Diatoms of North AmericaDiatoms of North America

Geissleria punctifera

(Hust.) Metzeltin, Lange-Bert. and García-Rodríguez 2005

Geissleria Punctifera Guide2
  • Category
    Symmetric Biraphid
  • Length Range
    16-27 µm
  • Width Range
    6.0-8.5 µm
  • Striae in 10 µm
    16-18
  • Reported As
    Navicula aikenensis (Patrick 1959)
    Geissleria aikenesis ((Patrick) Torgan and Oliveira 2001)
    Geissleria schmidiae (Lange-Bert. and Rumrich in Rumrich et al. 2000)

Identification

Geissleria punctifera LM4 Geissleria punctifera LM2 Geissleria punctifera LM5 Geissleria punctifera LM1 Geissleria punctifera LM3
View image metadata Type
Geissleria punctifera SEM1

Description

Valves are lanceolate with subrostrate broadly rounded ends, 6.0-8.5 µm wide and 16-27 µm long. The raphe is straight and filiform. The axial area is narrow and linear. The central area is small, formed by one shortened stria on each side of the valve, with an isolated stigma. Striae are uniseriate, radiate, 16-18 in 10 µm. Areolae are apically elongated, 65-70 in 10 µm. Subpolar areolae, or annulae, are larger than areolae on other parts of the valve. The annulae form three rows at each pole.

Geissleria aikenensis (Patrick) Torgan and Oliveira 2001 is a later homonym of G. punctifera, and G. punctifera has priority over G. aikenensis (Potapova 2010, 2013). The holotype slide housed at the Academy of Natural Sciences of Philaldelphia for Navicula aikenensis (originally spelled “aikenenses”) was examined by Torgan and Oliveira (2001).

Autecology

Apparently, G. punctifera has a Western Hemisphere distribution. Hustedt described Navicula punctifera from a river in Brazil. More recent records reported it from additional locations in South America (Rumrich et al. 2000). In North America, it has been reported from rivers in the southeast U.S. (Potapova 2010, 2013) and California.

Original Description

Valvae elliptico-lanceolatae apicibus obtuse rostratis, 15— 23 μ longae, 6—9 μ latae. Rhaphe directa, area axialis anguste linearis, area centralis parva, rotundata vel irregulariter dilatata. Striae transapicales radiantes, 16—18 in 10 μ, in media parte interdum striis brevioribus intercalatis, delicatissime lineolatae vel punctatae. Area centralis uno latere cum poro singulo.

  • Basionym
    Navicula punctifera
  • Author
    Hust. 1952
  • Length Range
    15-23 µm
  • Width
    6-9 µm
  • Striae in 10µm
    16-18

Original Images

Orig Ill Napunct
Orig Descr Napunct

Cite This Page

Potapova, M. (2010). Geissleria punctifera. In Diatoms of North America. Retrieved November 21, 2024, from https://diatoms.org/species/geissleria_punctifera

Responses

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