Description of Trachelocorythion
provided by BioPedia
Test clear, compressed, in lateral view lenticular, aperture at the end of a short collar, dorsal lip slightly longer than the ventral one. The shell is composed of oval siliceous platelets while the apertural collar is covered with much smaller but not denticulated (cf. Sphenoderia) scales. Vesicular nucleus. Ecology: sphagnum mosses, acid skeletal soils. This genus has been erected to accommodate Corythion pulchellum which is quite different to other species in the genus Corythion. Type species: Trachelocorythion pulchellum (Penard, 1890). T. pulchellum is size polymorphic. Dimensions of the normal small morph: length 20 - 35 µm, the larger morph is 47 -61 µm long