Mantamonas

Mantamonas
Scientific classification
Domain:	Eukaryota
Clade:	Opimoda
Clade:	CRuMs
Class:	Glissodiscea Cavalier-Smith 2013 emend. 2021[2]
Order:	Mantamonadida Cavalier-Smith 2011[1]
Family:	Mantamonadidae Cavalier-Smith 2011[1]
Genus:	Mantamonas Cavalier-Smith & Glücksman 2011[1]
Type species
Mantamonas plastica Glücksman & Cavalier-Smith 2011[1]
Species
Mantamonas plastica Mantamonas sphyraenae Mantamonas vickermani
Diversity
3 species[3]

Mantamonads are a group of free-living heterotrophic flagellates that move primarily by gliding on surfaces (rather than swimming). They are classified as one genus Mantamonas in the monotypic family Mantamonadidae, order Mantamonadida and class Glissodiscea.[2] Previously, they were classified in Apusozoa as sister of the Apusomonadida on the basis of rRNA analyses.[1][4] However, mantamonads are currently placed in CRuMs on the basis of phylogenomic analyses that identify their closest relatives as the Diphylleida and Rigifilida.[5][6]

Morphology

Mantamonas are heterotrophic unicellular protists. Their cells are flattened, relatively plastic and asymmetric. They have one thin anterior 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,[1] 5 μm long and 5 μm wide, but vary in size and shape depending on their growth phase and the bacterial density in the medium.[3] When wide-shaped, they present lateral "wings" that resemble the fins of a manta ray (hence the name Mantamonas).[3]

Ecology

Mantamonas are marine gliding heterotrophic flagellates. M. plastica was isolated from marine sediments, while M. vickermani was isolated from marine lagoon sediments. M. sphyraenae was obtained from the skin surface of a barracuda, suggesting that it could be an epizootic species.[3]

Evolution

When discovered in 2011, a phylogenetic analysis based on 28S and 18S rRNA recovered Mantamonas as a lineage closely related to Planomonadida and Apusomonadida, within the paraphyletic Apusozoa.[1] Later in 2018, a phylogenomic analysis recovered Mantamonas as the sister group of a clade comprising Collodictyonidae and Rigifilida. Together, the three groups compose the CRuMs clade, which is the sister group to Amorphea (Amoebozoa + Obazoa) in a clade known as Podiata.[6]

Eukaryota

Diaphoretickes Discoba Metamonada Cavalier-Smith 1987 emend. Cavalier-Smith 2003 Ancyromonadida Cavalier-Smith 1998 emend. Atkins 2000 Malawimonadea Cavalier-Smith 2003 Podiata Amorphea Amoebozoa Lühe 1913 emend. Cavalier-Smith 1998 Obazoa Breviatea Cavalier-Smith 2004 Apusomonadida Karpov & Mylnikov 1989 Opisthokonta CRuMs Mantamonadida   Mantamonas sphyraenae Mantamonas plastica Mantamonas vickermani Rigifilida Karpov & Mylnikov 1989 Diphylleida Cavalier-Smith 1993

Species

There are currently three species of Mantamonas.[3]

• Mantamonas plastica Glücksman & Cavalier-Smith 2011[1]
• Mantamonas sphyraenae Blaz et al. 2021
• Mantamonas vickermani Blaz et al. 2021

References

1. Glücksman, Edvard; Snell, Elizabeth A.; Berney, Cédric; Chao, Ema E.; Bass, David; Cavalier-Smith, Thomas (September 2010). "The Novel Marine Gliding Zooflagellate Genus Mantamonas (Mantamonadida ord. n.: Apusozoa)". Protist. 162 (2): 207–221. doi:10.1016/j.protis.2010.06.004. PMID 20884290.
2. Cavalier-Smith, Thomas (May 2022). "Ciliary transition zone evolution and the root of the eukaryote tree: implications for opisthokont origin and classification of kingdoms Protozoa, Plantae, and Fungi". Protoplasma. 259 (3): 487–593. doi:10.1007/s00709-021-01665-7. PMC 9010356. PMID 34940909.
3. Blaz, Jazmin; Galindo, Luis Javier; Heiss, Aaron A.; Kaur, Harpreet; Torruella, Guifré; Yang, Ashley; Thompson, L. Alexa; Filbert, Alexander; Warring, Sally; Narechania, Apurva; Shiratori, Takashi; Ishida, Ken-ichiro; Dacks, Joel B.; López-García, Purificación; Moreira, David; Kim, Eunsoo; Eme, Laura (January 2021). "High quality genome and transcriptome data for two new species of Mantamonas, a deep-branching eukaryote clade". bioRxiv. doi:10.1101/2023.01.20.524885.
4. Orr, Russell J. S.; Zhao, Sen; Klaveness, Dag; Yabuki, Akinori; Ikeda, Keiji; Makoto, Watanabe M.; Shalchian-Tabrizi, Kamran (2017-10-08). "Enigmatic Diphyllatea eukaryotes: Culturing and targeted PacBio RS amplicon sequencing reveals a higher order taxonomic diversity and global distribution". bioRxiv 10.1101/199125.
5. Cavalier-Smith, Thomas; Chao, Ema E.; Snell, Elizabeth A.; Berney, Cédric; Fiore-Donno, Anna Maria; Lewis, Rhodri (2014). "Multigene eukaryote phylogeny reveals the likely protozoan ancestors of opisthokonts (animals, fungi, choanozoans) and Amoebozoa". Molecular Phylogenetics and Evolution. 81: 71–85. doi:10.1016/j.ympev.2014.08.012. PMID 25152275.
6. Brown, Matthew W; Heiss, Aaron A; Kamikawa, Ryoma; Inagaki, Yuji; Yabuki, Akinori; Tice, Alexander K; Shiratori, Takashi; Ishida, Ken-Ichiro; Hashimoto, Tetsuo (January 2018). "Phylogenomics Places Orphan Protistan Lineages in a Novel Eukaryotic Super-Group". Genome Biology and Evolution. 10 (2): 427–433. doi:10.1093/gbe/evy014. ISSN 1759-6653. PMC 5793813. PMID 29360967.