Valves linear-lanceolate and very narrow, tapering gently into rounded apices. Apices are slightly constricted. Raphe branches are greatly shortened and increase in length only slightly as the length of the valve increases. A long, low-profile median rib is present through most of the valve. At the raphe branches, two longitudinal ribs surround the raphe. At the distal raphe end, a porte-crayon structure of moderate size and shape is present. A thickened nodule is not evident at the internal central area. Striae are extremely fine and visible only under optimal objective lenses and illumination in the light microscope. Well-organized longitudinal striae are also present, but are not resolvable in the LM. External distal and proximal raphe ends are straight.
Graeff, C. (2012). Amphipleura pellucida. In Diatoms of North America. Retrieved November 23, 2024, from https://diatoms.org/species/amphipleura_pellucida
The 15 response plots show an environmental variable (x axis) against the relative abundance (y axis) of Amphipleura pellucida 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.