The Thorny-headed Worms (Acanthocephala) also commonly known as Spiny-headed Worms, is a biological phylum of the domain Eukarya and kingdom Animalia.
Archiacanthocephala
Eoacanthocephala
Palaeacanthocephala
Polyacanthocephala
Annelida
Arthropoda
Brachiopoda
Bryozoa
Chaetognatha
Chordata
Cnidaria
Ctenophora
Echinodermata
Platyhelminthes
Gastrotricha
Gnathostomulida
Nematomorpha
Hemichordata
Phoronida
Kamptozoa
Kinorhyncha
Loricifera
Micrognathozoa
Mollusca
Nematoda
Onychophora
Orthonectida
Placozoa
Priapulida
Nemertea
Rhombozoa
Rotifera
Sipuncula
Porifera
Tardigrada
Acanthocephala
Xenacoelomorpha