Summary: | Sparganosis is a neglected zoonotic parasitic disease that poses huge threats to humans worldwide. Snakes play an important role in sparganosis transmission because they are the most common second intermediate hosts for <i>Spirometra</i> parasites. However, the population genetics of <i>Spirometra</i> isolates from snakes is currently not well studied in China. The present study was performed to explore the molecular characteristics and phylogenetic analysis of <i>Spirometra</i> tapeworms from different species of snakes in Hunan Province. This study obtained 49 <i>Spirometra</i> isolates from 15 geographical areas in Hunan Province, Central China. Subsequently, the 18S and 28S ribosomal DNA (rDNA) fragments were amplified from the isolated parasites, and their sequences were analyzed to assess their genetic diversity. Phylogenetic analyses were performed using the maximum likelihood algorithm. The results showed that sequence variations among these isolates were 0–2.3% and 0–0.1% for 18S and 28S rDNA, respectively. The phylogenetic analysis showed that all <i>Spirometra</i> isolates from Hunan Province were clustered into the same branch with <i>Spirometra erinaceieuropaei</i> isolated from other areas (China, Vietnam, Australia). Moreover, the phylogenetic trees revealed that <i>Spirometra</i> is closely related to <i>Adenocephalus</i>, <i>Pyramicocephalus</i>, <i>Ligula</i>, <i>Dibothriocephalus</i>, <i>Schistocephalus</i>, and <i>Diphyllobothrium</i>. The <i>Spirometra</i> isolates of different hosts/regions in Hunan Province are not host segregated or geographically isolated, and support for the taxonomic status of <i>Spirometra</i> tapeworms in China has been added. These results provide reference values for future accurate identification and taxonomic status of <i>Spirometra</i> tapeworms in China.
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