Kingdom [Animalia] Linnaeus, 1758 - animals Subkingdom Protozoa Goldfuss, 1818 see Kingdom Protozoa Goldfuss, 1818 Class Ciliata see [unranked] ciliates Order Spirotricha Suborder Heterotricha Stein, 1859 Genus [Spirostomum] Ehrenberg, 1834 1 Spirostomum ambiguum (Müller, 1786) Ehrenberg, [1834]