• Category
  • Length Range
    56-105 µm
  • Width Range
    6.2-8.1 µm
  • Striae in 10 µm



Valves are elongate and linear to lanceolate. A slight constriction is often present at the center of the valve. The valves taper to bluntly rounded apices. Fibulae are thick at the valve margin and extend across the valve, either halfway or completely to the opposite margin. Fibulae are distinct and spaced evenly (5-6 in 10 µm). Striae are uniseriate, robust and distinctly punctate, with 2-3 rows between each fibulae. The girdle band is unornamented.

This taxon was confused with Nitzschia amphibia var. frauenfeldii in USGS surveys in the National Water Quality Assessment program (NAWQA). Both taxa are included in the diatom flora of the Everglades (Slate and Stevenson 2007).


This taxon was described from the Florida Everglades (Lange-Bertalot 1993).

The populations studied for this page were also collected in the Florida Everglades (2007, 2017). The Florida Everglades is a karstic freshwater wetland. Specimens were documented from periphyton, benthic mats, and epiphytic habitats. Water chemistry at the time of collection (2007): temperature (30.4°C); pH (6.79); conductivity (591 µS); (2017): temperature (26.6°C); pH (around 7.2); conductivity (232 µS).

Nitzschia Serpentiraphe Autoecology
Size range of N. serpentiraphe.

Original Description

Frustula aspectu cincturae rectangularis marginibus (rectinaculifromibus) incurvatis in medio. Limbi valvarum striati striis duplopunctatis et inter iallas, amgis valide libulis carinarum. Valve lineares unilaterialiter plusminusve incurvatae in medio apicibus cuneatiformibus et obtuse rotundatis, 40-80 µm longae, 5.5-7.5 µm latae. Carina raphis fibulis fere ad lineam mediam elongatis 5-6/10 µm. Striae transapicales 10-12/10 µm punctatae aspectibiles (in LM). A Nitzschia denticula differt singulari complexione signorum typicorum specialiter fissuris raphis extermis serpentiformibus interruptis in medio atque pseudoconopeum adest, i.e. velum adfixum marginem limbi contrarius carinam raphis.

Holotypus: Praep. Am-N 69 in Coll. Lange-Bertalot, Botan. Institut Universität Frankfurt a.M. (Fig. 126: 1-5)

Fundort des Holotypus: Everglades, Florida/USA, leg. Manfred Rumrich, 3.10.1991.

  • Author
    Lange-Bert. 1993
  • Length Range
    40-80 µm
  • Width
    5.5-7.5 µm
  • Striae in 10µm

Original Images

Nitzschia Serpentiraphe Orig Illus 02
Nitzschia Serpentiraphe Orig Desc

Cite This Page

Emery, M. (2018). Nitzschia serpentiraphe. In Diatoms of North America. Retrieved August 25, 2019, from https://diatoms.org/species/nitzschia-serpentiraphe


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