Gomphonema elongatum
W. Smith 1855 Category: Asymmetrical biraphid
BASIONYM: Gomphonema elongatum W. Smith 1855
SYNONYM(S): Gomphonema acuminatum var. elongatum (W. Smith) Carruthers 1864
LM scalebar = 10 µm = 40 pixels.
Observations
Contributor: Pat Kociolek - September 2011
Length Range: 40-105 µm
Width Range: 7-11 µm
Striae in 10 µm: 13-15
Description
Valves acuminate-apiculate. The apex is protracted and blunt with a weakly expanded headpole. The central portion of the valve is tumid. The axial area is straight and wider at the apices than at the central valve. The central area is transversely widened, formed by two (one on each side) shortened central striae, and on one side is positioned a single isolated stigma. The punctate striae are radiate about the center, becoming parallel towards the ends, then becoming radiate at the headpole and footpole. The striae at the central valve are more widely spaced than the rest of the striae.
Original Description
Basionym: Gomphonema elongatum
Author: W. Smith 1855
Length Range: µm
Striae in 10 µm:
Original Description
Original Images
Cite This Page:
Kociolek, P. (2011). Gomphonema elongatum . In Diatoms of the United States. Retrieved May 22, 2013, from http://westerndiatoms.colorado.edu/taxa/species/gomphonema_elongatum
Species: Gomphonema elongatum
Contributor: Pat Kociolek
Reviewer: Rex Lowe
Image Credit: Pat Kociolek
- Headpole weakly expaned with protracted apex
- Central valve tumid
- Valves acuminate-apiculate
- 40-105 µm long
Valves acuminate-apiculate, with the headpole weakly expanded and protracted. The central valve is tumid. Both of the central striae are shortened, and on one side is positioned a single, isolated stigma.
Compare
Gomphonema elongatum is present in the eastern US. It is distinguished from both G. acuminatum and G. coronatum by its more linear outline.
Gomphonema acuminatum
Gomphonema coronatum
Citations
Patrick, R.M. and Reimer, C.W. (1975). The Diatoms of the United States, exclusive of Alaska and Hawaii, V. 2. Monographs of the Academy of Natural Sciences of Philadelphia 13.
Links & ID's
Index Nominum Algarum (INA)
California Academy of Sciences (CAS)
North American Diatom Ecological Database (NADED)
NADED ID: