metopus filum metopus filum metopus filum is a species of metopid first found in soil from the murray river floodplain, australia. it can be distinguished from its congeners by its thin body, an absence of cortical granules, and a low number of ciliary rows and adoral polykinetids. metopus filum scientific classification domain: eukaryota (unranked): sar (unranked): alveolata phylum: ciliophora subphylum: intramacronucleata order: armophorida family: metopidae genus: metopus species: m. filum binomial name metopus filumvďačný & foissner, 2016