A New Mayorella Species Isolated from the Mariana Trench Area (Pacific Ocean)

In this paper, we describe a new naked amoeba species, Mayorella marianaensis sp. n., order Der-mamoebida, isolated from the bottom of the Pacific Ocean (>3,000 m depth) in the vicinity of the Mar-iana Trench, based on morphological and molecular data. The newly discovered species was identified based on morphological and molecular data. This is the first time that a Mayorella species was discovered in the deep sea (>1,000 m). Mayorella marianaensis is an irregularly rectangular naked amoeba (30-120 x 11-60 mm), with a narrow frontal hyaline area. Four to 15 conical sub-pseudopodia, and three kinds of floating forms are identified. Trophozoites have a thick cell coat consisting of two distinct layers. The small subunit ribosomal RNA gene phylogeny showed that M. marianaensis is classified into Dermamoebida, and is a sister clade to other Mayorella species whose sequences are available. BLAST analysis revealed that M. marianaensis is most similar to Coronamoeba vil-lafranca and Mayorella sp. JJP-2003, with sequence identities of 92.43% and 88.30%, respectively.(c) 2023 The Author(s). Published by Elsevier GmbH. This is an open access article under the CC BY-NC-ND license (http://creativecommons.org/licenses/by-nc-nd/4.0/).

Automated summary

In this study, a new species of naked amoeba, Mayorella marianaensis sp. n., was described. It was isolated from the deep ocean (>3,000 m depth) near the Mariana Trench, and identified based on morphological and molecular data. Mayorella marianaensis is an irregularly rectangular naked amoeba with a narrow frontal hyaline area, distinctive sub-pseudopodia, and three forms of floating forms. Phylogenetic analysis revealed its classification into Dermamoebida and its relationship with other Mayorella species. BLAST analysis showed its closest similarities to Coronamoeba villafranca and Mayorella sp. JJP-2003.