Diatoms of North AmericaDiatoms of North America

Aulacoseira nygaardii

(Camburn) Camburn and Charles 2000

Aulacoseira Nygaardii Guide
  • Category
    Centric
  • Diameter
    4-11 µm
  • Width Range
    4-19 µm
  • Striae in 10 µm
    22-31

Identification

Aulacoseira nygaardii LM1 Aulacoseira nygaardii LM2 Aulacoseira nygaardii LM4 Aulacoseira nygaardii LM5 Aulacoseira nygaardii LM3 Aulacoseira nygaardii LM6 Aulacoseira nygaardii LM7
View image metadata Type

Description

Frustules are cylindrical and form short chains. The ratio of the mantle height to valve diameter is close to 1. The mantle has straight sides, but the mantle/valve face junction is rounded. The valve face appears slightly convex in LM, but flat in SEM. Rows of pervalvar areolae are straight, parallel to the pervalvar axis, 22-31 in 10 µm, with 30-42 areolae in 10 μm. The height of the collum is approximately1/2-1/3 of the mantle height. The valve face is plain, but with short radial striae at the periphery. The spines are anchor-shaped, narrow, and originate from every second or third costa. The ringleiste is shallow and bell-shaped in cross-section.

Autecology

This taxon appears to be limited to northeastern and Upper Midwest North America, and rather rarely reported from modern samples. Verified reports are from Michigan, Wisconsin, and Minnesota (Camburn and Kingston 1986), the northeastern US (Camburn and Kingston 1986, Camburn and Charles 2000), Quebec, Labrador (Fallu et al. 2000), and Cape Cod (Siver et al. 2005, Siver and Hamilton 2005). In the original description (Camburn and Kingston 1986), populations are also reported from Florida and Georgia; however, Siver and Hamilton (2005) report a similar taxon from that locality that was not of the type based on SEM analysis and recommended an SEM analysis of populations reported from southeastern states. Siver and Hamilton (2005) noted that the specimens presented in Florin (1981) in figs 47-49 may represent a population of A. nygaardii, which would expand the documented range to include northern Europe.

In the Great Lakes National Parks (Edlund et al. 2011, 2012, 2013), it is rare (1-2% relative abundance) in sediment core material from lakes in Voyageurs (Ryan and Elk lakes) and at St. Croix National Scenic Riverway (Lake St. Croix) (Edlund et al. 2009).

This taxon is reported to prefer weakly acidic, nutrient-poor habitats (Siver et al. 2005, Siver and Hamilton 2005) and appears to be sensitive to anthropogenic disturbance (Manoylov et al. 2009).

Several research groups consider this taxon an indicator organism and published regional environmental optima and tolerances including:

Camburn and Charles (2000): Abundance Weighted Mean (AWM) pH – 6.05 +/- 0.85, AWM Acid Neutralizing Capacity (ANC) – 38 +/- 63 µeq/L, AWM total Al – 142 +/- 157 µg/L, AWM Dissolved Organic Carbon (DOC) – 301 +/- 149 µmol/L, AWM Total Phosphorus (TP) – 5.95 +/- 4.00 µg/L for populations from low alkalinity lakes in Northeastern US.

Fallu et al. (2000): DOC 14.11 +/- 1.26 mg/L for populations from Quebec. Color – 17 +/- 1.4 Pt units, Alkalinity – 31 +/- 1.8 µeq/L for populations from Labrador.

Siver and Hamilton (2005): report the populations they investigated from Cape Cod to occur in waters with pH ranging from 4.9-6.9.

Original Description

Frustules rectangular in girdle view, valves slightly rounded at the mantle. Valve (5.0) 6.9-11.0 μm in diameter. Pervalvar axis variable in length, (4.0) 7.0-17.0 (19.0) μm. Valve mantle contains striae which are parallel to the pervalvar axis, striae 20-22 in 10 μm. Striae are finely punctate, puncta 25-30 in 10 μm. Sulcus well developed. Periphery of valve face ornamented with a narrow (<1.0 μm) band of radiate striae. Striae ca. 30 in 10 μm. The remaining valve face is unornamented. A row of spines occurs around the circumference of the valve face, a spine is located every 2-3 striae. Spines ca. 1.0-1.5 μm in length

  • Basionym
    Melosira nygaardii
  • Author
    Camburn in Camburn and Kingston 1986
  • Length Range
    5-11 µm
  • Width
    4-19 µm
  • Striae in 10µm
    20-22

Original Images

Orig Ill Aunyg
Orig Descr Aunyg 2
Original text and images reproduced with permission by Academy of Natural Sciences of Philadelphia.

Citations & Links

Citations

Links

  • Index Nominum Algarum
    Original
  • North American Diatom Ecological Database
    NADED ID: 10039

Updates

Nov 08, 2024 - Addition of Autecology

From 2010 until 2024 the autecological information on this taxon page was limited. As of this update, information on ecology, biogeography, and environmental optima have been added. - Lane Allen & Mark Edlund

Cite This Page

Potapova, M., English, J., Allen, L., Edlund, M. (2010). Aulacoseira nygaardii. In Diatoms of North America. Retrieved November 21, 2024, from https://diatoms.org/species/aulacoseira_nygaardii

Responses

The 15 response plots show an environmental variable (x axis) against the relative abundance (y axis) of Aulacoseira nygaardii from all the stream reaches where it was present. Note that the relative abundance scale is the same on each plot. Explanation of each environmental variable and units are as follows:

ELEVATION = stream reach elevation (meters)
STRAHLER = distribution plot of the Strahler Stream Order
SLOPE = stream reach gradient (degrees)
W1_HALL = an index that is a measure of streamside (riparian) human activity that ranges from 0 - 10, with a value of 0 indicating of minimal disturbance to a value of 10 indicating severe disturbance.
PHSTVL = pH measured in a sealed syringe sample (pH units)
log_COND = log concentration of specific conductivity (µS/cm)
log_PTL = log concentration of total phosphorus (µg/L)
log_NO3 = log concentration of nitrate (µeq/L)
log_DOC = log concentration of dissolved organic carbon (mg/L)
log_SIO2 = log concentration of silicon (mg/L)
log_NA = log concentration of sodium (µeq/L)
log_HCO3 = log concentration of the bicarbonate ion (µeq/L)
EMBED = percent of the stream substrate that is embedded by sand and fine sediment
log_TURBIDITY = log of turbidity, a measure of cloudiness of water, in nephelometric turbidity units (NTU).
DISTOT = an index of total human disturbance in the watershed that ranges from 1 - 100, with a value of 0 indicating of minimal disturbance to a value of 100 indicating severe disturbance.