Breviata anathema is a single-celled protist. It lacks mitochondria but has numerous differences with other amitochondiate Amoebozoa like Entamoeba and Endolimax. Because B. anathema has genes which are known from mitochondria, it is likely to possess degenerate mitrochondria. The closest relatives of B. anathema are not clear; molecular data places it in the Amoebozoa, but without obvious affinity to known groups of Amoebozoa.
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