Orthoseira biportulata

Taxon ID: 293
Author: Van de Vijver & Beyens    
Basionym:
Synonym:

 

Images

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LM image scalebar = 10 µm = pixels not measured     

 

Observations

Observations: Bart Van de Vijver
Length: diameter 15-35µm
Width: height 4 8µm
Striae:

Description:

Valves cylindrical, forming long chains (Diameter 15-35µm, Mantle height 4 8µm, Diameter/Mantle height ratio <1). Valve mantle relatively small, clearly punctated with areolae arranged in parallel, straight rows. Linking spines present and quite large. Clearly visible in LM. The valve face is ornamented with fine areolae, located in radiate striae. Between the longer striae, shorter rows of poroids are present. The pore-free area in the middle is larger and contains always exactly 2 circular carinoportulae.

Morphology: Centric
Distribution:

Autecology:

 

Notes:

Vallée du Camp, Ile de la Possession, Crozet Archipelago, Sample BA208 (coll. date 21/02/2002).Only found in one soil sample, taken from a small cavern in the vicinity of the base. PH of the soil sample almost circumneutral. Conductivity fairly high (424 µS/cm). Nutrient and salinity levels are low.First record for the Subantarctic Region.This population of Orthoseira is quite uniform but differs highly from the more common O. roeseana (large spines visible in LM, only two carinoportulae). We believe that is should be considered as a new species but further research will be necessary to reveal its exact taxonomical position.

 

 

Other sites with Orthoseira biportulata

  • Ile de la Possession (moist habitats), Crozet Archipelago

Original Type Description

Author: Van de Vijver & Beyens
Length: diameter 15-35µm
Width: height 4 8µm
Striae:

Original Description:

Valves cylindrical, forming long chains (Diameter 15-35µm, Mantle height 4 8µm, Diameter/Mantle height ratio <1). Valve mantle relatively small, clearly punctated with areolae arranged in parallel, straight rows. Linking spines present and quite large. Clearly visible in LM. The valve face is ornamented with fine areolae, located in radiate striae. Between the longer striae, shorter rows of poroids are present. The pore-free area in the middle is larger and contains always exactly 2 circular carinoportulae.

 

New combination

Author:

 

Citations

Index Nominum Algarum (INA):

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  • The INA is a bibliographic reference "card file" for algal taxonomy, containing nearly 200,000 names of algae (in the broad sense).

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