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Gregarines Infecting Ischnura spp. in Louisiana, U.S.A., Including Description of Geneiorhynchus gradalis n. sp. (Apicomplexa: Actinocephalidae: Actinocephalinae) from Ischnura ramburii (Odonata: Zygoptera) in St. John the Baptist Parish, Louisiana, U.S.A.

Smith-Herron, Autumn J., Cook, Tamara J.
Comparative parasitology 2018 v.85 no.1 pp. 42-47
Ischnura, Miozoa, adults, gregarines, morphometry, new species, oocysts, Louisiana
Geneiorhynchus gradalis n. sp. (Apicomplexa: Eugregarinida: Actinocephalidae: Actinocephalinae) is described from adults of Ischnura ramburii (Odonata: Zygoptera: Coenagrionidae). Geneiorhynchus gradalis is placed generically by way of its hesperidiform oocysts being released via simple rupture, by the fact that the epimerite is hemispherical and bears many semifalciform spines, and because association occurs late, just prior to syzygy. This species is distinguished from other members of the genus by its distinct oocyst morphometrics (narrowly hesperidiform with distinct bipolar truncations) and by the fact that its epimerite is shallowly toroid, bearing a single anterior row of semifalciform spines and becoming filamentous in mature forms with an absent tumidus. Its diamerite is meager. Herein we describe the new taxon while providing new host and locality records for known actinocephalid gregarines in Louisiana.