The tectofilosids are a group of filose

amoeba An amoeba (; less commonly spelled ameba or amœba; plural ''am(o)ebas'' or ''am(o)ebae'' ), often called an amoeboid, is a type of cell or unicellular organism with the ability to alter its shape, primarily by extending and retracting pseudop ...

e with shells. These are composed of organic materials and sometimes collected debris, in contrast to the

euglyphid The euglyphids are a prominent group of filose amoebae that produce shells or tests from siliceous scales, plates, and sometimes spines. These elements are created within the cell and then assembled on its surface in a more or less regular arran ...

s, which produce shells from siliceous scales. The shell usually has a single opening, but in '' Amphitrema'' and a few other genera it has two on opposite ends. The cell itself occupies most of the shell. They are most often found on marsh plants such as ''

Sphagnum ''Sphagnum'' is a genus of approximately 380 accepted species of mosses, commonly known as sphagnum moss, peat moss, also bog moss and quacker moss (although that term is also sometimes used for peat). Accumulations of ''Sphagnum'' can store wa ...

''. This group was previously classified as the Gromiida or Gromiina. However, molecular studies separate ''

Gromia ''Gromia'' is a genus of protists, closely related to foraminifera, which inhabit marine and freshwater environments. It is the only genus of the family Gromiidae. ''Gromia'' are ameboid, producing filose pseudopodia that extend out from the ce ...

'' from the others, which must therefore be renamed. They are placed among the Cercozoa, and presumably developed from flagellates like '' Cryothecomonas'', which has a similar test. However, only a few have been studied in detail, so their relationships and

monophyly In cladistics for a group of organisms, monophyly is the condition of being a clade—that is, a group of taxa composed only of a common ancestor (or more precisely an ancestral population) and all of its lineal descendants. Monophyletic gro ...

are not yet certain. In a recent classification, the group Tectofilosida was not used: Chlamydophryidae, Psammonobiotidae,

Pseudodifflugiidae ''Pseudodifflugia'' is a genus of Cercozoa Cercozoa is a phylum of diverse single-celled eukaryotes. They lack shared morphological characteristics at the microscopic level, and are instead defined by molecular phylogenies of rRNA and actin ...

and Volutellidae were dispersally placed in Thecofilosea, while Amphitremidae was included in Labyrinthulomycetes.

Taxonomy

* Order

Tectofilosida The tectofilosids are a group of filose amoebae with shells. These are composed of organic materials and sometimes collected debris, in contrast to the euglyphids, which produce shells from siliceous scales. The shell usually has a single open ...

Cavalier-Smith & Chao 2003 (paraphyletic) ** Suborder Lithocollina Cavalier-Smith 2012 *** Family Lithocollidae Schulze 1874 ** Suborder Unitremina Cavalier-Smith 2012 *** Family Rhizaspididae Howe et al. 2011 hizaspidaceae Skuja 1948*** Family Fiscullidae Dumack et al. 2017 *** Family

De Saedeleer 1934 *** Family Psammonobiotidae Golemansky 1974 emend Meisterfeld 2002 *** Family Chlamydophryidae de Saedeleer 1934 emend. Meisterfeld 2002 *** Family Volutellidae Sudzuki 1979

References

{{Taxonbar, from=Q7692831 Filosa Amoeboids