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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)
Chelicerata (Chelicerates)
Euchelicerata
Prosomapoda
Merostomata (Horseshoe crabs)

Chasmataspidida (1068066)

Children (2 direct children, 18 direct and indirect children):

Diploaspididae (tree size 14)

Chasmataspididae (tree size 2)