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Reticulomyxa filosa
Main cell body

Reticulomyxa sp.?

I found this large naked amoeboid when it was crawling out of the hollow leg of a dead insect. It was extremely long and thin but at the end all plasm came together and formed a more or less massive cell with some holes in between. Because it was in the middle of of debris, it was nearly impossible to make sufficient observations and good pictures. It did not move after it moved from the tube to the debris. In the beginning it had some very long granuloreticulopodia, that stretched out of the debris, up to 1 mm each. Later, it retracted the pseudopodia and became more stationary. It did not move for hours, there was no streaming of cytoplasm anymore. The next day it was still there and the plasm was streaming again, with some long granulopodia with bi-directional streaming of granules. The next day, the organism was gone, probably hidden somewhere between debris.

I’m not sure wether this is a Reticulomyxa spec. or another freshwater foraminifer.

This specimen was sampled from organic sediment in the shallow part of the river Gard along camping Beau Rivage, Cardet, in France, 2019. The material covered the bed of the river, which was a mass of large pebbles. At home, I made some wet mounts and searched through the slides daily. I found this amoeboid after three days in a wet mount.

Reticulomyxa filosa
Stationary stadium
Reticulomyxa filosa
Granuloreticulopodia
Reticulomyxa filosa
Stationary but active form
Reticulomyxa filosa
Stationary but active form
Reticulomyxa filosa
A long ribbon of plasm, migration phase
Reticulomyxa filosa
The hollow leg of an insect where it crawled out.
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