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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)
Ecdysozoa (Ecdysozoan)
Panarthropoda
Tactopoda
Arthropoda (Arthropod)
Mandibulata
Tracheata
Uniramia
Pancrustacea
Hexapoda (Hexapods)
Insect (Insects)
Dicondylia
Pterygota (Pterygote)
Ephemeroptera (The mayflies)
Pisciforma

Heptagenioidea (3133322)

Children (4 direct children, 741 direct and indirect children):

Heptageniidae (tree size 666)
Flatheaded mayflies

Oligoneuriidae (tree size 68)
Brushleg mayflies

Arthropleidae (tree size 3)
Flatheaded mayflies

Pseudironidae
Crabwalker mayflies