Foraminifera are unicellular eukaryotes characterized by the presence of granuloreticulopodia and the possession of a membranous, agglutinated, or calcareous test, which is either monothalamous (single-chambered) or polythalamous (multi-chambered) (Loeblich and Tappan 1987). Within monothalamids some species like Reticulomyxa ﬁlosa are amoeboid naked forms. Until 1859, foraminifera were only known from marine habitats, but that year Claparède and Lachmann described a monothalamid foraminifer, Lieberkuehnia wageneri, sampled from an unknown water body in Berlin. It had a smooth flexible test with an entosolenian tube that separated the main cytoplasm mass from the pseudopodial peduncle. In 1886 Henri Blanc, a Swiss scientist, described another freshwater foraminifer, Gromia brunneri, which he had collected from the bottom of Lake Geneva. This single-chambered species had an agglutinated test, an organic layer covered and/or embedded with foreign, mainly non-organic, particles. In subsequent years, Eugène Penard, another Swiss protozoologist, described four similar species Gromia gemma and G. squamosa (1899), G. linearis (1902) and G. saxicola (1905) from the same lake. He also described G. nigricans (1902), which he found not far from Lake Geneva in Mategnin and a marsh near Rouelbeau.