Ancyromonadida or Planomonadida is a small group of biflagellated eukaryotes found in the soil and in aquatic habitats, where they feed on bacteria. 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.
The group's placement is doubtful, as it seems to fall outside the five supergroups of eukaryotes. Cavalier-Smith considers that they constitute a basal group to Amoebozoa and Opisthokonta and places it together with other related groups in Sulcozoa. 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.
Phylogeny
Taxonomy
- Order Ancyromonadida <small>Cavalier-Smith 1998 emend. Atkins 2000</small>
- Family Planomonadidae <small>Cavalier-Smith 2008</small> (may be paraphyletic)
- Genus Fabomonas <small>Glücksman & Cavalier-Smith 2013</small>
- Species F. tropica <small>Glücksman & Cavalier-Smith 2013</small>
- Species F. mesopelagica <small>Yubuki et al. 2023</small>
- Genus Planomonas <small>Cavalier-Smith 2008 emend. Cavalier-Smith 2013</small>
- Species P. brevis <small>Glücksman & Cavalier-Smith 2013</small>
- Species P. bulbosa <small>Glücksman & Cavalier-Smith 2013</small>
- Species P. cephalopora <small>(Larsen & Patterson 1990) Cavalier-Smith 2008</small> [Bodo cephalopora <small>Larsen & Patterson 1990</small>; Ancyromonas cephalopora <small>(Larsen & Patterson 1990) Heiss, Walker & Simpson 2010</small>]
- Species P. elongata <small>Glücksman & Cavalier-Smith 2013</small>
- Species P. micra <small>Cavalier-Smith 2008</small> [Ancyromonas micra <small>(Cavalier-Smith 2008) Heiss, Walker & Simpson 2010</small>]
- Family Ancyromonadidae <small>Cavalier-Smith 1993</small> [Phyllomonadidae <small>Hada 1968</small>]
- Genus Ancyromonas <small>Kent 1880</small> [Phyllomonas <small>Klebs 1892</small>]
- Species A. abrupta <small>Skvortzov 1957</small>
- Species A. atlantica <small>Glücksman & Cavalier-Smith 2013</small>
- Species A. contorta <small>(Klebs 1883) Lemmermann 1914</small> [Phyllomonas contorta <small>Klebs 1883</small>]
- Species A. impluvium <small>Lee 2015</small>
- Species A. indica <small>Glücksman & Cavalier-Smith 2013</small>
- Species A. kenti <small>Glücksman & Cavalier-Smith 2013</small>
- Species A. lata <small>Skvortzov 1957</small>
- Species A. magna <small>Zhang & Yang 1993</small>
- Species A. mediterranea <small>Yubuki et al. 2023</small>
- Species A. metabolica <small>Skvortzov 1957</small>
- Species A. minuta <small>Skvortzov 1958</small>
- Species A. nitzschiae <small>Skvortzov 1957</small>
- Species A. pacifica <small>Yubuki et al. 2023</small>
- Species A. parasitica <small>Massart</small>
- Species A. prima <small>Skvortzov 1957</small>
- Species A. rotundata <small>Skvortzov 1957</small>
- Species A. rugosa <small>Skvortzov 1957</small>
- Species A. sigmoides <small>Kent 1880 sensu Heiss, Walker & Simpson 2010</small> [Planomonas mylnikovi <small>Cavalier-Smith 2008</small>]
- Species A. sinistra <small>Al-Qassab et al. 2002</small> [Planomonas sinistra <small>(Al-Qassab et al. 2002) Cavalier-Smith 2008</small>]
- Species A. socialis <small>Skvortzov 1957</small>
- Genus Caraotamonas <small>Yubuki et al. 2023</small>
- Species C. croatica <small>Yubuki et al. 2023</small>
- Genus Nutomonas <small>Cavalier-Smith 2013</small>
- Subgenus Nutomonas <small>Cavalier-Smith 2013</small>
- Species N. howeae <small>(Cavalier-Smith 2008) Glücksman & Cavalier-Smith 2013</small> [Planomonas howeae <small>Cavalier-Smith 2008</small>; Ancyromonas howeae <small>(Cavalier-Smith 2008) Heiss, Walker & Simpson 2010</small>]
- Subspecies N. h. howeae <small>(Cavalier-Smith 2008) Glücksman & Cavalier-Smith 2013</small>
- Subspecies N. h. lacustris <small>Glücksman & Cavalier-Smith 2013</small>
- Species N. limna <small>(Cavalier-Smith 2008) Glücksman & Cavalier-Smith 2013</small> [Planomonas limna <small>Cavalier-Smith 2008</small>; Ancyromonas limna <small>(Cavalier-Smith 2008) Heiss, Walker & Simpson 2010</small>]
- Subspecies N. l. limna <small>(Cavalier-Smith 2008) Glücksman & Cavalier-Smith 2013</small>
- Subspecies N. l. terrestris <small>Cavalier-Smith & Glücksman 2013</small>
- Genus Nyramonas <small>Yubuki et al. 2023</small>
- Species N. glaciarum <small>Yubuki et al. 2023</small>
- Species N. silfraensis <small>Yubuki et al. 2023</small>
- Genus Olneymonas <small>Yubuki et al. 2023</small>
- Species O. thurstoni <small>Yubuki et al. 2023</small>
- Genus Striomonas <small>Cavalier-Smith 2013 stat. nov. Yubuki et al. 2023</small>
- Species S. longa <small>Cavalier-Smith & Glücksman 2013 stat. nov. Yubuki et al. 2023</small>
- Incertae sedis Ancyromonadida
- Genus Divimonas <small>Barkhouse, Eglit, Weston and Simpson 2025</small>
- Species D. melba <small>(Simpson & Patterson 1996) comb. n. Barkhouse, Eglit, Weston and Simpson 2025</small> [Ancyromonas melba <small>Patterson & Simpson 1996</small>]
References
External links