Nebela Leidy 1874

Introduction

Fig. 1: Nebela tincta, a species with lateral pores (p) in the test. © Ralf Meisterfeld

The genus Nebela is dominant in mosses and humus-rich soils. Nebela species can be as small as 30 µm but can reach up to 380 µm (N. maxima).

Loeblich & Tappan (1964) have designated Nebela numata Leidy, 1874 as valid type species which unfortunately is a junior subjective synonym of Nebela collaris (Ehrenberg, 1848).

Characteristics

The test can be ovate, pyriform, elongate or with a long neck, but always compressed, sometimes with lateral pores (e.g., N. tincta, Fig. 1). Their colour is yellowish, transparent often with predated siliceous plates or diatom frustles in an unstructured organic cement. All species have an ovular nucleus. 

Discussion of Phylogenetic Relationships

The molecular data of Lara et al. (2008) suggest that the genus is probably paraphyletic. Taxa described as varieties may deserve the rank of species. This would increase the number of species significantly.

Ecology

Most Nebela spp. are predators of small Euglyphida. Habitat: common in mosses (Sphagnum) and soil. Additional ecological data: Bonnet (1990), Tolonen et al. (1992).

References

Deflandre, G. 1936. Etude monographique sur le genre Nebela Leidy (Rhizopoda - Testacea). Ann. Protistol., 5:201-286.

Jung, W. 1942b. Illustrierte Thekamöben-Bestimmungstabellen. I. Die Systematik der Nebelinen. Arch. Protistenk., 95:357-390.

Lara, E., Heger, T.J., Ekelund, F, Lamentowicz and Mitchell, E.A.D. 2008: Ribosomal RNA Genes challenge the monophyly of the Hyalospheniidae (Amoebozoa: Arcellinida). Protist 159: 165-176.

Ogden, C. G. & Hedley, R. H. 1980. An Atlas of Freshwater Testate Amoebae. Oxford University Press, Oxford.

Rauenbusch, K. 1987. Biologie und Feinstruktur (REM- Untersuchungen) terrestrischer Testaceen in Waldböden (Rhizopoda, Protozoa). Arch. Protistenk., 134:191-294.

Tolonen, K., Warner, B. G. & Vasander, H. 1992. Ecology of Testacea (Protozoa, Rhizopoda) in Mires in Southern Finland. 1. Autecology. Arch. Protistenk., 142:119-138.

Bonnet, L. 1990. Données écologiques sur quelques Hyalospheniidae et Paraquadrulidae (Thécamoebiens) des sols (Deuxième partie: genre Nebela). Bull. Soc. Hist. Nat. Toulouse, 126:9-17.