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Biota (Life)
Eukaryote (Eukarya)
Podiata
Unikont (Unikonta)
Opisthokont (Opisthokonta)
Holozoa
Filozoa
Apoikozoa (Choanozoa)
Animal (Animalia)
Metazoa
Epitheliozoa
Eumetazoa
Bilateria
Deuterostome (Deuterostomia)
Echinodermata (Echinoderms)
Sea urchin (Echinoidea)
Euechinoidea
Irregularia
Atelostomata
Spatangoida
Brissidina
Spatangidea (Spatangoidea)
Macropneustidae

Phrissocystis (18607502)

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

Phrissocystis multispina

Phrissocystis aculeata