Millipedes are a group of arthropods that are characterised by having two pairs of jointed legs on most body segments; they are known scientifically as the class Diplopoda, the name derived from this feature. Each double-legged segment is a result of two single segments fused together. Most millipedes have very elongated cylindrical or flattened bodies with more than 20 segments, while pill millipedes are shorter and can roll into a tight ball. Although the name "millipede" derives from Latin for "thousand feet", no species was known to have 1,000 or more until the discovery in 2020 of Eumillipes persephone, which can have over 1,300 legs. There are approximately 12,000 named species classified into 16 orders and around 140 families, making Diplopoda the largest class of myriapods, an arthropod group which also includes centipedes and other multi-legged creatures.
Ralph Vary Chamberlin was an American biologist, ethnographer, and historian from Salt Lake City, Utah. He was a faculty member of the University of Utah for over 25 years, where he helped establish the School of Medicine and served as its first dean, and later became head of the zoology department. He also taught at Brigham Young University and the University of Pennsylvania, and worked for over a decade at the Museum of Comparative Zoology at Harvard University, where he described species from around the world.
Glomerida is an order of pill-millipedes found primarily in the Northern Hemisphere. Also known as northern pill millipedes, they superficially resemble pill-bugs or woodlice, and can enroll into a protective ball. They have twelve body segments, 17 to 19 pairs of legs, and males have enlarged rear legs involved in mating. The order includes about 30 genera and at least 280 species, including Glomeris marginata, the common European pill-millipede. The order contains members in Europe, South-east Asia and the Americas from California to Guatemala. Although historically considered closely related with the similar sphaerotheriidans that also enroll, some DNA evidence suggest they may be more closely related to glomeridesmidans, a poorly known order that does not enroll.
Desmoxytes, whose species are commonly known as the dragon millipedes, is a genus of millipedes of the family Paradoxosomatidae found in Southeast Asia. The genus was described by Ralph Vary Chamberlin in 1923, and reviewed by Sergei Golovatch and Henrik Enghoff in 1994. At least 18 species are known from to Malaysia, Myanmar, and Thailand. One species, D. planata, has also been observed in Sri Lanka, the Andaman Islands, Seychelles, Java, Great Coco Island, and Fiji; however, this species has expanded its range by being transported through human activity. Several species have only recently been discovered, and some have yet to be officially described.
Xystodesmidae is a family of millipedes. Its members often have very small distributional areas, with many species only known from a single locality. They are found across the northern hemisphere, with peak diversity in the Appalachian Mountains, where one-third of the 300 or so species occur. They are particularly abundant in deciduous broadleaf forests in the Mediterranean Basin, Africa, Asia, Central and North America, and Russia. Information on basic taxonomy is scant for this family; for example, it is estimated that the genus Nannaria contains over 200 species, but only 25 were described as of 2006. By 2022, 78 species in Nannaria have been described.
Platydesmida is an order of millipedes containing two families and over 60 species. Some species practice paternal care, in which males guard the eggs.
Richard Lawrence Hoffman was an American zoologist known as an international expert on millipedes, and a leading authority on the natural history of Virginia and the Appalachian Mountains. He was a biology professor at Virginia's Radford College for almost thirty years, and curator of invertebrates at the Virginia Museum of Natural History for another twenty years. He co-founded the Virginia Natural History Society, described over 400 species of millipedes, and produced more than 480 scientific publications. He is commemorated in the scientific and/or common names of over 30 animal species, including the valley and ridge salamander and Hoffman's dwarf centipede.
Chordeumatida is a large order of millipedes containing some 1200 species with a nearly worldwide distribution. Also known as sausage millipedes, they grow and develop through a series of moults, adding segments until they reach a fixed number in the adult stage, which is usually the same for a given sex in a given species, at which point the moulting and the addition of segments and legs stop. This mode of development, known as teloanamorphosis, distinguishes this order from most other orders of millipedes, which usually continue to moult as adults, developing through either euanamorphosis or hemianamorphosis.
Siphoniulus is a poorly known genus of millipede containing only two living species: S. alba from Indonesia, and S. neotropicus from Mexico and Guatemala. An additional two fossil species are known from Cretaceous amber. Siphoniulus species are the only members of the family Siphoniulidae and order Siphoniulida, making Siphoniulida the smallest millipede order. Few specimens are known, and their classification is contentious, although most recent studies place them as basal members of the Helminthomorpha.
Tylobolus is a genus of millipedes in the order Spirobolida with seven known species found in western North America. It is in the family Spirobolidae, and is the type genus of the subfamily Tylobolinae. The genus was named by Orator F. Cook in 1904.
Hiltonius is a genus of cylindrical millipedes in the family Spirobolidae comprising 10 species ranging from the southwestern United States to Guatemala, with most species being found in Mexico. The genus was named by Ralph Vary Chamberlin in 1918, after Professor William A. Hilton of Pomona College who collected the type specimen of H. pulchrus.
Andrognathidae is a family of millipede in the order Platydesmida. There are about 17 genera and more than 30 described species in Andrognathidae.
Platydesmidae is a family of millipede in the order Platydesmida. There are at least 2 genera and more than 30 described species in Platydesmidae.
Paeromopus is a genus of large cylindrical millipedes endemic to the U.S. state of California. All species exceed 10 centimeters in length, and the largest, P. paniculus, reaching 16.5 cm is the longest millipede species in North America. The genus was named by German entomologist Ferdinand Karsch in 1881 and contains four species: three occupying small ranges in the Sierra Nevada mountains and one occupying a large range including the Sierra Nevada and much of Northern California to the Central Coast.
Brachycybe (Greek for "short head") is a genus of andrognathid millipedes with species in the United States and East Asia. In a rare example of paternal care in invertebrates, males of most species guard the eggs until they hatch.
Caseyidae is a family of millipedes in the order Chordeumatida. Adult millipedes in this family have 30 segments. There are about 7 genera and at least 40 described species in Caseyidae.
Conotylidae is a family of millipedes in the order Chordeumatida. Adult millipedes in this family have 30 segments. There are about 19 genera and at least 60 described species in Conotylidae.
Striariidae is a family of millipedes in the order Chordeumatida. Adult millipedes in this family have 30 segments. There are at least 3 genera and about 13 described species in Striariidae.
Chonaphini is a tribe of flat-backed millipedes in the family Xystodesmidae. There are about 6 genera and 19 described species in Chonaphini.
Xystocheirini is a tribe of flat-backed millipedes in the family Xystodesmidae. There are about 5 genera and more than 40 described species in Xystocheirini.
