world of amoeboid organisms

Velamentofex tyrolensis (photomicrograph Steffen Clauß)

Family Velamentofexidae Völcker and Clauß, 2020

Diagnosis: Multinucleate organic-walled monothalamous foraminifera. Test spherical to pyriform, usually surrounded by a broad layer of mucus-like material not easily observable as it is covered with food particles, digestion residues and detritus. Test wall flexible, colorless and smooth, varying in thickness. Aperture terminal, oblique. Peduncle more or less trumpet-shaped, eccentrically located and varying in length, surrounded by a hyaline peduncular sheath. Radiating network of granuloreticulopodia can be very large, extending some millimeters over the substrate. Nuclei ovular, numerous. Cytoplasm with many contractile vacuoles in the periphery of the cell and numerous small crystalline inclusions, consisting of a refractive more or less rod-shaped yellowish body, attached to a spherical non-refractive body.

Molecular features: The partial SSU rDNA sequences contain between 1159–1166 nucleotides, the GC content ranges from 35.8% to 37.6%. Pairwise distances range from0.015 to 0.025, the overall average is 0.036.

Type genus: Velamentofex Völcker and Clauß, 2020

Genera assigned: Velamentofex. 

Genus Velamentofex Völcker and Clauß, 2020

Diagnosis: As for family.

Type species: Velamentofex berolinensis  Völcker and Clauß, 2020

Species assigned: V. berolinensis, V. saxonensis, V. tyrolensis.

V. saxonensis (photomicrograph Steffen Clauß)

Literature: Siemensma, F., Holzmann, M., Apothéloz-Perret-Gentil, Laure, Clauß, S., Voelcker, E., Bettighofer, W., Khanipour Roshan, S., Walden, S., Dumack, K., Pawlowski, J., 2020. Broad sampling of monothalamids (Rhizaria, Foraminifera) gives further insight into diversity of non-marine Foraminifera. Eur. J. Protistol. https://doi.org/10.1016/j.ejop.2020.125744

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