Jackson Estuarine Laboratory

Uronychia transfuga (O.F. Müller, 1786) Stein, 1859 (Ciliophora, Hypotrichida, Uronychiidae): Cortical structure and morphogenesis during division


Morphogenesis of cell division was investigated in Uronychia transfuga utilizing both light microscopy of living and stained specimens and SEM of preserved specimens. The cortical morphogenetic pattern of Uronychia is similar in several respects to that of the members of the family Euplotidae. These features include: the de novo development of the opisthe oral primordium in a subcortical pouch; the development of frontoventral and transverse cirri for both the proter and opisthe from 5 cirral primordia that form de novo within a single latitudinal developmental zone; and the absence of right marginal cirri. The members of the genus Uronychia also show a number of unique characteristics: development of a proter oral primordium that causes partial replacement of the parental adoral zone of oral polykinetids during development of the proter; a large oral membrane that is divided into a right and left component; large caudal cirri that bend to the left; and dorsal kineties comprised of closely set paired‐kinetosome kinetids. When compared to the other euplotid‐like ciliates, these unique features support the placement of the genus Uronychia in a separate family, Uronychiidae.

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Journal Title

Journal of Protozoology



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