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Centropyxis pontigulasiformis
C. pontigulasiformis – Photomicrograph Louis Beyens

Conicocassis pontigulasiformis (Beyens et al., 1986) Nasser and Anderson, 2015
Basionym: Centropyxis pontigulasiformis Beyens, Chardez and De Bock, 1986

Diagnosis:  Shell formed of two distinct parts: a perfectly spherical chamber and a large semi-circular visor. The chamber has a small circular aperture. The shell wall is composed of an organic matrix, incorporating fine plate-like polymorphous mineral particles. The visor which expands fan-like above and around the aperture, is mostly embossed with more voluminous quartz particles, in particular at the rim. Seen from an apertural view, this visor is as large as the shell body.

Dimensions: Beyens et al.: diameter of the shell 58-62 µm, length of the visor 24-28 µm (n=5); diam. of aperture 8-10 µm; total length 82-90 µm

Ecology: mosses and Sphagnum. Canadian and European (Svalbard) arctic, Northern Sweden (Chardez, 1990); My records: the Netherlands (‘t Hol, 1980, Laegieskamp, 2013), Germany (Rotes Wasser, 2017) and Austria (Tirol, Angie Opitz, pers. comm.).

References: Nasser, N.A., Patterson, T. (2015). Conicocassis, a new genus of Arcellinina (testate lobose amoebae). Palaeontologia Electronica 18.3.46A: 1-11.
palaeo-electronica.org/content/2015/1323-new-genus-of-arcellinia.

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