Belongs within: Arcellinida.
The Centropyxiidae are a group of testate amoebozoans with a chitinous test into which sand or other foreign matter has been incorporated (Loeblich & Tappan 1964). In members of the genus Centropyxis the border of the pseudostome is bent inwardly whereas it is bent outwardly in Centropyxiella.
Characters (Loeblich & Tappan 1964): Test chitinous, enclosing some foreign material or with sandy layer, generally with dorsoventral symmetry; aperture ventral, with recurved margin, eccentric; single nucleus.
<==Centropyxiidae [Conchulina]
|--Marsipos Medioli et al. 1990HW93
|--Centropyxiella Valkanov 1970G86
| |--C. arenaria Valkanov 1970G86
| |--C. elegans Valkanov 1970G86
| |--C. gibbula Valkanov 1970G86
| |--C. gibbulina Chardez & Thomas 1980G86
| |--C. golemanskyi Chardez 1977G86
| |--C. lucida Golemansky 1971G86
| |--C. oopyxiformis Chardez 1977G86
| `--C. platystoma Golemansky 1981G86
`--Centropyxis Stein 1859 (see below for synonymy)LT64
|--*C. aculeata (Ehrenberg 1832)LT64 (see below for synonymy)
|--C. aerophila [incl. C. aerophila var. sphagnicola]LB90
|--C. cassisLB90 [incl. C. cassis var. spiniferaV63]
|--C. constricta [incl. C. constricta var. minima]LB90
|--C. discoidesV63
|--C. ecornisSX97
|--C. gasparellaLNB03
|--C. gibbaV63
|--C. globulosaLB90
|--C. hemisphaericaSX97
|--C. hirsutaSR06
|--C. kahliLNB03
|--C. laevigata Penard 1902NM05
|--C. marsupiformisN03
|--C. orbicularisLB90
|--C. plagiostomaLB90
|--C. platystomaLNB03
|--C. pleurostomelloides (Millett 1899) (see below for synonymy)LT64
|--C. pontigulasiformisLNB03
`--C. sylvaticaLB90 [=C. aerophila var. sylvaticaV63; incl. C. sylvatica var. minorLB90]
Centropyxis Stein 1859 [=Echinopyxis Claparède & Lachmann 1859; incl. Armillettum Rhumbler 1913, Millettella Rhumbler 1904]LT64
*Centropyxis aculeata (Ehrenberg 1832)LT64 [=Arcella aculeataLT64, *Echinopyxis aculeataLT64; incl. Centropyxis aculeata var. oblongaV63]
Centropyxis pleurostomelloides (Millett 1899) [=Reophax pleurostomelloides, *Armillettum pleurostomelloides, *Millettella pleurostomoides]LT64
*Type species of generic name indicated
References
[G86] Golemansky, V. G. 1986. Rhizopoda: Testacea. In: Botosaneanu, L. (ed.) Stygofauna Mundi: A Faunistic, Distributional, and Ecological Synthesis of the World Fauna inhabiting Subterranean Waters (including the Marine Interstitial) pp. 5–16. E. J. Brill/Dr. W. Backhuys: Leiden.
[HW93] Hart, M. B., & C. L. Williams. 1993. Protozoa. In: Benton, M. J. (ed.) The Fossil Record 2 pp. 43–70. Chapman & Hall: London.
[LNB03] Ledeganck, P., I. Nijs & L. Beyens. 2003. Plant functional group diversity promotes soil protist diversity. Protist 154 (2): 239–249.
[LT64] Loeblich, A. R., Jr & H. Tappan. 1964. Sarcodina: chiefly “thecamoebians” and Foraminiferida. In: Moore, R. C. (ed.) Treatise on Invertebrate Paleontology pt C. Protista 2 vol. 1. The Geological Society of America and The University of Kansas Press.
[LB90] Lousier, J. D., & S. S. Bamforth. 1990. Soil protozoa. In: Dindal, D. L. (ed.) Soil Biology Guide pp. 97–136. John Wiley & Sones: New York.
[N03] Nicholls, K. H. 2003. Form variation in Campascus minutus and a description of Campascus simcoei sp. n. (Testaceafilosea, Psammonobiotidae). European Journal of Protistology 39 (1): 103–112.
[NM05] Nikolaev, S. I., E. A. D. Mitchell, N. B. Petrov, C. Berney, J. Fahrni & J. Pawlowski. 2005. The testate lobose amoebae (order Arcellinida Kent, 1880) finally find theit home within Amoebozoa. Protist 156: 191–202.
[SR06] Schmidt, A. R., E. Ragazzi, O. Coppellotti & G. Roghi. 2006. A microworld in Triassic amber. Nature 444: 835.
[SX97] Song B. & Xie P. 1997. Preliminary studies on the community structure of the planktonic protozoa from the outlet of Lake Dongting. Acta Hydrobiologica Sinica 21 (Suppl): 60–68.
[V63] Varga, L. 1963. Weitere Untersuchungen über die aquatile Mikrofauna der Baradla-Höhle bei Aggtelek (Ungarn) (Biospeologica Hungarica, XVII). Acta Zoologica Academiae Scientiarum Hungaricae 9 (3–4): 439–458.