Ancyromonadida

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 Cavalier-Smith 1998 emend. Atkins 2000 Family Planomonadidae Cavalier-Smith 2008 (may be paraphyletic) Genus Fabomonas Glücksman & Cavalier-Smith 2013 Species F. tropica Glücksman & Cavalier-Smith 2013 Species F. mesopelagica Yubuki et al. 2023 Genus Planomonas Cavalier-Smith 2008 emend. Cavalier-Smith 2013 Species P. brevis Glücksman & Cavalier-Smith 2013 Species P. bulbosa Glücksman & Cavalier-Smith 2013 Species P. cephalopora (Larsen & Patterson 1990) Cavalier-Smith 2008 [Bodo cephalopora Larsen & Patterson 1990; Ancyromonas cephalopora (Larsen & Patterson 1990) Heiss, Walker & Simpson 2010] Species P. elongata Glücksman & Cavalier-Smith 2013 Species P. micra Cavalier-Smith 2008 [Ancyromonas micra (Cavalier-Smith 2008) Heiss, Walker & Simpson 2010] Family Ancyromonadidae Cavalier-Smith 1993 [Phyllomonadidae Hada 1968] Genus Ancyromonas Kent 1880 [Phyllomonas Klebs 1892] Species A. abrupta Skvortzov 1957 Species A. atlantica Glücksman & Cavalier-Smith 2013 Species A. contorta (Klebs 1883) Lemmermann 1914 [Phyllomonas contorta Klebs 1883] Species A. impluvium Lee 2015 Species A. indica Glücksman & Cavalier-Smith 2013 Species A. kenti Glücksman & Cavalier-Smith 2013 Species A. lata Skvortzov 1957 Species A. magna Zhang & Yang 1993 Species A. mediterranea Yubuki et al. 2023 Species A. metabolica Skvortzov 1957 Species A. minuta Skvortzov 1958 Species A. nitzschiae Skvortzov 1957 Species A. pacifica Yubuki et al. 2023 Species A. parasitica Massart Species A. prima Skvortzov 1957 Species A. rotundata Skvortzov 1957 Species A. rugosa Skvortzov 1957 Species A. sigmoides Kent 1880 sensu Heiss, Walker & Simpson 2010 [Planomonas mylnikovi Cavalier-Smith 2008] Species A. sinistra Al-Qassab et al. 2002 [Planomonas sinistra (Al-Qassab et al. 2002) Cavalier-Smith 2008] Species A. socialis Skvortzov 1957 Genus Caraotamonas Yubuki et al. 2023 Species C. croatica Yubuki et al. 2023 Genus Nutomonas Cavalier-Smith 2013 Subgenus Nutomonas Cavalier-Smith 2013 Species N. howeae (Cavalier-Smith 2008) Glücksman & Cavalier-Smith 2013 [Planomonas howeae Cavalier-Smith 2008; Ancyromonas howeae (Cavalier-Smith 2008) Heiss, Walker & Simpson 2010] Subspecies N. h. howeae (Cavalier-Smith 2008) Glücksman & Cavalier-Smith 2013 Subspecies N. h. lacustris Glücksman & Cavalier-Smith 2013 Species N. limna (Cavalier-Smith 2008) Glücksman & Cavalier-Smith 2013 [Planomonas limna Cavalier-Smith 2008; Ancyromonas limna (Cavalier-Smith 2008) Heiss, Walker & Simpson 2010] Subspecies N. l. limna (Cavalier-Smith 2008) Glücksman & Cavalier-Smith 2013 Subspecies N. l. terrestris Cavalier-Smith & Glücksman 2013 Genus Nyramonas Yubuki et al. 2023 Species N. glaciarum Yubuki et al. 2023 Species N. silfraensis Yubuki et al. 2023 Genus Olneymonas Yubuki et al. 2023 Species O. thurstoni Yubuki et al. 2023 Genus Striomonas Cavalier-Smith 2013 stat. nov. Yubuki et al. 2023 Species S. longa Cavalier-Smith & Glücksman 2013 stat. nov. Yubuki et al. 2023 Incertae sedis Ancyromonadida Genus Divimonas Barkhouse, Eglit, Weston and Simpson 2025 Species D. melba (Simpson & Patterson 1996) comb. n. Barkhouse, Eglit, Weston and Simpson 2025 [Ancyromonas melba Patterson & Simpson 1996]

External links

• Data related to Ancyromonadida at Wikispecies