Xystodesmidae

Millipedes in this family 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. == Description ==

Xystodemids are characterized by a relatively broad and compact body shape and one or more spines on the second leg-segments (prefemoral spines) in most species. Millipedes in this family range from 8 mm to 85 mm in length, with moderately convex bodies that taper toward both the front and especially the rear end. The antennae are slender and long. The paranota are normally large and prominent. This family also includes the cave-dwelling genus Devillea, notable for having more than the 20 segments (counting the collum as the first segment and the telson as the last) usually found the Polydesmida. For example, in the species D. tuberculata, adult females have 22 segments and adult males have 21, with a corresponding increase in the number of leg pairs (35 in adult females and 32 in adult males, excluding the gonopods). Some species in this genus also exhibit variation in segment number within the same sex, for example, in D. subterranea, adult males can have as few as 19 segments or as many as 23. The species D. doderoi has the maximum number of segments recorded in this family (29, including the telson). ==Classification==

The family is divided into three subfamilies: the Melaphinae with around 10 species, the Parafontariinae with a dozen species in a single genus, and the Xystodesminae, with many genera and species. each ending in the suffix "-ini", although taxonomist Richard Hoffman stated in his 1999 checklist: "I am by no means satisfied that this is the definitive arrangement, nor that the tribal divisions of the Xystodesminae are entirely satisfactory either." Apheloriini Hoffman, 1980 • Apheloria • Appalachioria • Brachoria • Brevigonus • Cheiropus • Cleptoria • Croatania • Deltotaria • Dixioria • Dynoria • Falloria • Furcillaria • Lyrranea • Prionogonus • Rudiloria • Sigmoria • Stelgipus Chonaphini Verhoeff, 1941 • Chonaphe • Metaxycheir • Montaphe • Selenocheir • Semionellus • Tubaphe Devilleini Brölemann, 1916 • Devillea Nannarini Hoffman, 1964 • Nannaria • Oenomaea Orophini Hoffman, 1964 • Kiulinga • Pamelaphe • Orophe Pachydesmini Hoffman, 1980 • Dicellarius • Pachydesmus • Thrinaxoria Rhysodesmini Brolemann, 1916 • Boraria • Cherokia • Erdelyia • Gyalostethus • Pleuroloma • Rhysodesmus • Stenodesmus • Caralinda • Gonoessa • Lourdesia • Parvulodesmus Sigmocheirini Causey, 1955 • Ochthocelata • Sigmocheir Xystocheirini Cook, 1904 • Anombrocheir • Motyxia • Parcipromus • Wamokia • Xystocheir Xystodesmini Hoffman, 1980'', a species of the Pacific Northwest of the U.S. and Canada • Harpaphe • Isaphe • Koreoaria • Levizonus • Riukiaria • Thrinaphe • Xystodesmus • Yaetakaria ==See also==