• Category
  • Length Range
    12-28 µm
  • Width Range
    4.9-8.5 µm
  • Striae in 10 µm
    8-11

Identification

Description

Valves are elliptical-lanceolate with capitate to subcapitate apices. The axial area is narrow and linear. The central area is small, round or elliptical. The raphe is straight, filiform, with slightly expanded external proximal ends. The distal raphe ends are deflected to the secondary valve side. The striae are biseriate, radiate in the valve center and convergent at the apices. The areolae are elongated and generally oriented in the apical axis. Internally the striae open into shallow alveoli. A hyaline area and one or two apical rows of areolae are present at each end of the valve.

Autecology

Original Description

N. striata, testula brevi ovato-lanceolata, utroque fine constricta obtuse, in centesima lineae parte 10 strias offerens.

  • Basionym
    Navicula capitata
  • Author
    Ehrenb. 1838

Original Images

Nacapit  Or Ill 1
Nacapit  Or Descr1

EMAP Assessment

EMAP Distribution

Hippondonta Capitata 40 Copy
Map 40

Response Plots

Hippodonta Capitata Copy

Cite This Page

Potapova, M. (2011). Hippodonta capitata. In Diatoms of North America. Retrieved August 15, 2018, from https://diatoms.org/species/hippodonta_capitata

Responses

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