monothalamea monothalamea "monothalamea" is a grouping of foraminiferans, traditionally consisting of all foraminifera with single-chambered tests. recent work has shown that the grouping is paraphyletic, and as such does not constitute a natural group; nonetheless, the name "monothalamea" continues to be used by foraminifera workers out of convenience. monothalamea image of a deep sea xenophyophore scientific classification domain: eukaryota clade: diaphoretickes clade: sar phylum: retaria infraphylum: foraminifera class: monothalameahaeckel, 1862, emend. pawlowski et al., 2013 orders and subtaxa incertae sedis "allogromiida" "astrorhizida" xenophyophorea tendal, 1972 reticulomyxa page, 1987, emend. huelsmann, 2014 genera incertae sedis flexammina voltski & pawlowski, 2015 leannia apothéloz-perret-gentil & pawlowski, 2014 nellya gooday, anikeeva, & pawlowski, 2010 classification "monothalamea" traditionally contains two groups, neither of which is currently considered to be monophyletic: "allogromiida" traditionally consists of all foraminifera which lack a mineralised test, instead having a test of tectin. recent work has shown that this grouping is paraphyletic. "astrorhizida" traditionally consists of all foraminifera with single-chambered, agglutinated tests. recent work has shown that this grouping is polyphyletic, as agglutinated tests have evolved from proteinaceous tests multiple times throughout foraminiferal evolution. recent molecular evidence has revealed that the deep-sea xenophyophores are in fact agglutinated, single-chambered foraminifera. molecular evidence has also revealed that the freshwater protist reticulomyxa is in fact a naked, testless foraminifera, and as such it has been included with "monothalameans" in scientific discussion. a 2013 molecular study using small subunit rdna concluded that known "monothalameans" made up at least 22 distinct living clades from marine environments with an additional four clades from freshwater edna.