Allomalorhagida
Allomalorhagida is a class of worms belonging to the phylum Kinorhyncha. The class historically had no orders, and was only divided into families. Recently, Pycnophidae has been found to be sister to the order Anomoirhaga, comprising the other four families. Families
Allomalorhagida consists of the following families:

 Pycnophyidae
 Order Anomoirhaga
 Cateriidae
 Dracoderidae
 Franciscideridae
 Neocentrophyidae

References 

Kinorhyncha
Protostome classes