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<oai_dc:dc xmlns:dc="http://purl.org/dc/elements/1.1/" xmlns:oai_dc="http://www.openarchives.org/OAI/2.0/oai_dc/" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xsi:schemaLocation="http://www.openarchives.org/OAI/2.0/oai_dc/ http://www.openarchives.org/OAI/2.0/oai_dc.xsd">
  <dc:contributor>Eric M. Leis</dc:contributor>
  <dc:contributor>J.C. Richard</dc:contributor>
  <dc:contributor>I.F. Standish</dc:contributor>
  <dc:contributor>Jamie Bojko</dc:contributor>
  <dc:contributor>Jesse Weinzinger</dc:contributor>
  <dc:contributor>Diane L. Waller</dc:contributor>
  <dc:creator>Susan Knowles</dc:creator>
  <dc:date>2024</dc:date>
  <dc:description>&lt;div class="html-p"&gt;During an epidemiological survey following a mortality event of freshwater mussels in 2018 in the Embarrass River, Wisconsin, USA, we identified a novel microsporidian parasite in the ovaries of mucket (&lt;span class="html-italic"&gt;Actinonaias ligamentina&lt;/span&gt;), plain pocketbook (&lt;span class="html-italic"&gt;Lampsilis cardium&lt;/span&gt;), and fatmucket (&lt;span class="html-italic"&gt;Lampsilis siliquoidea&lt;/span&gt;) (Unionidae). Histopathology showed round-to-oval microsporidian spores in the cytoplasm of oocytes in 60% (3/5) of female mucket, 100% (4/4) of female plain pocketbook, and 50% (1/2) of female fatmucket. Using transmission electron microscopy, we found that mature spores were round-to-oval and measured 4.13 ± 0.64 µm (3.14–5.31) long by 2.88 ± 0.37 µm (2.36–3.68) wide. The spores had a thin electron-dense exospore with a spiky “hairy” coat, a thick electron lucent endospore, diplokaryotic nuclei, a polar vacuole, and 27–28 polar filaments arranged in 1–3 rows. Sequencing of the small subunit rRNA produced a 1356 bp sequence most similar to that of&lt;span&gt;&amp;nbsp;&lt;/span&gt;&lt;span class="html-italic"&gt;Pseudonosema cristatellae&lt;/span&gt;&lt;span&gt;&amp;nbsp;&lt;/span&gt;(92%), and phylogenetic analysis grouped it within the freshwater Neopereziida. Genetic, morphological, and ultrastructural characteristics did not closely match those of other&lt;span&gt;&amp;nbsp;&lt;/span&gt;&lt;span class="html-italic"&gt;Pseudonosema&lt;/span&gt;&lt;span&gt;&amp;nbsp;&lt;/span&gt;spp., and a new genus and species,&lt;span&gt;&amp;nbsp;&lt;/span&gt;&lt;span class="html-italic"&gt;Hirsutonosema embarrassi&lt;/span&gt;&lt;span&gt;&amp;nbsp;&lt;/span&gt;n. gen. n. sp., were designated. Additional studies could evaluate host susceptibility, distribution, seasonality, transmission, and lethal or sub-lethal effects of this parasite on freshwater mussels.&lt;/div&gt;</dc:description>
  <dc:format>application/pdf</dc:format>
  <dc:identifier>10.3390/parasitologia4020016</dc:identifier>
  <dc:language>en</dc:language>
  <dc:publisher>MDPI</dc:publisher>
  <dc:title>Hirsutonosema embarrassi n. gen. n. sp. (Phylum Microsporidia) in the Ovary of Mucket (Actinonaias ligamentina), Plain Pocketbook (Lampsilis cardium), and Fatmucket (Lampsilis siliquoidea) (Unionidae) from the Embarrass River, Wisconsin, USA</dc:title>
  <dc:type>article</dc:type>
</oai_dc:dc>