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Biota (Life)
Eukaryote (Eukarya)
Chromista
Harosa
Halvaria
Alveolate (Alveolata)
Ciliophora (Ciliates)
Postciliodesmatophora
Heterotrichea (Heterotrich)
Heterotrichida

Spirostomidae (18679421)

Children (3 direct children, 17 direct and indirect children):

Spirostomum (tree size 7)

Gruberia (tree size 5)

Propygocirrus (tree size 2)