Gymnophryid

The gymnophryids are a small group of amoeboids that lack shells and produce thin, reticulose pseudopods. These contain microtubules and have a granular appearance, owing to the presence of extrusomes, but are distinct from the pseudopods of Foraminifera. They are included among the Cercozoa, but differ from other cercozoans in having mitochondria with flat cristae, rather than tubular cristae.

Gymnophrys cometa, found in freshwater and soil, is representative of the group. The cell body is under 10 &mu;m in size, and has a pair of reduced flagella, which are smooth and insert parallel to one another. It may also produce motile zoospores and cysts. Gymnophrys and Borkovia are the only confirmed genera, but other naked reticulose amoebae such as Biomyxa may be close relatives.