• Category
  • Length Range
    12-50 µm
  • Width Range
    5.5-7.0 µm
  • Striae in 10 µm
    14-18
  • Reported As
    Gomphonema brasiliense (Wallace 1960, pg. 5, Pl. 2, Figs. 5A-D)
    Gomphonema brasilense (Patrick and Reimer 1975, pg. 143, Pl. 15, Figs. 15-17)

Identification

Description

Valves at the higher end of the size range are linear-clavate with undulate margins, while smaller valves are clavate with smooth margins. The headpole is narrowly rounded to nearly acute and the footpole is narrowly rounded. The axial area is lanceolate, narrow at the poles, and expanded towards the center. Stigmata are absent. The raphe is straight, filiform, and the external proximal raphe ends are dilated. The central nodule is distinct and round. The striae are formed by a single areola, with an additional 1-2 isolated areolae towards the axial area. The striae are radiate, becoming parallel near the footpoles. Septa and pseudosepta are absent.

The names Gomphonema brasiliense and Gomphosphenia lingulatiformis have been confused in the literature, as well as on the Diatoms of the US flora. To clarify the nomenclature:

  1. In 1878, Grunow published a new species, Gomphonema brasiliense, based on material collected from Brazil, Cuba and India. No holotype was designated, nor did his description include an illustration.

  2. In 1880, Van Heurck published two line drawings in his Atlas, labeled “G. (abbreviatum) var. brasiliense”, from Brazil and Cuba (T. 25, Fig. 17a-b).

  3. In 1985, Krammer and Lange-Bertalot proposed that the three syntype populations for G. brasiliense were not conspecific and lectotypified specimens from the Brazilian material, which was the first collection mentioned (and therefore had priority) in Grunow 1878. They published light micrographs of the lectotype population that strongly differ from Van Heurck’s line drawing. Krammer and Lange-Bertalot state that Van Heurck’s drawings derive from the Cuba population, which they considered G. grovei var. lingulatum.

  4. Gomphonema brasiliense and Gomphosphenia lingulatiformis taxon pages were opened in September 2011, documenting what appeared to be the same taxon under two different names. These two names for one taxon are incorrect, and the problem needs to be rectified.

The taxon G. brasiliense has not been confirmed in North America. Specimens illustrated by Patrick and Reimer (1975) and Wallace (1960), identified as G. brasilisense, were both revisited and were determined to conform to G. lingulatiformis. Furthermore, NAWQA and NRSA samples collected in rivers in the southeast U.S. with count records for G. brasiliense were reexamined in December 2016. For all reexamined slides, the relevant gomphonemoid diatom population on the slide was morphologically dissimilar to G. brasiliense sensu KLB (lectotype from Brazil). In contrast, these valves bear resemblance to the Van Heurck Atlas line drawing (T. 25, Fig. 17a-b), and more specifically like Gomphosphenia lingulatiformis (Lange-Bertalot and Reichardt) Lange-Bertalot 1995, a taxon described from France. We suggest that the Cuban syntype population of G. brasiliense is either G. lingulatiformis or a morphologically similar Gomphosphenia, and that this was the material upon which the Van Heurck line drawing is based.

Autecology

This diatom is relatively common throughout rivers of the southeast (USGS 2015 SESQA survey). In contrast, it was reported in only a few sites in western surveys (EPA 2000-2004 Western EMAP).

Original Description

  • Basionym
    Gomphonema lingulatiforme
  • Author
    Lange-Bert. and E.Reichardt in Lange-Bert. 1993

Updates

Jan 18, 2017 - Closure of synonymous G. brasiliense page and update of G. lingulatiformis page

Changes were made on January 18, 2017 to this page, which originally was published on September 20, 2011, to correct the conflicting taxon pages for Gomphonema brasiliense and Gomphosphenia lingulatiformis. Gomphosphenia lingulatiformis images were replaced with better quality images (including SEMs), and the G. brasiliense page was closed, as that taxon is South American in origin and has not been confirmed in North America (see Observations Section). The images now presented are considered to better reflect the G. lingulatiformis morphological concept and range of size. Gomphonema brasiliense has also been added to the “reported as” field in the updated G. lingulatiformis page. The archived version of the page for G. brasiliense is available upon request. - Ian Bishop

Cite This Page

Kociolek, P., Bishop, I. (2017). Gomphosphenia lingulatiformis. In Diatoms of North America. Retrieved November 11, 2024, from https://diatoms.org/species/gomphosphenia_lingulatiformis1

Responses

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