Diatoms of North AmericaDiatoms of North America

Pinnularia perinterrupta

Krammer 2000

Pinnularia perinterrupta guide
  • Category
    Symmetric Biraphid
  • Length Range
    31.4-37.5 µm
  • Width Range
    6.5-7 µm
  • Striae in 10 µm
    12-13
  • Synonyms
    Pinnularia subrostrata A. Cleve sensu Krammer & Lange-Bertalot
    Pinnularia subrostrata A. Cleve sensu Krammer

Identification

Pinnularia perinterrupta LM3 Pinnularia perinterrupta LM7 Pinnularia perinterrupta LM1 Pinnularia perinterrupta LM5 Pinnularia perinterrupta LM2 Pinnularia perinterrupta LM6 Pinnularia perinterrupta LM4
View image metadata

Description

Valves are linear. Ends are broadly capitate and rounded. The axial area is narrow. The raphe is filiform. The proximal raphe ends curve slightly to the primary valve side. The distal raphe terminates in question-marked shaped fissures. The central area widens into a moderately broad, bow-tie shaped fascia. Striae are strongly radiate in the center, becoming strongly convergent near the apices.

Autecology

Specimens shown on this page are from Alaskan tundra ponds, collected by L.R. Freese (Patrick and Freese, 1961).

Krammer (2000) reported Pinnularia perinterrupta as "not rare in nordic oligotrophic waters with low electrolyte content".

Original Description

Valves linear, sides weakly convex to triundulate, ends broadly capitate and flatly rounded, length 28-56 um, breadth 6.8-8 um. Raphe branches commonly straight, central pores drop-like, curved a little to one side, terminal fissures relatively large, ?-shaped. Axial area very narrow, linear, central area a moderately broad fascia. Striae 9-11/10 um, extremely divergent with a sudden change in direction half-way to the ends, strongly radiate towards the valve centre, strongly convergent towards the ends.

Distribution: Not rare in nordic oligotrophic waters with low electrolyte content.

In the past this taxon frequently was confused with Pinnularia divergentissima var. sub-rostrata A. Cleve (Fig. 60: 6, see above under 38.3), which is of much smaller size.

  • Author
    Krammer 2000
  • Length Range
    28-56 µm
  • Width
    6.8-8 µm
  • Striae in 10µm
    9-11

Original Images

Pinnularia perinterrupta orig illus
Pinnularia perinterrupta orig desc

Citations & Links

Citations

Links

  • Index Nominum Algarum
  • DiatomBase
    Link
  • The Academy of Natural Sciences, Drexel University
    Link

Cite This Page

Leppik, S., Potapova, M. (2025). Pinnularia perinterrupta. In Diatoms of North America. Retrieved May 17, 2025, from https://diatoms.org/species/62606/pinnularia-perinterrupta

Responses

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