Sarcocystis pinnipedi predominates Sarcocystis spp. infections in free-ranging Alaskan marine mammals

The diversity of Sarcocystis spp. infecting Alaskan marine mammals is largely unknown, which is relevant in a region of the world where hunting and consumption of marine mammals is essential to Alaskan native food security. Intramuscular sarcocysts were identified by histology during assessment of subsistence-hunted Alaskan pinnipeds, cetaceans, and ursids. Multilocus (ITS1, cox1, 18S, and rpoB) genetic characterization and phylogeny identified 51.2% of Sarcocystis spp. as identical to the newly described Sarcocystis pinnipedi. Infections with Sarcocystis canis (4.8%) and three novel Sarcocystis clades made up a minority of infections. Identification of potentially new species provides the framework for future investigation.