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Biota (Life)
Eukaryote (Eukarya)
Chromista
Harosa
Halvaria
Alveolate (Alveolata)
Ciliophora (Ciliates)
Spirotrichea (Spirotrich)
Oligotrich (Oligotrichia)

Oligotrichida (23196607)

Children (4 direct children, 133 direct and indirect children):

Strombidiidae (tree size 106)

Cyrtostrombidiidae (tree size 4)

Pelagostrombidiidae (tree size 2)

Tontoniidae (tree size 17)