Arcella peruviana sp. nov. (Amoebozoa: Arcellinida, Arcellidae), a new species from a tropical peatland in Amazonia

Eur J Protistol. 2015 Oct;51(5):437-49. doi: 10.1016/j.ejop.2015.01.002. Epub 2015 Feb 3.


There has only been one study on the ecology of testate amoebae from Amazonian peatlands, despite Amazonia being a biodiversity hotspot of global importance. During analysis of litter samples from Aucayacu peatland, western (Peruvian) Amazonia, we discovered a testate amoeba with a distinct morphology unlike any other species reported previously. We describe a new species, Arcella peruviana, based on its distinct morphology, compare it to morphologically similar species and provide information about its ecology. This new species is characterised by a distinct cruciform aperture (diameter ranges between 12 and 17μm) which is slightly invaginated. The test is small (height 43-57μm) and polygonal in cross-section. Our discovery suggests the existence of an unknown diversity of testate amoebae in Amazonia. The absence of the new Arcella species in more intensively-sampled regions supports the view that protists have restricted distributions.

Keywords: Microbial diversity; Peatlands; Protist distribution; Rainforest; Testate amoebae; Tropics.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Amoebozoa / classification*
  • Amoebozoa / cytology
  • Ecosystem*
  • Microscopy, Phase-Contrast
  • Peru
  • Species Specificity
  • Tropical Climate