Ancyromonadida or Planomonadida is a small group of
biflagellated protists
A protist () is any eukaryotic organism (that is, an organism whose cells contain a cell nucleus) that is not an animal, plant, or fungus. While it is likely that protists share a common ancestor (the last eukaryotic common ancestor), the exc ...
found in the soil and in aquatic habitats, where they feed on bacteria.
[Cavalier-Smith, T. (2013)]
Early evolution of eukaryote feeding modes, cell structural diversity, and classification of the protozoan phyla Loukozoa, Sulcozoa, and Choanozoa
European journal of protistology, 49(2), 115-178. Includes freshwater or marine organisms,
benthic
The benthic zone is the ecological region at the lowest level of a body of water such as an ocean, lake, or stream, including the sediment surface and some sub-surface layers. The name comes from ancient Greek, βένθος (bénthos), meaning " ...
, 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 layer teak and the mitochondrial crests are discoidal / flat.
The group's placement is doubtful, as it seems to fall outside the five supergroups of
eukaryote
Eukaryotes () are organisms whose cells have a nucleus. All animals, plants, fungi, and many unicellular organisms, are Eukaryotes. They belong to the group of organisms Eukaryota or Eukarya, which is one of the three domains of life. Bacter ...
s.
Cavalier-Smith
Thomas (Tom) Cavalier-Smith, FRS, FRSC, NERC Professorial Fellow (21 October 1942 – 19 March 2021), was a professor of evolutionary biology in the Department of Zoology, at the University of Oxford.
His research has led to disc ...
considers that they constitute a basal group to
Amoebozoa
Amoebozoa is a major taxonomic group containing about 2,400 described species of amoeboid protists, often possessing blunt, fingerlike, lobose pseudopods and tubular mitochondrial cristae. In traditional and currently no longer supported c ...
and
Opisthokonta and places it together with other related groups in
Sulcozoa.
[Ruggiero, M. A., Gordon, D. P., Orrell, T. M., Bailly, N., Bourgoin, T., Brusca, R. C., Cavalier-Smith, T., Guiry, M.D. y Kirk, P. M. (2015)]
A Higher Level Classification of All Living Organisms.
/ref> However, they appear more basal than Malawimonas, placing them in Loukouzoa, 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 2000Ancyromonas
''Ancyromonas'' is a genus of basal Eukaryote consisting of heterotrophic flagellates.
It includes the species ''Ancyromonas sigmoides'', first described by Saville Kent in 1880. The genus was rediscovered in modern times by Hänel in 1979.
T ...
'' 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. metabolica'' Skvortzov 1957
**** Species '' A. minuta'' Skvortzov 1958
**** Species '' A. nitzschiae'' Skvortzov 1957
**** Species '' A. parasitica'' Massart
**** Species '' A. prima'' Skvortzov1957
**** 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 '' Nutomonas'' Cavalier-Smith 2013
**** Subgenus (''Striomonas'') Cavalier-Smith 2013
***** Species '' N. longa'' Cavalier-Smith & Glücksman 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
References
External links
{{Taxonbar, from=Q9150820
Excavata
Scotokaryotes