Eunotia areniverma

Furey, Lowe and Johansen 2011      Category: Eunotioid
BASIONYM: Eunotia areniverma Furey, Lowe and Johansen 2011

Eucocconeis laevis

 

Eunotia bilii

LM scalebar = 10 µm = 40 pixels.



Observations

Contributor: Paula Furey - February 2011
Length Range: 32-59 µm
Width Range: 10.5-12.0 µm
Striae in 10 µm: 9-12 in the valve center, 12-14 near the apices

Description

The ventral margin is concave. The dorsal margin is broadly arched. The dorsal margin of smaller valves are more arched than the dorsal margin of larger valves. The apices are broadly rounded and usually unconstricted, though slightly constricted in the longer valves. The apices are set off by a change in slope of the dorsal margin. Helictoglossae are visible in the LM. One apical rimoportula is present at the center of the apex. Striae are mostly parallel and interrupted by a hyaline line at the ventral margin. Areolae are 28-30 in 10 µm.

Comparison of E. areniverma with E. monodon deserves further clarification. Siver et al. (2005, Plate 31: Figs 1- 4) illustrates specimens of E. monodon Ehrenberg which also possess broadly rounded ends. The dorsal margin becomes more sloped, with a more pronounced hump as frustules decrease in size. However, based on the original description, E. monodon has apices with more cuneate ends, such as the E. monodon illustrated in Patrick & Reimer (1966, Plate 11: Fig. 6) and Lange-Bertalot (1993, Taf. 22: Figs 6 -7). Eunotia monodon was described from North America and is found here along with E. monodontiforma Lange-Bertalot et Nörpel. When the name was adopted in Europe, it was used incorrectly to describe what should be E. major (W. Smith) Rabenhorst (see discussion in Lange-Bertalot 1993). This has created some confusion around the taxonomy of the E. monodon and the E. major groups. The ends of both E. major and E. monodontiforma are more set off from the rest of the valve relative to E. areniverma. The broadly rounded ends, less set off from the rest of the valve and the broadly arching dorsal margin are characteristic features of E. areniverma.



Original Description

Basionym: Eunotia areniverma
Author: Furey, Lowe and Johansen 2011
Length Range: 32-59 µm
Width Range: 10.5-12.0 µm
Striae in 10 µm: 9-12 in the center valve, 12-14 near the valve apices

Original Description

Valves concave on the ventral margin, convex on the dorsal margin with a central swelling, prominently swollen in smallest valves, 32-59 μm long, 10.5-12.0 μm wide. Ends broadly rounded, usually unconstricted, slightly constricted in longest valves, set off by a change in slope of the dorsal margin. Helictoglossae visible in light microscope. Rimoportula at one end of valve, at the center of the apex. Striae mostly parallel, interrupted by a hyaline line at the ventral margin, 9-12 in 10 μm in the valve center, 12-14 in 10 μm near the valve apices. Puncta 28-30 in 10 μm.

Original Images


Cite This Page:
Furey, P. (2011). Eunotia areniverma. In Diatoms of the United States. Retrieved November 24, 2014, from http://westerndiatoms.colorado.edu/taxa/species/eunotia_areniverma

Species: Eunotia areniverma

Contributor: Paula Furey

Reviewer: Pat Kociolek

Citations

Furey, P.C., Lowe, R.L. and Johansen, J.R. (2011). Eunotia Ehrenberg (Bacillariophyta) of the Great Smoky Mountains National Park, USA. Bibliotheca Diatomologica 56: 1-134.

Lange-Bertalot, H. (1993). 85 Neue taxa und uber 100 weitere neu definierte Taxa erganzend zur Subwasserflora von Mittleuropa. Bibliotheca Diatomologica 27, 454 p. Cramer, Berlin, Stuttgart.

Patrick, R.M. and Reimer, C.W. (1966). The Diatoms of the United States exclusive of Alaska and Hawaii, V. 1. Monographs of the Academy of Natural Sciences of Philadelphia 13.

Siver, P.A. and Hamilton, P.B. (2005). Observations on new and rare species of freshwater diatoms from Cape Cod, Massachusetts, USA. Canadian Journal of Botany 83:362-378.

Links & ID's

Index Nominum Algarum (INA)

California Academy of Sciences (CAS)

North American Diatom Ecological Database (NADED)

NADED ID:

Autecology Discussion

Currently only known from a bryophyte squeeze in a soil seep at a rock outcrop at the bottom of a dry water way along the Long Hungry Ridge Trail off the 20 – Mile Creek Trail in the Great Smoky Mountains National Park.