Pediglissa (from Ancient Greek πέδον 'soil' and French glisser 'to glide') is a subclass of phagotrophic protists that inhabit soil or freshwater habitats. They were defined in 2018 according to phylogenetic analyses that showed a clade containing the orders Cercomonadida and Glissomonadida. They're the sister group of Paracercomonadida.[1]

Pediglissa
Scientific classification Edit this classification
Domain: Eukaryota
Clade: Diaphoretickes
Clade: SAR
Phylum: Cercozoa
Class: Sarcomonadea
Subclass: Pediglissa
Cavalier-Smith, 2018[1]
Orders

Morphology and behavior

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Pediglissa are biciliate protists that glide on their posterior cilium and have a strong tendency to become amoeboid during feeding, unlike the metromonads. Their pseudopodia are more often shaped like rounded lamellae than finger-like or filose pseudopodia, unlike the paracercomonads. Their anterior cilium is often well developed, unlike in helkesids, but can be short in glissomonads; it moves with an undulating oar-like beat. The trophic cells (i.e. feeding forms) are naked, without a theca, scales, or perles, unlike in Thecofilosea and many freshwater Imbricatea.[1]

Diversity

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Pediglissa includes the majority of known cercozoan soil flagellates, all gliding on a single posterior cilium only:[1] the largely bacterivorous Cercomonadida, and the Glissomonadida[2] which include pansomonads and the algivorous Viridiraptoridae of recent description.[3]

References

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  1. ^ a b c d Cavalier-Smith, Thomas; Chao, Ema E.; Lewis, Rhodri (April 2018). "Multigene phylogeny and cell evolution of chromist infrakingdom Rhizaria: contrasting cell organisation of sister phyla Cercozoa and Retaria". Protoplasma. 255 (5): 1517–1574. doi:10.1007/s00709-018-1241-1. PMC 6133090. PMID 29666938.
  2. ^ Howe AT, Bass D, Vickerman K, Chao EE, Cavalier-Smith T (2009). "Phylogeny, Taxonomy, and Astounding Genetic Diversity of Glissomonadida ord. nov., The Dominant Gliding Zooflagellates in Soil (Protozoa: Cercozoa)". Protist. 160 (2): 159–189. doi:10.1016/j.protis.2008.11.007. ISSN 1434-4610.
  3. ^ Hess S, Melkonian M (2013). "The Mystery of Clade X: Orciraptor gen. nov. and Viridiraptor gen. nov. are Highly Specialised, Algivorous Amoeboflagellates (Glissomonadida, Cercozoa)". Protist. 164 (5): 706–747. doi:10.1016/j.protis.2013.07.003. ISSN 1434-4610.