Diatoms of North AmericaDiatoms of North America

Craticula accomoda

(Hust.) D.G.Mann in Round, R.M.Crawford and D.G.Mann 1990

Craticula Accomoda Guide
  • Category
    Symmetric Biraphid
  • Length Range
    19.0-20.3 µm
  • Width Range
    4.8-6.4 µm
  • Striae in 10 µm
    20-26

Identification

Craticula accomoda LM6 Craticula accomoda LM4 Craticula accomoda LM3 Craticula accomoda LM7 Craticula accomoda LM2 Craticula accomoda LM5 Craticula accomoda LM1
View image metadata
Craticula accomoda SEM1

Description

Valves are linear-lanceolate, with rostrate to subcapitate, rounded apices. The axial area is narrow and the central area only slightly expanded. Striae are weakly radiate near the valve center, then parallel, becoming convergent near the apices. The raphe is filiform. The distal raphe ends are unidirectionally deflected. Areolae are not visible in LM.

Autecology

Usgs Biodata C Accomoda Map
Credit: USGS BioData
Distribution of Craticula accomoda in continental U.S. rivers in the National Water Quality Assessment program. Retrieved 03 June 2015.
Usgs Biodata C Accomoda Map Alaska
Credit: USGS BioData
Distribution of Craticula accomoda in Alaskan rivers in the National Water Quality Assessment program. Retrieved 03 June 2015.

Original Description

Navicula accomoda nov. spec. Schalen elliptisch-lanzettlich mit kurz geschnäbelten Enden, um 22 µ lang, etwa 7,5 µ breit. Raphe gerade, fadenförmig, mit etwas entfernt gestellten Zentralporen und kleinen, kaum unterscheidbaren Polspalten. Axialarea schmal linear, um den Zentralknoten nur sehr wenig erweitert. Transapikalstreifen durchweg senkrecht zur Mittellinie, in der Mitte, etwa 25 in 10 µ, gegen die Enden allmählich enger werdend, bis etwa 32 in 10 µ, sehr zart punktiert. Taf. XXXIX, Fig. 17, 18.

Charemsee, sehr selten.

Die Art hat gewisse Ähnlichkeiten mit Navicula halophila (GRUN.) CLEVE und N. simplex KRASSKE, unterscheidet sich aber von beiden Formen durch die im mittleren Teil der Schalen entfernter stehenden Streifen, von N. simplex auch durch die Richtung besonders der Polstreifen.

Während des Druckes dieser Arbeit wurde die Art von weiteren Standorten bebannt: MAX MÖLLER (Odense) fand sie auf Fünen, MESSIKOMMER stellte sie in der Schweiz fest (massenhaft, fast rein, in einer Probe aus dem Hemmentaler Bach, Kanton Schaffhausen) und mein Schuler stud. ret. nat. MARTIN SCHEELE fand sie in der Fulda. Das Material von den genannten Standorten hat mir zur Nachprüfung vorgelegen.

  • Basionym
    Navicula accomoda
  • Author
    Hust. 1950
  • Length Range
    22 µm
  • Width
    7.5 µm
  • Striae in 10µm
    25

Original Images

Navicula accomoda orig illus
Craticula accomoda orig descr

Cite This Page

Bishop, I., Burge, D. (2015). Craticula accomoda. In Diatoms of North America. Retrieved April 20, 2024, from https://diatoms.org/species/craticula_accomoda

Responses

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