Complete mitochondrial genomes of June sucker and Utah sucker ( and ).

The relationship between June sucker (, Jordan, 1878) and Utah sucker (, Jordan & Gilbert, 1881) has been a matter of controversy since the mid 1900s. is endemic to Utah Lake, UT and has a subterminal mouth adapted for pelagic feeding. is widely distributed throughout the Bonneville Basin and Upper Snake River Basin and has a ventral mouth adapted for benthic feeding. has been recognized as a separate ancient genus. Despite being morphologically distinct, no study has successfully identified residual genetic markers that separate these species. Of these studies, several have used a subset of mitochondrial genes, but no study has analyzed the complete mitochondrial genomes (mitogenomes) of these suckers (Pisces: Catostomidae). To further explore the genetic relationships between these species, we report the complete mitogenomes of and . DNA was sequenced using an Illumina HiSeq 2500 system and mitogenomes were assembled and annotated using Geneious v. 2021.2 and MitoAnnotator, respectively. The mitogenomes of and are both 16,623 bp and are ∼0.072% divergent. We examine the phylogenetic relationship between and using 33 mitogenomes, representing 16 species, from Catostomidae. Our data suggest that is sister to . Additional samples from multiple localities and/or cohorts of these species will allow us to better resolve the complicated phylogenetic relationships between these species.