• Category
  • Length Range
    16.1-21.3 µm
  • Width Range
    2.9-3.3 µm
  • Striae in 10 µm



The valves are linear, slightly swollen in the center and at the ends. The axial area is straight and linear; the central area is round. The raphe terminates in a subapical nodule.


Original Description

Species subgeneris Paradiadesmis. Valvae stricte lineares in media parts parum inflatae apicibus late subcapitatis et late rotundatis, 20-35, longae, 3-4 μm latae. Raphe filiformis recta poris et nodulis terminalibus plus minusve valde de apicibus ad partem proximalem versus transferunt, itaque cum areis terminalibus angustis longs prolongatis. Area axialis angusta linearis, area centralis plerumque paene circularis modice ampla. Striae transapicales circum aream centralem radiatae aliis parallelis vel subparallelis, 25-27 in 10 μm.

  • Basionym
    Diadesmis pantropica
  • Author
    Lange-Bert. 2000
  • Length Range
    20-35 µm
  • Width
    3-4 µm
  • Striae in 10µm

Original Images

Diadesmis pantropica orig illus
Dipantropica  Orig Descr


Apr 16, 2024 - Transfer

This taxon original appeared on the Diatoms of US website under the genus Diadesmis. An update was made to reflect a transfer to the new genus, Humidophila. - S. Spaulding

Cite This Page

Lowe, R. (2011). Humidophila pantropica. In Diatoms of North America. Retrieved April 16, 2024, from https://diatoms.org/species/humidophila_pantropica


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