• Category
  • Length Range
    15-19 µm
  • Width Range
    4.3-5.5 µm
  • Striae in 10 µm
    19-24
  • Synonyms
    Navicula ruttneri var. capitata Hust. 1937 (replaced synonym)

Identification

Description

Valves are lanceolate to elliptic. The apices are narrowly rounded and slightly capitate. The raphe is straight, with slightly inflated proximal ends and terminal fissures deflected to the same side. Striae are uniseriate, radiate throughout and slightly curved. The central area is variable; some specimens have a central area that extends to the valve margin, others have a more bowtie-shaped central area, bordered by shortened striae of alternating length. The axial area is narrow and straight, expanding slightly at the middle of the valve.

The name, Sellaphora javanica, is a replacement name for Navicula ruttneri var. capitata. Sellaphora javanica is very similar to S. japonica and the two taxa have frequently been confused with one another.

Autecology

This taxon was found in rivers of the southeast (Bishop et al. 2017), with the images on this page from North Carolina and Virginia.

Original Description

Navicula Ruttneri nov. spec. Schalen elliptisch-lanzettlich mit schwach vorgezogenen, stumpf gerundeten Enden, 8-25 μ lang, 3-5 μ breit, an den Polen mit kurzen Pseudosepten, die bei den kleinsten Individuen zuweilen stark reduziert sind. Raphe gerade, Axialarea eng, Zentralarea quer verbreitert, zuweilen bis fast an den Schalenrand reichend. Transapikalstreifen durchweg radial, die mittleren verkürzt, etwa 22 in 10 μ, von der Mitte gegen die Enden etwas enger werdend. Taf. XVII. Fig. 18-23.

Herrn Prof. Dr. Fr. Ruttner gewidmet.

Von der Art lassen sich folgende Grenzvariationen unterscheiden:

var. capitata nov. var. Kurze Formen mit breiten, kopfig abgeschnurten Enden. Taf. XVII. Fig. 24-26.

  • Basionym
    Navicula ruttneri var. capitata
  • Author
    Hust. 1937
  • Length Range
    8-25 µm
  • Width
    3-5 µm
  • Striae in 10µm
    22

Original Images

N Ruttneri Var Capitata Orig Desc Plate
Hustedt neotypes
N Ruttneri Var Capitata Orig Desc Text

Cite This Page

Bishop, I., Greenwood, J. (2021). Sellaphora javanica. In Diatoms of North America. Retrieved September 26, 2022, from https://diatoms.org/species/sellaphora_javanica

Responses

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