Identification

Description

Valves are elliptical. The axial area is linear; the central area is small, elliptical. The raphe is filiform with expanded external proximal ends. The terminal raphe fissures are small. The striae are strongly radiate and coarsely punctate. Long and short striae alternate in the central area. The stria density increases towards the apices. Areolae are elliptical and number 10-14 in 10 μm.

Autecology

Original Description

Navicula Scutelloides, W.Sm. Valve nearly orbicular ; striæ moniliform, 18 in •001”. Length of F. •007”. Breadth of •0006”. v.v. W. Sm. In Greg. Mic. Journ. vol. iv. P. 4. pl. i. 15. Fresh water. Ormesby, Norfolk, Sept. 1853, Mr. Bridgman. Rosthern Mere, Cheshire, Sept. 1855, Dr. Arnott. Cantyre Peat, &c.

  • Basionym
    Navicula scutelloides
  • Author
    W.Sm. 1856

Original Images

Navicula scutelloides orig illus
Navicula scutelloides orig descr

Cite This Page

Potapova, M. (2011). Cavinula scutelloides. In Diatoms of North America. Retrieved July 22, 2018, from https://diatoms.org/species/cavinula_scutelloides

Responses

The 15 response plots show an environmental variable (x axis) against the relative abundance (y axis) of Cavinula scutelloides 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.