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Matsakision cassagnaui
Matsakision – after Bonnet, 1967

Matsakision   Bonnet, 1967

Diagnosis: Shell hyaline, elongated ovoid, very little compressed, truncated perpendicularly or very slightly obliquely in the region of the pseudostome. Pseudostome acrostome or very slightly plagiostome, sub-circular, with a slight neck, which can sometimes be barely noticeable. Shell covered with elliptical scales, sub-circular near the pseudostome, without very clear orientation, not overlapping, although sometimes they may be contiguous, and embedded in a light yellow hyaline cement.
Type species: Matsakision cassagnaui Bonnet, 1967

Type location: Vityna Pass, Peloponnese, Greech. At 1000 m altitude, in sloping fir forest; powdery soil brought in by wind, at the base of mosses and of the fern Asplenium adiantum-nigrum, on limestone rock in the undergrowth.

Remarks: Bonnet (1967) did not observe living cells, but based on the general constitution of the shell he believed that this genus belonged to the Filosea. Matsakision can be distinguished from:
Corythion, by its extremely weak plagiostomy and by the pseudostome in the neck without invagination.
Cyphoderia, by the elliptical shape of the scales and by their completely different arrangement.
Cyphoderiopsis, by the fact that, in this last genus, the scales are circular and of variable size.

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