Heliomonadida

The Heliomonadida^[1] (formerly Dimorphida^[2]) are a small group of heliozoan amoeboids that are unusual in possessing flagella throughout their life cycle.

Heliomonadida
Heliomorpha mutans (= Dimorpha mutans), fig. 9-11
Scientific classification
Domain:	Eukaryota
Clade:	Sar
Clade:	Rhizaria
Phylum:	Cercozoa
Class:	Granofilosea
Order:	Heliomonadida Cavalier-Smith, 1993 emend. Cavalier-Smith, 2012
Family:	Heliomorphidae Cavalier-Smith & Bass 2009
Genera
Heliomorpha Cavalier-Smith & Bass 2009 Tetradimorpha Hsiung 1927

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.^[1] 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.