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Observations
| Observations: | Bart Van de Vijver |
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| Length: | 26-50 µm |
| Width: | 6-7 µm |
| Striae: | Central:14-16 in 10 µm, Distal: 19-21 in 10 µm |
Description:
Valves linear with a slightly gibbous centre. Valve margins straight and parallel between the valve centre and the apices, becoming broadly rounded at the ends. Valve length 26-50 µm, valve width 6-7 µm. Axial area rather broad, linear, clearly widening near the valve center to form an elliptical central area with a rectelevatum. Raphe filiform, straight with distinct unilaterally bent, rather short central raphe endings. Central raphe ends extending into the first 2-3 rows of areolae. Distal raphe endings deflected to the same side as the proximal ends lacking bifurcations. Centrally, striae radiate and more spaced whereas other striae almost parallel, to even convergent near the valve apices. Central striae number 14-16 in 10 µm and the distal striae number 19-21 in 10 µm. Striae composed of two types of areolae: the first 3 rows near the axial area composed of very small, rounded areolae whereas the other areolae, starting midway between the axial area and the valve mantle transapically elongated. Near the valve apices, 3-5 canal puncta present on each side of the axial area. Areolae covered internally by small rounded vela. When the vela are removed, areolae rounded near the axial area and transapically elongated towards the valve mantle. Longitudinal canal broad centrally but more riblike towards the apices, terminating at the helictoglossa. Apart from the canal puncta, no perforations of the longitudinal canals found.
| Morphology: | Naviculoid |
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| Distribution: |
Autecology:
Notes:
Muelleria australoatlantica shares several features with M. meridionalis, described from the Antarctic Continent, and M. varipunctata, found on some islands in the southern Indian Ocean. The species most similar to M. australoatlantica is M. varipunctata, which shares similar structure for both striae and areolae. However, the striae of *M. varipunctata* are composed of clearly enlarged areolae bordering the raphe (Spaulding et al. 1999). Moreover, M. varipunctata possesses bifurcating terminal raphe ends, whereas M. australoatlantica only presents non-divergent ends. Muelleria meridionalis, on the other hand, has a raphe structure similar to M. varipunctata but with a different valve outline having more undulating margins between the gibbous valve center and the apices. The structure of the striae with both small, rounded areolae and larger, transapically elongated areolae, typical for M. australoatlantica, is never observed in M. meridionalis. Additionally, M. meridionalis usually has one canal punctum on each side of the raphe whereas in M. australoatlantica, 3-5 canal puncta are found.
Other sites with Muelleria austroatlantica
- Bellingshausen Station (moist habitats), King George Island
- Fumarole Bay (soil), Deception Island
- James Ross Island (soil), James Ross Island
Original Type Description
| Author: | Van de Vijver & Spaulding 2009 |
|---|---|
| Length: | 26-50 µm |
| Width: | 6-7 µm |
| Striae: | Central:14-16 in 10 µm, Distal: 19-21 in 10 µm |
Original Description:
Valvae lineares, paene rectae parte centrale leviter gibbosa, marginibus parallellis inter centrum valvae et apices late rotundatos. Longitudo 26-50 µm, latitudo 6-7 µm. Area axialis potius lata, linearis, claro dilatans in aream centralem ellipticam. Rectelevatum adest. Raphe filiformis, recta terminationibus centralis curtis, claro unilateraliter flexis, extensis in seriem secundum vel tertium areolae. Terminationes distales deflexae, numquam bifurcatae. Striae in parte centrale claro radiatae, 14-16 in 10 µm; parallellae ad convergentes ad apices, 19-21 in 10 µm. In seriebus tribus areolarum prope aream axialem, areolae parvissimae adsunt. Ad margines valvae, areolae transapicaliter elongatae. 3-5 puncta canales adsunt.
New combination
| Author: |
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Citations
Index Nominum Algarum (INA):
- Original
- New Combination
- 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).
