Diatoms of North AmericaDiatoms of North America

Navicula recens

Lange-Bert. in Krammer and Lange-Bert. 1985

N Recens Guide
  • Category
    Symmetric Biraphid
  • Length Range
    17-42 µm
  • Width Range
    5.8-8.2 µm
  • Striae in 10 µm
    11–13
  • Reported As
    Navicula tripunctata var. schizonemoides (early ANSP (1970-80's) usage)

Identification

46649 Lm2 46649 Lm5 46649 Lm4 46649 Lm3 46649 Lm6 46649 Lm1 46649 Lm7
View image metadata
46649 Sem3 46649 Sem2 46649 Sem1

Description

Valves are lanceolate with wedge-shaped ends. The raphe is straight and filiform. The axial area is narrow and linear. The central area is round or transversely rectangular. Striae are radiate, becoming convergent at the valve apices. Striae number 11-13 in 10 µm. Areolae number approximately 30-33 in 10 µm. Striae are bent in the middle of the valve and short striae often alternate with longer ones around the central area.

Autecology

This taxon prefers brackish water or fresh water of high mineral content, eutraphentic.

Original Description

A typo differt valvis modice magis elliptico-lanceolatis contra lineari-lanceolatas, 20-40 µm longis, 7-9 µm latis. Area centralis paulo minus lateraliter elongata, poris centralibus se ipsis magis appropinquatis.

  • Basionym
    Navicula cari var. recens
  • Author
    Lange-Bert. 1980
  • Length Range
    20-40 µm
  • Width
    7–9 µm

Original Images

Narecens Orig Illus
Narecens Orig Descr
Original text and images reproduced with permission by Elsevier.

Cite This Page

Potapova, M. (2009). Navicula recens. In Diatoms of North America. Retrieved November 21, 2024, from https://diatoms.org/species/navicula_recens

Responses

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