Heliomonadida

The Heliomonadida<ref name="pmid18952499">Template:Cite journal</ref> (formerly Dimorphida<ref name="pmid15148395">Template:Cite journal</ref>) are a small group of heliozoan amoeboids that are unusual in possessing flagella throughout their life cycle.

Classification

Genetic studies place them among the Cercozoa, a group including various other flagellates that form filose pseudopodia. This order has recently been placed into the new class of naked filose cercozoans called Granofilosea.<ref name="pmid18952499"/> There are two genera in this order:

• Heliomorpha, a tiny organism found in freshwater
• the larger Tetradimorpha, which is distinguished by having four rather than two flagella.

Morphology

Bundles of microtubules, typically in square array, arise from a body near the flagellar bases and support the numerous axopods that project from the cell surface.

Dimorphids have a single nucleus, and mitochondria with tubular cristae.