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Porosia bigibbosa
Porosia bigibbosa
P. bigibbosa with arrowed pores

Genus Porosia (Jung, 1942) emend. Bobrov et Kosakyan, 2015

Diagnosis: Test pyriform, with a rounded posterior end, laterally compressed. In front view two distinct lateral depressions with two large invaginated pores are situated on each side, which are connected by internal tubes as in the genus Certesella. In profile, small lateral pores can be observed, just anterior to the large pores. The lateral keel can (or can not) be present surrounding 1/3 of the posterior lateral margin. Test composed of euglyphid shell plates embedded in unstructured cement. Aperture curved, surrounded by an organic lip.

Type species: Porosia bigibbosa (Penard) Jung, 1942.

Ecology: herbivorous and carnivorous? Habitat: sphagnum mosses, litter, soil, rare genus. Rare.

Remarks: The keel is an important distinctive character between Porosia species:
Porosia bigibbosa – lacking of a lateral keel,
Porosia paracarinata – presence of a lateral keel.
This genus is closely related to Certesella but lacks the punctuated neck.

References: Bobrov, A. and Kosakyan, A., 2015. A New Species from Mountain Forest Soils in Japan: Porosia paracarinata sp. nov., and Taxonomic Concept of the Genus Porosia Jung, 1942. Acta Protozool. 54: 289–294.

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