Nebela marginata
P. marginata, 185 um, stacked images – Austria

 

Planocarina marginata (Penard, 1902)

Diagnosis: shell is colorless, oval or pyriform, laterally compressed, composed mainly of oval or circular shell plates, often interspersed with small beads of organic cement; shell with a small lateral ridge that begins just posterior to the aperture; aperture oval and surrounded by a small but thickened lip.

Remarks: this species has a characteristic small lateral ridge, but the degree of development of this feature is not constant and probably indicates a wide range of variability. I have found P. carinata and P. marginata always together.

Nebela marginata
Nebela marginata
This shell contains some radial plate scales of an heliozoan species (arrows).The arrow indicates a radial scale of a heliozoon, used for the shell building.
Nebela marginata
Nebela marginata
The arrow indicates an aperture scale of an Euglypha species.

These shell has been build from xenosomes, like a fragment of a diatiom (left hand arrow), the spine scale of Euglypha acanthophora (upper arrow) and plate scales of an Heliozoon (right hand arrow).

Nebela marginata
P. marginata, 185 µm – stacked image
Nebela marginata
P. marginata, 185 µm
Nebela marginata, detail of shell
P. marginata, detail of a shell – stacked image
P. marginata, 184 µm, British Columbia
P. marginata, 159 um long – Tirol, Austria
P. marginata, 179 um long – Tirol, Austria

 
 
 

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