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
Echinothurioida
Echinothuriidae (Echinothurioida)
Hygrosomatinae
Children (3 direct children, 3 direct and indirect children):
Hygrosoma luculentum
Hygrosoma hoplacantha
Hygrosoma petersii