Identification

Description

Valves are strongly dorsi-ventral. The dorsal margin is broadly arched, while the ventral margin is only slightly expanded. Valves 50-84 μm long; 22-27 μm wide. The valve apices are rounded. The axial area is relatively broad in the central part, narrowing at the valve ends. The raphe branches are lateral and have a slight arch towards the ventral margin. Each raphe branch is positioned nearly centrally within the axial area. Proximal raphe ends are slightly expanded and dorsally deflected. Distal raphe ends curve slightly to the dorsal margin, but are deflected ventrally near the valve apices. The dorsal striae are divergent. Externally, the rows of dorsal areolae closest to the central area are oval, and become lineolate. Dorsally, central striae 6-8 in 10 μm and distal striae 4-5 in 5 μm. Ventral, central striae 7-8 in 10 μm, distal striae 5 in 5 μm. Areolae density within a central, dorsal stria is 6-7 in 5 μm.

Autecology

Original Description

Cite This Page

Spaulding, S. (2010). Encyonema latum. In Diatoms of North America. Retrieved June 23, 2018, from https://diatoms.org/species/encyonema_latum

Responses

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