A New Species of Myxobolus (Cnidaria: Myxosporea: Myxobolidae) from the Soft Dorsal Fin of the Green Sunfish, Lepomis cyanellus (Centrarchiformes: Centrarchidae), from the Caddo River of Western Arkansas, USA

The green sunfish, Lepomis cyanellus, is a common centrarchid that has been previously reported to harbor several myxosporeans. In May 2022, six L. cyanellus were collected from the Caddo River, Montgomery County, Arkansas, USA, and had their gills, gall bladders, urinary bladders, fins, integument, other major organs, and musculature examined for myxosporeans. A single individual was found to harbor a new species of Myxobolus infecting the soft dorsal fin. A qualitative and quantitative morphological description was based on fresh plasmodia and myxospores. Elliptoid to obovoid myxospores of Myxobolus picassoi sp. n. are asymmetrical, 12.2 µm long × 9.1 µm wide, with two broadly pyriform to broadly ovoid subequal polar capsules. Molecular data consisted of a 2042 base pair sequence of the partial small subunit rRNA gene (SSU). Phylogenetic analysis revealed that M. picassoi sp. n. is a member of a clade of myxosporean species that predominately infect centrarchid sunfishes from North America. This is the fifth report of a Myxobolus from L. cyanellus, but the first report of a species infecting the soft dorsal fin. This article was registered in the Official Register of Zoological Nomenclature (ZooBank) as urn:lsid:zoobank.org:pub:146D21D1-E416-41C7-A1F6-8AB2AC6D9260.