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Sarcocysts of an unidentified species of Sarcocystis in the sea otter (Enhydra lutris)

J. P. Dubey·D. S. Lindsay·B.M. Rosenthal·N. J. Thomas
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Abstract

The number of Sarcocystis species that infect sea otters ( Enhydra lutris ) is unknown. Sea otter tissues were recently shown to harbor sarcocysts of S. neurona and of unidentified species of Sarcocystis . Whereas sarcocysts of S. neurona have walls 1–3 μm thick with type 9 villar protrusions, ultrastructure of a distinct thin-walled sarcocyst (0.5–0.7 μm thick) lacking villar protrusions, but instead exhibiting minute type 1 undulations on the sarcocyst wall, is described in this report. Parasites characterized from a sea otter infection were inferred to be related to, but distinct from, other species belonging to Sarcocystis , based on sequencing and phylogenetic analysis of a portion of the beta subunit of the plastid-encoded RNA polymerase gene.

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J. P. Dubey, D. S. Lindsay, B.M. Rosenthal, N. J. Thomas. 2003. Sarcocysts of an unidentified species of Sarcocystis in the sea otter (Enhydra lutris). https://doi.org/10.1645/0022-3395(2003)089%5B0397%3Asoauso%5D2.0.co%3B2

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