Pentazonia | |
---|---|
Glomeris marginata, female | |
Scientific classification | |
Domain: | Eukaryota |
Kingdom: | Animalia |
Phylum: | Arthropoda |
Subphylum: | Myriapoda |
Class: | Diplopoda |
Subclass: | Chilognatha |
Infraclass: | Pentazonia Brandt, 1833 |
Superorders | |
Synonyms | |
Opisthandria Verhoeff, 1894 |
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]