Quadrulella variabilis Kosakyan, Lahr, Mulot, Meisterfeld, Mitchell & Lara, 2016, sp. nov.

Quadrulella variabilis sp. nov. Kosakyan, Lahr, Mulot, Meisterfeld, Mitchell and Lara

Description. Test ovoid or pyriform, with a rounded posterior end, laterally compressed towards the pseudostome, very similar to that in Q. symmetrica, sometimes with an elongated neck. Test colourless, composed of square plates, regularly arranged in rows. The plates are smaller near the aperture (3 – 4 µm), then gradually become larger (up to 7 – 9 µm) toward the posterior end of the test. Dimensions of the test (based on the seven sequenced individuals): length = 66 – 69 (96) µm, breadth = 35 – 40.5 (45) µm. Aperture 17 – 18.5 µm wide, often curved and bordered by a thin organic lip.

Differential diagnosis. See diagnosis of Q. symmetrica.

Type locality. The tests were collected from Sphagnum mosses in Le Cachot bog, Vallée de la Brévine, Canton of Neuchâtel, Switzerland (47.5 ° N, 6.4 ° E).

Holotype. Fig. 2, paratype Fig. 7 d.

Etymology. The species has members with a variable neck length.

Notes. One other possibility is to describe the entire clade as Q. longicollis. However, given that we have only one Q. longicollis sequence (which may not correspond to the typical Q. longicollis, see Discussion), DNA of which was extracted from more than one cell, we would need additional data to understand whether the elongated neck is a result of phenotypic plasticity or a genetically fixed character.