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Observations
| Observations: | Bart Van de Vijver |
|---|---|
| Length: | 50-100µm |
| Width: | 11-13µm |
| Striae: | 27-30 striae in 10µm |
Description:
Valves linear-lanceolate to rhombical-lanceolate with broadly rounded, subrostrate ends (L 50-100µm, W 11-13µm, 27-30 striae in 10µm). The structure of the raphosternum with the axial ribs closely resembles the typus generis (Frustulia saxonica) with a convex central nodule, maximum width 3-4µm. Transapical striae parallel to subparallel. Puncta placed in slightly undulating rows (33 in 10µm).
| Morphology: | Naviculoid |
|---|---|
| Distribution: |
Autecology:
Notes:
La Chaloupe, Ile de la Possession, Crozet Archipelago, Sample BM306 (coll. date 07/01/1998).F. subantarctica was found in both moss and water samples with a preference for submerged and floating mosses taken from running water (pH 7,7-8, specific conductance 45-70µS/cm). Valves were also found in the sediment of several small lakes but abundance never exceeded 2%.So far only recorded on Ile de la Possession.This new taxon resembles F. amphipleuroides and F. rhomboides but differs from both by several features. It lacks the concave central nodule and the isolated pores between the central endings, typical for F. amphipleuroides and has a more lanceolate outline, contrary to F. rhomboides that is more rhombic. Manguin described in 1954 F. pulchra var. lanceolata. Based on three pictures, shown in Bourrelly & Manguin (1954: fig88a-c) it is clear that the taxon described by Manguin should be considered as F. amphipleuroides. They all show the concave central thickening. The dimensions mentioned by Manguin in the text perfectly coincide with the dimensions for F. amphipleuroides. Therefore, we consider F. pulchra var. lanceolata to be a synonym of F. amphipleuroides and the valves we found on Ile de la Possession clearly belong to a new taxon, as has already been pointed out by Lange-Bertalot in his work on Navicula and Frustulia (2001).
Other sites with Frustulia subantarctica
- Ile de la Possession (moist habitats), Crozet Archipelago
Original Type Description
| Author: | Van de Vijver & Beyens |
|---|---|
| Length: | 50-100µm |
| Width: | 11-13µm |
| Striae: | 27-30 striae in 10µm |
Original Description:
Valves linear-lanceolate to rhombical-lanceolate with broadly rounded, subrostrate ends (L 50-100µm, W 11-13µm, 27-30 striae in 10µm). The structure of the raphosternum with the axial ribs closely resembles the typus generis (Frustulia saxonica) with a convex central nodule, maximum width 3-4µm. Transapical striae parallel to subparallel. Puncta placed in slightly undulating rows (33 in 10µm).
New combination
| Author: |
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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).
