Pansomonad

The pansomonads, suborder Pansomonadina (known before as order Pansomonadida), are a group of heterotrophic protists that belong to the phylum Cercozoa.^[1] Some of them are helioflagellates, with characteristics of heliozoans and amoebo-flagellates.^[2]

Pansomonad
Scientific classification
Domain:	Eukaryota
Clade:	Sar
Clade:	Rhizaria
Phylum:	Cercozoa
Class:	Sarcomonadea
Order:	Glissomonadida
Suborder:	Pansomonadina Vickerman, 2005 stat. nov. Cavalier-Smith, 2018
Families
Acinetactidae Agitatidae Aurigamonadidae Viridiraptoridae

Morphology and ecology

They are gliding phagotrophs that inhabit the soil and, unlike Allapsina, typically form rounded lamellar pseudopodia (= lamellipodia) that spread over surfaces. They have two dense rhizoplasts linked with each mature centriole. Their centrioles are orthogona or parallel to each other. The transition zone of their cilia has a dense distal plate. They are either bacterivorous or algivorous—bacterivorous forms may have haptopodia.^[1]

Classification

Before they became a suborder of Glissomonadida, pansomonads formed a separate order called Pansomonadida. Phylogenetic analyses consistently showed that the two orders were sister groups, and it was proposed that pansomonads had evolved from glissomonads. At the same time, Viridiraptoridae was recovered as more closely related to the known pansomonads at the time than to any other glissomonad, which prompted the inclusion of viridiraptorids within pansomonads.^[3] The current taxonomy of the pansomonads is:^[1]

• Family Acinetactidae Stokes, 1886
  • Acinetactis Stokes, 1886
• Family Agitatidae Cavalier-Smith & Bass, 2009
  • Agitata Cavalier-Smith & Bass, 2009
• Family Aurigamonadidae Cavalier-Smith, 2011
  • Aurigamonas Vickerman, 2005
• Family Viridiraptoridae Hess & Melkonian, 2013
  • Viridiraptor Hess & Melkonian, 2013
  • Orciraptor Hess & Melkonian, 2013