A phylogenetic analysis of rare hemimastigotes — free-living, predatory protists — found that they actually form their own supra-kingdom, CBC reports.
Yana Eglit, a Dalhousie University graduate student, collected these hemimastigotes by happenstance while hiking — she often carries sample vials with her and she scooped up some soil to analyze not knowing what was there, the CBC adds. After adding water and waiting, she found that her sample contained some interesting microbes, including two new species of hemimastigotes, it notes. She and her colleagues named one Hemimastix kukwesjijk and say the other, belonging to the Spironema genus, is awaiting formal description, as they report in Nature.
They also performed a phylogenetic analysis of these samples based on their transcriptomes. This analysis placed Spironema and Hemimastix into a phylogenetically isolated clade at the base of Diaphoretickes, which the researchers say suggests Hemimastigophora represent a novel, supra-kingdom-level lineage.
"They represent a major branch… that we didn't know we were missing," co-author Alastair Simpson, Eglit's supervisor at Dalhousie tells the CBC. "There's nothing we know that's closely related to them." He adds that they estimate that it has been about a billion years since a common ancestor of both hemimastigotes and another organism was alive.