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Biota (Life)
Eukaryote (Eukarya)
Podiata
Unikont (Unikonta)
Opisthokont (Opisthokonta)
Holozoa
Filozoa
Apoikozoa (Choanozoa)
Animal (Animalia)
Metazoa
Epitheliozoa
Eumetazoa
Bilateria
Nephrozoa (Eubilateria)
Protostome (Protostomia)
Spiralia (Spiralians)
Lophotrochozoa
Annelida (Annelid)
Clitellata

Leech (43012)

Children (4 direct children, 322 direct and indirect children):

Euhirudinea (tree size 226)
True leeches

Gnathobdelliformes (tree size 92)

Hirudinida

Acanthobdellidea