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Genus Conicocassis

Two-component shell comprised of an ovoid to subspherical main body and a relatively very large conical to funnel-like and asymmetrically positioned flange extending out from a small circular aperture. The lower shell body of Conicocassis is ovoid or subspherical to spherical with a wall composed of polymorphous mineral particles within an organic matrix. The colorless to brown main shell body is topped by a cone-like flange, which extends out from a small circular aperture. The cone-like flange is mostly embossed with broken, or intact, diatoms frustules and quartz particles, and appears to be nearly as large as the main shell body if observed from the apertural view. In some cases, the flange may be characterized by coloration distinct from the main shell body. The attachment area of the apertural flange to the main shell body produces a pronounced constriction in the shell wall that is particularly diagnostic (Nasser, Patterson, 2015). Ecology: freshwater, wet moss. Type species: Conicocassis pontigulasiformis (Beyens et Chardez, 1986).