
Navicula caroliniae has broadly lanceolate valves 23-41 μm long with obtusely rounded to subcapitate apices. Striae number 11-14 in 10 μm and are evenly spaced throughout the valve. Areolae number 24-28 in 10 μm.
Compare
Navicula elsoniana has narrower ends and grows in brackish water. Navicula hanseatica has more widely spaced striae and coarser areolae. Navicula rhynchocephala has longer valves and striae that are more widely spaced around the central area. Navicula rhynchotella is larger, has coarser areolae and grows in brackish waters.
Navicula rhynchocephala
Navicula rhynchotella
Navicula elsoniana
Patrick & Freese 1960
Navicula hanseatica
Lange-Bertalot & Stachura 1998
Citations
Bahls, L.L. (2012). Seven new species in Navicula sensu stricto from the Northern Great Plains and Northern Rocky Mountains. Nova Hedwigia, Beiheft 141: 19–38.
Links & ID's
Index Nominum Algarum (INA)
California Academy of Sciences (CAS)
North American Diatom Ecological Database (NADED)
NADED ID:
Autecology Discussion
Navicula caroliniae has been collected from 17 lakes, ponds, and slow-moving streams in the Canadian Rockies (“Crown of the Continent”) Ecoregion of Montana and Alberta, where it is present in low numbers. It prefers waters with circumneutral to somewhat alkaline pH (range 6.5-8.6) and low to moderate levels of electrolytes (range 92-332 μS/cm).
Images
Bowman Lake, Glacier National Park, Montana: type locality of Navicula caroliniae.
Credit/Source: Loren Bahls