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Tectofilosid
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 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''. This group was previously classified as the Gromiida or Gromiina. However, molecular studies separate '' Gromia'' 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 are not yet certain. In a recent classification, the group Tectofilosida was not used: Chlamydophryidae, Psammonobiotidae, Pseudodifflugiidae and Volutellidae were dispersally ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Thecofilosea
Thecofilosea is a class of unicellular testate amoebae belonging to the phylum Cercozoa. They are amoeboflagellates, organisms with flagella and pseudopodia, distinguished from other cercozoa by their scale-lacking test composed of organic material. They are closely related to the Imbricatea, a group of testate amoebae with tests composed of inorganic silica scales. Cell structure Thecofilosean organisms evolved from an ancestor with a robust extracellular theca made of organic material, unlike most other Cercozoa, which are usually naked or have inorganic silica scales. They present thin pseudopodia (filopodia) that emerge from a ventral groove. They also have two flagella which have been secondarily lost in Rhizaspidae and the tectofilosid amoebae, and are restricted to zoospores within the phaeodarian amoebae. They ancestrally glide on their posterior flagellum only and have a benthic distribution, but many lineages have evolved as planktonic swimmers, like the Ebriacea whi ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
