Ancyromonadida or Planomonadida is a small group of biflagellatedprotists found in the soil and in aquatic habitats, where they feed on bacteria.[1][2] They are freshwater or marine organisms, benthic, dorsoventrally compressed and with two unequal flagellae, each emerging from a separate pocket. The apical anterior flagellum can be very thin or end in the cell membrane, while the posterior flagellum is long and is inserted ventrally or laterally. The cell membrane is supported by a thin single-layered theca and the mitochondrial crests are discoidal/flat.[3]
The group's placement is doubtful, as it seems to fall outside the five supergroups of eukaryotes.[4]Cavalier-Smith considers that they constitute a basal group to Amoebozoa and Opisthokonta and places it together with other related groups in Sulcozoa.[5] However, they appear more basal than Malawimonas, placing them in Loukozoa, possibly as stem podiates, and depending on the placement of the root position of the Eukaryotes.[6][7]
^Cavalier-Smith T, Chao EE, Stechmann A, Oates B, Nikolaev S (October 2008). "Planomonadida ord. nov. (Apusozoa): ultrastructural affinity with Micronuclearia podoventralis and deep divergences within Planomonas gen. nov". Protist. 159 (4): 535–62. doi:10.1016/j.protis.2008.06.002. PMID18723395.
^Adl, Sina M.; Simpson, Alastair G. B.; Lane, Christopher E.; Lukeš, Julius; Bass, David; Bowser, Samuel S.; Brown, Matthew W.; Burki, Fabien; Dunthorn, Micah; Hampl, Vladimir; Heiss, Aaron; Hoppenrath, Mona; Lara, Enrique; Le Gall, Line; Lynn, Denis H.; McManus, Hilary; Mitchell, Edward A. D.; Mozley-Stanridge, Sharon E.; Parfrey, Laura W.; Pawlowski, Jan; Rueckert, Sonja; Shadwick, Laura; Schoch, Conrad L.; Smirnov, Alexey; Spiegel, Frederick W. (2012). "The Revised Classification of Eukaryotes". Journal of Eukaryotic Microbiology. 59 (5): 429–514. doi:10.1111/j.1550-7408.2012.00644.x. PMC3483872. PMID23020233.
^ abGlücksman, Snell & Cavalier-Smith (2013). "Phylogeny and evolution of Planomonadida (Sulcozoa): Eight new species and new genera Fabomonas and Nutomonas". European Journal of Protistology. 49 (2): 179–200. doi:10.1016/j.ejop.2012.08.007. PMID23369787.
^ abcdefghijklmYubuki, Naoji; Torruella, Guifré; Galindo, Luis Javier; Heiss, Aaron A.; Ciobanu, Maria Cristina; Shiratori, Takashi; Ishida, Ken‐ichiro; Blaz, Jazmin; Kim, Eunsoo; Moreira, David; López‐García, Purificación; Eme, Laura (November 2023). "Molecular and morphological characterization of four new ancyromonad genera and proposal for an updated taxonomy of the Ancyromonadida". Journal of Eukaryotic Microbiology. 70 (6: e12997). doi:10.1111/jeu.12997. hdl:2117/404022. ISSN1550-7408.