Franzenella
(tree size 3)
Arachnidium
(tree size 10)
Arachnidium (bryozoan)
Arachnoidella
(tree size 12)
Arachnoidea
(tree size 8)
Arachnoidea (bryozoan)
Parachnoidea
(tree size 2)
Cryptoarachnidium
(tree size 1)
Pierrella
(tree size 2)
Arachnidia
Cardoarachnidium
Simplicidium