Capsellina bryorum

 

Conosphaera plexiformis*
Temporary name till it is published. This could also be a Luffisphaera species

 

This small cercozoan came up in wet mounts kept in moist chambers for some days. I've found it at several locations in oligotrophic and mesotrophic fresh waters, like Crailoo and 't Loo, both in the Netherlands, and in a small stream in Bretagne, France. It  This cercozoan has filopodia, like Pseudodifflugia, and a bowl shaped test with a large aperture. The test is composed of particles which look like birds heads: a sphere with a pointed spine (see arrowheads), which in SEM show a triangular sheet with a network shaped structure (see below).

 

Some spines - SEM-photomicrograph Eckhard Voelcker

Spine - SEM-photomicrograph Eckhard Voelcker

Detail of a spine - SEM-photomicrograph Eckhard Voelcker
Capsellina bryorum
Capsellina bryorum
Arrowheads point to spines.
Specimen from Crailoo, the Netherlands and (r) from Bretagne, France
Small stream, Bretagne, France
Dorsal view, small stream, Bretagne, France; arrow points to spined element

 

Specimen from France
Arrow points to a sphere ('t Loo, the Netherlands)and a sharp point
Filopodia doesn't seem to come from a kind of pseudostome. Nucleus visible ('t Loo, the Netherlands)