Pentazonia

Life-forms

Superregnum: Eukaryota
Cladus: Unikonta
Cladus: Opisthokonta
Cladus: Holozoa
Regnum: Animalia
Subregnum: Eumetazoa
Cladus: Bilateria
Cladus: Nephrozoa
Cladus: Protostomia
Cladus: Ecdysozoa
Cladus: Panarthropoda
Phylum: Arthropoda
Subphylum: Myriapoda
Classis: Diplopoda
Subclassis: Chilognatha
Infraclassis: Pentazonia
Superordines: Limacomorpha - Oniscomorpha
[list of superordines after Shelley (2003)]
References

Shelley, R.M. 2003: A revised, annotated, family-level classification of the Diplopoda. Arthropoda selecta, 11 (3): 187–207.

Pentazonia is a taxonomic infraclass of millipedes containing the pill-millipedes (Oniscomorpha) which can roll into a ball and the order Glomeridesmida which cannot. Defining traits (apomorphies) include divided sternites, a labrum with single median tooth, and an enlarged pygidium on the hind-most body segment.[1] Pentazonia is in the dominant millipede subclass Chilognatha which have a calcified exoskeleton and modified sperm-transferring legs in males. In contrast to the Helminthomorpha – the other Chilognathan infraclass, the sperm-transferring legs are located on posterior body segments and known as telopods. Pentazonians are relatively short-bodied, with between 13 and 21 body segments.[2] The Pentazonia contains one extinct order, Amynilyspedida, often referred to the Oniscomorpha.[3]
References

"Putative apomorphies of millipede clades" (PDF). Milli-PEET: Millipede Systematics. The Field Museum, Chicago, IL. 26 September 2006. Retrieved 5 December 2013.
Enghoff, Henrik (1990). "The Ground Plan of Chilognathan Millipedes (External Morphology)". In Minelli, Alessandro (ed.). Proceedings of the 7th International Congress of Myriapodology. Leiden, the Netherlands: E.J. Brill. pp. 1–22. ISBN 9789004089723.
Hannibal, Joseph T; Feldmann, Rodney M. (1981). "Systematics and Functional Morphology of Oniscomorph Millipedes (Arthropoda: Diplopoda) from the Carboniferous of North America". Journal of Paleontology. 55 (4): 730–746.