• Category
  • Length Range
    9-18 µm
  • Width Range
    2.7-3.5 µm
  • Striae in 10 µm



Valves are linear-elliptical with subrostrate or rounded ends. Axial area is narrowly linear. Central area is rectangular fascia. Striae are radiate in the middle, parallel or slightly convergent at apices, 35-40 in 10 mm. Raphe is filiform, straight or very slightly curved, with slightly expanded external proximal endings.


Original Description

Frustula delicata. Valvae lineari-lanceolatae marginibus subconvexis, apicibus obstuse rotundatis vix protractis, circiter 14 µ longae, 4 µ latae. Rhape directa filiformis. Area axialis angustissima linearis, area centralis fascian latam marginem fere attengentem formans. Structura delicatissima, striae transaicales subradiantes, circiter 40 in 10 µ.

  • Basionym
    Navicula fennica
  • Author
    Hust. 1962
  • Length Range
    14 µm
  • Width
    3 µm
  • Striae in 10µm

Original Images

Navicula Fennica Image007
Navicula Fennica Text002

Cite This Page

Potapova, M. (2010). Nupela fennica. In Diatoms of North America. Retrieved June 22, 2018, from https://diatoms.org/species/nupela_fennica


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