Arcella

Dorsal view of Arcella vulgaris, from Microworld.

Belongs within: Arcellinida.

Arcella is a genus of amoeboids with a rigid, chitinous test found in brackish to fresh water (Loeblich & Tappan 1964).

Characters (from Loeblich & Tappan 1964): Test membranous, transparent, chitinoid, punctate or minutely cancellate, rarely spinose, hemispherical, recurved at circular to crenulate aperture (av. diam. 70µ), young tests hyaline, adult brown; protoplasm centrally placed, attached to interior of test by threads of ectoplasm, may secrete gas vacuoles, to serve hydrostatic function, allowing individual to float, and later resorb vacuoles in order to settle; pseudopodia few, lobose, blunt; commonly binucleate, but in some species as many as 200 nuclei occur; 4 or more small contractile vacuoles; reproduction by "budding".

<==Arcella Ehrenberg 1832 (see below for synonymy) LT64
    |--*A. vulgaris Ehrenberg 1832 [=A. (*Euarcella) vulgaris, A. (*Sticholepis) vulgaris] LT64
    |--A. arcelloides (Playfair 1918) [=*Leptocystis arcelloides] LT64
    |--A. arenaria LB90
    |--A. artocrea Deflandre 1928 NM05
    |--A. atava Collin 1914 [=A. (*Antarcella) atava] LT64
    |--A. aureola (Ehrenberg 1837) [=*Cyphidium aureolum, A. (*Cyphidium) aureola] LT64
    |--A. catinus LB90
    |--A. dentata Ehr. 1830 W86
    |--A. discoides Ehr. 1843 W86 [incl. A. discoides var. scutelliformis TG03]
    |--A. excavata Cunningham 1919 TG03
    |--A. hemisphaerica C-SCL16
    |--A. peristicta Ehrenberg 1854 [=A. (*Heterocosmia) peristicta] LT64
    |--A. mitrata D01
    `--A. polypora [incl. A. polypora var. curvata Wailes 1913] TG03

Arcella Ehrenberg 1832 [=Arcellina Carter 1856, Euarcella Deflandre 1928, Sticholepis Ehrenberg 1872; incl. Antarcella Deflandre 1928, Cyphidium Ehrenberg 1837, Heterocosmia Ehrenberg 1872, Leptocystis Playfair 1918 non Jaeckel 1899; Arcellida, Arcellidae, Arcellinae, Arcellinea, Arcellineae, Arcellinina] LT64

*Type species of generic name indicated

REFERENCES

[C-SCL16] Cavalier-Smith, T., E. E. Chao & R. Lewis. 2016. 187-gene phylogeny of protozoan phylum Amoebozoa reveals a new class (Cutosea) of deep-branching, ultrastructurally unique, enveloped marine Lobosa and clarifies amoeba evolution. Molecular Phylogenetics and Evolution 99: 275–296.

[D01] Daday, E. 1901. Édesvizi mikroszkópi állatok [Mikroskopische Süsswasserthiere]. In: Horváth, G. (ed.) Zichy Jenő Gróf Harmadik Ázsiai Utazása [Dritte Asiatische Forschungsreise des Grafen Eugen Zichy] vol. 2. Zichy Jenő Gróf Harmadik Ázsiai Utazásának Állattani Eredményei [Zoologische Ergebnisse der Dritten Asiatischen Forschungsreise des Grafen Eugen Zichy] pp. 375–470. Victor Hornyánszky: Budapest, and Karl W. Hierseman: Leipzig.

[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.

[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.

[TG03] Todorov, M., & V. Golemansky. 2003. Morphology, biometry and ecology of Arcella excavata Cunningham, 1919 (Rhizopoda: Arcellinida). Acta Protozoologica 42: 105–111.

[W86] Whitelegge, T. 1886. List of the freshwater Rhizopoda of N. S. Wales. Part I. Proceedings of the Linnean Society of New South Wales, series 2, 1 (2): 497–504.