Meisterfeldia polygonia, Bobrov, 2016

Bobrov, Anatoly, 2016, Description of a New Testate Amoebae Genus Meisterfeldia with Notes on the Systematics of the Suborder Phryganellina (Amebozoa; Tubulinea; Arcellinida), Acta Protozoologica 55 (4), pp. 211-219 : 215-217

Meisterfeldia polygonia sp. nov.

Description: Shell is very small, bilaterally symmetrical, narrowly ovate, slightly compressed, almost circular in a transverse section, brown, non-transparent. Dorsal side weakly convex, posterior end evenly curved, anterior end with aperture slightly cut obliquely towards ventral side. Aperture elliptical, subterminal. Shell surface smooth, without mineral inclusions ( Figs 6 , 7 ).

Measurements ( Table 1): shell length 6.75–7.50 µm; shell breadth 3.75–4.50 µm; shell depth 3.75–4.00 µm; axis of aperture 2.50–3.00 µm.

List of associated testate amoebae: The species was found in associations with the following species (occurrence, %): Cryptodifflugia oviformis f. fusca (26.70); Trinema lineare (10.86); Centropyxis sylvatica (9.50); Trinema complanatum v. platystoma (8.60); Centropyxis aerophila (4.52); Cryptodifflugia bassini (4.07); Wailesella eboracensis (4.07); W. sp. (4.07); Trimena complanatum (3.62); Schoenbornia humicola (3.17); Euglypha laevis (3.17); E. cristata (2.71); Heleopera petricola v. amethystea (1.36); Assulina muscorum (1.36); Meisterfeldia chibisovi sp. nov. (0.91); Nebela tincta (1.36); N. militaris (0.90); Centropyxis constricta (0.90); Cyclopyxis eurystoma (0.90); Meisterfeldia wegeneri sp. nov. (0.90); Bullinularia gracilis (0.45); Heleopera rosea (0.45); Hyalosphenia minuta (0.45); H. subflava (0.45); Argynnia dentistoma (0.45); N. parvula (0.45); Valkanovia elegans (0.45); Corythion dubium v. minima (0.45); Cryptodifflugia minuta (0.45); Archerella flavum (0.45); Meisterfeldia polygonia sp. nov. (0.45); Meisterfeldia vanhoornei comb. nov. (0.45); Euglypha filifera v. magna (0.45); Centropyxis cf. aculeata (0.45).

Type locality: Polygonal tundra, 28 km northwestward of Chokurdakh settlement (Yakutia). 70°49′55.4″N 147°28′39.1″E. Biotope: Sphagnum , peat tussock, microelevation in the center of the testing area. Vegetation: Carex chordorrhiza, Andromeda polifolia, Salix myrtilloides , Ledum decumbens , Carex stans, Polytrichum commune, Sphagnum sp. Soil – Sphagnic Fibristel ( US ST).

Type specimen: Laboratory of Soil Bioindication, Department of Soil Geography, Faculty of Soil Science , Lomonosov Moscow State University , slide No. 3-2015 .

Etymology: The species was named after the abbreviation of the Joint German-Russian DFG – RFBR (Russian Foundation for Basic Research) Research Project “Polygons in tundra wetlands: dynamics and response to climate variability in Polar Regions (POLYGON)”. The field and laboratory protozoological studies were carried out within the framework of the latter project.

Related species – similarities and differences: The species differs morphologically from Cryptodifflugia vanhoornei by its smaller size: the shell is nearly twice smaller, it is more graceful and always stained with brown.

Figures

Fig. 6. Light microscopical image of Meisterfeldia polygonia in lateral view.A – typical specimen, B – morphological variability.

Fig. 7. Outline of Meisterfeldia polygonia: lateral (left) and ventral (right) views. 1–4 – characters of the test measured. Scale bar: 5 µm.