The dorsal margin is strongly convex and the ventral margin is straight, to slightly convex. Dorsal striae are parallel in the center of the valve, becoming radiate toward the apices. The ventral striae are parallel in the center, becoming convergent near the apices. Striae have approximately 30 areolae in 10 µm. The axial area is straight and narrow, becoming slightly wider in the central valve. The proximal raphe ends are slightly curved toward the the dorsal margin. The distal raphe ends are strongly deflected toward the ventral margin.
Lowe, R. (2015). Encyonema minutum. In Diatoms of North America. Retrieved September 07, 2024, from https://diatoms.org/species/encyonema_minutum
The 15 response plots show an environmental variable (x axis) against the relative abundance (y axis) of Encyonema minutum 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.