Diatoms of North AmericaDiatoms of North America

Neidiopsis hamiltonii

Bahls 2014

Neidiopsis Hamiltonii Guide
  • Category
    Symmetric Biraphid
  • Length Range
    19.5-43.6 µm
  • Width Range
    6.0-8.3 µm
  • Striae in 10 µm
    22-24
  • Reported As
    Neidiopsis levanderi? (Lange-Bertalot 2001, fig. 101: 16)
    Neidiopsis levanderi (Lange-Bertalot and Metzeltin 1996, fig. 29: 6)

Identification

Neidiopsis hamiltonii LM1 Neidiopsis hamiltonii LM2 Neidiopsis hamiltonii LM3 Neidiopsis hamiltonii LM4 Neidiopsis hamiltonii LM5 Neidiopsis hamiltonii LM6 Neidiopsis hamiltonii LM7
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Description

Valves are linear–lanceolate in large specimens, to elliptic–lanceolate in small specimens. Apices are broadly rounded and subcapitate in the largest specimens. The axial area is narrow and widens gradually toward the valve center where it merges with a small, rhomboidal central area. The raphe is filiform, with weakly expanded proximal ends. Proximal raphe ends are straight and relatively close to one another. The distal raphe fissures are curved toward the same side of the valve. Striae are weakly radiate at the valve center, becoming parallel toward the apices. Areola density within a stria is 20–26 in 10 μm. A prominent longitudinal line interrupts the striae on each side of the valve about midway between the raphe sternum and the valve margin, closer to the valve margin near the apices. Less prominent longitudinal lines are also evident.

Autecology

Neidiopsis hamiltonii has been recorded from two ponds in Colorado (3450 m a.s.l.) and from Hoskins Lake in northwest Montana (1036 m a.s.l.). The pH measured at these locations was 7.6 and specific conductance ranged from 40 to 67 μS cm−1. A single specimen of N. hamiltonii was also reported [as Neidiopsis levanderi?] from the ‘Rocky Mountains, Canada’ (Lange-Bertalot and Metzeltin 1996, Fig. 29: 6; Lange-Bertalot 2001, Fig. 101: 16).

Mexican Cut Ponds Nature Conservancy
Credit: Nature Conservancy
Mexican Cut Nature Preserve, Gunnison County, Colorado: home of Encyonema willeyorum

Original Description

Valves are linear–lanceolate in large specimens to elliptic–lanceolate in small specimens. Valve length 19.5–43.6μm, valve width 6.0–8.3μm. Apices are broadly rounded, rostrate to subcapitate in the largest specimens, subrostrate and weakly protracted in small specimens. The axial area is narrow and widens gradually towards the valve center where it merges with a rhomboidal central area. The raphe is filiform with weakly expanded proximal ends. Proximal raphe ends are straight and relatively close together. Distal raphe fissures are curved toward the same side of the valve. Striae are weakly radiate at the valve center, becoming parallel toward the apices. Stria density 22–24 in 10μm; areola density within a stria 20–26 in 10μm. A prominent longitudinal line interrupts the striae on each side of the valve about midway between the raphe sternum and the valve margin, coming closer to the valve margin near the apices. Less prominent longitudinal lines are also evident. Plastids were not observed.

  • Author
    Bahls 2014
  • Length Range
    19.5-43.6 µm
  • Width
    6.0-8.3 µm
  • Striae in 10µm
    22-24

Original Images

Neidiopsis Bahls Figures 1 17
Neidiopsis Bahls Figures 18 23
Neidiopsis Bahls Figures 24 29

Cite This Page

Bahls, L. (2015). Neidiopsis hamiltonii. In Diatoms of North America. Retrieved April 26, 2024, from https://diatoms.org/species/neidiopsis_hamiltonii

Responses

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