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LM image scalebar = 10 µm = 72 pixels
SEM image scalebar = 1 µm
Observations
| Observations: | Sarah Spaulding and Rhea Esposito |
|---|---|
| Length: | 15-37 µm |
| Width: | 3.5-5 µm |
| Striae: | 22-24 in 10 µm |
Description:
Valve margins linear and triundulate, the median portion slightly swollen; ends are subcapitate. Axial area distinct, widening into a broadly rounded central area (this central area is reduced in smaller specimens). Raphe straight, terminal nodules distinct. Striae radiate at the center of the valve and convergent at the ends; becoming shorter in length around the broad central area.
| Morphology: | Naviculoid |
|---|---|
| Distribution: | East Antarctic endemic |
Autecology:
Notes:
We observe four distinct valve morphologies in diatoms within the species of Chamaepinnularia found in the McMurdo Dry Valleys: undulate, capitate, linear, and spathulate valve margins. Although these morphs have been described as Navicula cymatopleura West et West, N. deltaica Kellogg et Kellogg, N. quaternaria Kellogg et Kellogg and referred to as Pinnularia cymatopleura var. #3 (Spaulding et al. 2007) respectively, we considered the taxa to be synonyms of P. cymatopleura (Spaulding et al. 1997). Examination of populations in Northern Victorialand showed no discontinuities between morphometic measurements that would indicate discrete populations (Cavacini et al. 2006). Based on the same paper, it appears that type slides do not exist for any of the three taxa. Cavacini et al. (2006) imply that a type specimen for C. cymatopleura does not exist, because they reported slides from West and West where C. cymatopleura was found, but not the type slides or locations. It also appears that type slides for N. deltaica and and N. quaternaria were not deposited at ANSP, as reported in Kellogg et al. (1980). Although these morphs do not appear to be distinct species, they occur at different sites in the streams of the McMurdo Dry Valleys. We continue to separate the morphs in our ecological analyses, because they may indicate different responses to environment, and are therefore useful in ecological analyses.
McMurdo Dry Valleys Waterbodies with Chamaepinnularia cymatopleura
- Aiken Creek
- Blue Lake
- Bowles Creek
- Canada Stream
- Clear Lake
- Coast Lake
- Commonwealth Stream
- Delta Stream
- Green Creek
- Harnish Creek Tributary
- Huey Creek
- Lake Fryxell
- Lost Seal Stream
- Many Glaciers Pond
- McMurdo Hut Ridge
- Miers Stream
- Parera Pond
- Picture Pond
- Pond by Blue Lake
- Pond by Clear Lake
- Pond South of Nussbaum Riegel
- Pony Lake
- Spaulding Pond
- Upland Pond
- Von Guerard Stream
- Wales Stream
- Wharton Creek
- Wormherder Creek
Original Type Description
| Author: | West & West 1911 |
|---|---|
| Length: | 17-27 µm |
| Width: | 4-5 µm |
| Striae: | 20-21 in 10 µm |
Original Description:
N. minutissima, valvis sublinearis, diametro 4.25-5.4 plo longioribus, lateribus triundulatis, undulo mediana levissime majori, polis subcapitatis, platea centrail magna et longitudinaliter elliptica, platea axiali lata, striis brevibus et lævibus, 20-21 in 10 µm, leviter radiatis, in parte mediana (adversus plateam centralem) brevioribus. Long. 17-27 µm; lat. 4-5 µm.
New combination
| Author: | Cavacini et al. 2006 |
|---|
Citations
Index Nominum Algarum (INA):
- Original
- If an INA link is available, it will be shown above
- The INA is a bibliographic reference "card file" for algal taxonomy, containing nearly 200,000 names of algae (in the broad sense).
Publications (by year):
- West and West 1911. p. 285, pl. 26, fig. 129. [citation 124(108)]
- Kellogg et al. 1980. p. 185, Pl. 1, Fig. 30. [citation 64(34)]
- Esposito et al. 2008. Botany 86: 1378-1392. [citation 137(137)]
