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bioRxiv · 10.1101/2020.05.12.090621

Mediocremonas mediterraneus, a New Member within the Developea

Weiler, B. A.·Sa, E.·Sieracki, M. E.·Massana, R.·del Campo, J.
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Abstract

The Stramenopiles are a large and diverse group of eukaryotes that possess various lifestyles required to thrive in a broad array of environments. The stramenopiles branch with the alveolates, rhizarians, and telonemids, forming the supergroup TSAR. Here, we present a new genus and species of aquatic nanoflagellated stramenopile: Mediocremonas mediterraneus, a free-swimming heterotrophic predator. M. mediterraneus cell bodies measure between 2.0-4.0 m in length and 1.2-3.7 m in width, possessing two flagella and an oval body morphology. The growth and grazing rate of M. mediterraneus in batch cultures ranges from 0.68 to 1.83 d-1 and 1.99 to 5.38 bacteria h-1, respectively. M. mediterraneus was found to be 93.9% phylogenetically similar with Developayella elegans and 94.7% with Develorapax marinus, two members within the class Developea. The phylogenetic position of the Developea and the ability of M. mediterraneus to remain in culture makes it a good candidate for further genomic studies that could help us to better understand phagotropy in marine systems as well as the transition from heterotrophy to phototrophy within the stramenopiles.

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Weiler, B. A., Sa, E., Sieracki, M. E., Massana, R., del Campo, J.. 2020-05-13. Mediocremonas mediterraneus, a New Member within the Developea. https://doi.org/10.1101/2020.05.12.090621

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