AUTHOR=Yoo Jiae , Kim Sunju , Coats D. Wayne 

TITLE=Morphology of Hobagella saltata n. gen. and n. sp. (Syndiniophyceae, Miozoa) infecting the marine dinoflagellate Cucumeridinium coeruleum (Dinophyceae, Miozoa) and its potential onshore advection

JOURNAL=Frontiers in Marine Science

VOLUME=10

YEAR=2024

URL=https://www.frontiersin.org/journals/marine-science/articles/10.3389/fmars.2023.1296836

DOI=10.3389/fmars.2023.1296836

ISSN=2296-7745

ABSTRACT=<p>Over the past decade, molecular phylogenies have placed endoparasites of the genus <italic>Euduboscquella</italic> in a distinct subclade within clade 4 of the Marine Alveolate (MALV) Group I. Recently, however, rRNA gene sequences have become available for four novel <italic>Euduboscquella</italic>-like species that infect dinoflagellates, with phylogenies including these sequences indicating that the genus <italic>Euduboscquella</italic> is paraphyletic. Here, we provide a morphological characterization of the intracellular and extracellular life-cycle stages of a novel species that infects <italic>Cucumeridinium coeruleum</italic>, a warm water pelagic species sometimes found in coastal environments. We formally describe the novel parasite, <italic>Hobagella saltata</italic> n. gen, n. sp., and identify a constellation of morphological and developmental characters that distinguish it, as well as <italic>Euduboscquella melo</italic> and <italic>E. nucleocola</italic>, both parasites of dinoflagellates, from <italic>Euduboscquella</italic> species that infect ciliates. We recommend the reassignment of <italic>E</italic>. <italic>melo</italic> and <italic>E. nucleocola</italic> as <italic>Hobagella melo</italic> n. comb. and <italic>H. nucleocola</italic> n. comb., respectively. We also propose the family Hobagellidae for these three congeners. We anticipate that the character set developed for distinguishing species of <italic>Euduboscquella</italic> and <italic>Hobagella</italic> will be valuable for sorting other <italic>Euduboscquella</italic>-<italic>Hobagella</italic>-like taxa scattered across the Group I phylogeny and will provide insight into morphological evolutionary patterns within Group I. Lastly, we consider the potential influence of summer-fall typhoons on the occurrence of <italic>H. saltata</italic> and its host <italic>C. coeruleum</italic> in near-shore waters along the southeastern coast of Korea and propose a hypothesis regarding the northward transport and onshore advection of host and parasite populations. If future research supports the hypothesized mechanisms, it could help us better understand parasite distribution and potential changes in biogeography associated with ongoing global changes in surface seawater temperature.</p>