Mantamonads are a group of free-living heterotrophic

flagellate A flagellate is a cell or organism with one or more whip-like appendages called flagella. The word ''flagellate'' also describes a particular construction (or level of organization) characteristic of many prokaryotes and eukaryotes and the ...

s that move primarily by gliding on surfaces (rather than swimming). They are classified as one

genus Genus (; : genera ) is a taxonomic rank above species and below family (taxonomy), family as used in the biological classification of extant taxon, living and fossil organisms as well as Virus classification#ICTV classification, viruses. In bino ...

''Mantamonas'' in the monotypic

family Family (from ) is a Social group, group of people related either by consanguinity (by recognized birth) or Affinity (law), affinity (by marriage or other relationship). It forms the basis for social order. Ideally, families offer predictabili ...

Mantamonadidae, order Mantamonadida,

class Class, Classes, or The Class may refer to: Common uses not otherwise categorized * Class (biology), a taxonomic rank * Class (knowledge representation), a collection of individuals or objects * Class (philosophy), an analytical concept used d ...

Glissodiscea and

phylum In biology, a phylum (; : phyla) is a level of classification, or taxonomic rank, that is below Kingdom (biology), kingdom and above Class (biology), class. Traditionally, in botany the term division (taxonomy), division has been used instead ...

Mantamonadea.Guiry, M.D. & Guiry, G.M. 2025. ''AlgaeBase''. World-wide electronic publication, University of Galway. https://www.algaebase.org; searched on 12 June 2025. Previously, they were classified in Apusozoa as sister of the Apusomonadida on the basis of rRNA analyses. However, mantamonads are currently placed in CRuMs on the basis of phylogenomic analyses that identify their closest relatives as the Diphylleida and Rigifilida.

Morphology

''Mantamonas'' are heterotrophic unicellular

protist A protist ( ) or protoctist is any eukaryotic organism that is not an animal, land plant, or fungus. Protists do not form a natural group, or clade, but are a paraphyletic grouping of all descendants of the last eukaryotic common ancest ...

s. Their cells are flattened, relatively plastic and asymmetric. They have one thin

anterior Standard anatomical terms of location are used to describe unambiguously the anatomy of humans and other animals. The terms, typically derived from Latin or Greek roots, describe something in its standard anatomical position. This position pro ...

flagellum and one conspicuous posterior flagellum, on which they glide. The cells have a right hump, likely caused by the nucleus, and a blunt projection on the left side. They are typically 2 μm thick, 5 μm long and 5 μm wide, but vary in size and shape depending on their growth phase and the

bacteria Bacteria (; : bacterium) are ubiquitous, mostly free-living organisms often consisting of one Cell (biology), biological cell. They constitute a large domain (biology), domain of Prokaryote, prokaryotic microorganisms. Typically a few micr ...

l density in the medium. When wide-shaped, they present lateral "wings" that resemble the fins of a manta ray (hence the name ''Mantamonas'').

Ecology

''Mantamonas'' are marine

gliding Gliding is a recreational activity and competitive air sports, air sport in which pilots fly glider aircraft, unpowered aircraft known as Glider (sailplane), gliders or sailplanes using naturally occurring currents of rising air in the atmospher ...

heterotrophic

s. '' M. plastica'' was isolated from marine sediments, while '' M. vickermani'' was isolated from marine

lagoon A lagoon is a shallow body of water separated from a larger body of water by a narrow landform, such as reefs, barrier islands, barrier peninsulas, or isthmuses. Lagoons are commonly divided into ''coastal lagoons'' (or ''barrier lagoons'') an ...

sediments. '' M. sphyraenae'' was obtained from the skin surface of a

barracuda A barracuda is a large, predatory, ray-finned, saltwater fish of the genus ''Sphyraena'', the only genus in the family Sphyraenidae, which was named by Constantine Samuel Rafinesque in 1815. It is found in tropical and subtropical oceans worldw ...

, suggesting that it could be an

epizootic In epizoology, an epizootic (or epizoötic, from Greek: ''epi-'' "upon" + ''zoon'' "animal") is a disease event in a nonhuman animal population analogous to an epidemic in humans. An epizootic disease (or ) may occur in a specific locale (an ...

species.

Evolution

When discovered in 2011, a phylogenetic analysis based on 28S and

18S rRNA 18S ribosomal RNA (abbreviated 18S rRNA) is a part of the ribosomal RNA in eukaryotes. It is a component of the Eukaryotic small ribosomal subunit (40S) and the cytosolic homologue of both the 12S rRNA in mitochondria and the 16S rRNA in plas ...

recovered ''Mantamonas'' as a lineage closely related to Planomonadida and Apusomonadida, within the

paraphyletic Paraphyly is a taxonomic term describing a grouping that consists of the grouping's last common ancestor and some but not all of its descendant lineages. The grouping is said to be paraphyletic ''with respect to'' the excluded subgroups. In co ...

Apusozoa. Later in 2018, a phylogenomic analysis recovered ''Mantamonas'' as the

sister group In phylogenetics, a sister group or sister taxon, also called an adelphotaxon, comprises the closest relative(s) of another given unit in an evolutionary tree. Definition The expression is most easily illustrated by a cladogram: Taxon A and ...

of a clade comprising Collodictyonidae and Rigifilida. Together, the three groups compose the CRuMs clade, which is the sister group to Amorphea (

Amoebozoa Amoebozoa is a major Taxonomy (biology), taxonomic group containing about 2,400 described species of Amoeba, amoeboid protists, often possessing blunt, fingerlike, Pseudopod#Morphology, lobose pseudopods and tubular mitochondrial cristae. In trad ...

+ Obazoa) in a clade known as Podiata.

Species

There are currently three species of ''Mantamonas''. *'' Mantamonas plastica'' * '' Mantamonas sphyraenae'' * '' Mantamonas vickermani''

References

{{Taxonbar, from1=Q24048470, from2=Q120002015, from3=Q120002005 CRuMs genera