The Geophilomorpha, commonly known as soil centipedes, are epimorphic and bear upwards of 27 leg-bearing segments. They are eyeless and blind, and bear spiracles on all leg-bearing segments—in contrast to other groups, which usually bear them only on their 3rd, 5th, 8th, 10th, 12th, and 14th segments—a "mid-body break", accompanied by a change in tagmatic shape, occurring roughly at the interchange from odd to even segments. This group is the most diverse centipede order, with 230 genera. Centipedes in this order each have an odd number of leg-bearing segments ranging from 27 to 191. They also have 14–segmented antennae. This order is a monophyletic group including two suborders: the monophyletic Placodesmata, which contains Mecistocephalidae, and Adesmata, which includes the superfamilies Himantarioidea and Geophiloidea. Segment number is usually fixed by species in the family Mecistocephalidae, unlike the case in other families in this order, in which the segment number usually varies within each species. The name "Geophilomorpha" is from Ancient Greek roots meaning "formed to love the earth."
Pachymerium is a genus of centipedes in the family Geophilidae found mainly in the west Palearctic region and in south Africa. Centipedes in this genus feature an elongate head, scattered coxal pores, and sternal pores in a pair of anterior groups and a posterior transverse band; the forcipular coxosternite is broad, and the ultimate article of the forcipule has a prominent basal denticle.
The Geophilidae are a polyphyletic, cosmopolitan family of soil centipedes in the superfamily Geophiloidea containing the mostly defunct clades Aphilodontidae, Dignathodontidae, Linotaeniidae, Chilenophilinae, and Macronicophilidae. These centipedes are found almost worldwide.
Himantariidae is a monophyletic family of centipedes in the order Geophilomorpha and superfamily Himantarioidea, found almost exclusively in the Northern Hemisphere. Centipedes in this family feature a short head with a concave labral margin bearing a row of denticles, a single dentate lamella and some pectinate lamellae on each mandible, second maxillae with strongly tapering telopodites and slightly spatulate claws, and a stout forcipular segment with short forcipules and a wide tergite; the ultimate legs usually have no pretarsus, and the female gonopods are distinct and biarticulate.
Oryidae is a monophyletic family of soil centipedes belonging to the superfamily Himantarioidea.
Mecistocephalidae is a monophyletic family of centipedes in the order Geophilomorpha. It is the only family in the suborder Placodesmata. Most species in this family live in tropical or subtropical regions, but some occur in temperate regions. This family is the third most diverse in the order Geophiliomorpha, with about 170 species, including about 130 species in the genus Mecistocephalus.
Geophilus is a large, heterogeneous genus of soil centipedes in the family Geophilidae largely considered to be synonymous with Brachygeophilus. This genus is mostly Holarctic and characterized by a claw-shaped ultimate pretarsus, complete or nearly complete coxo-pleural sutures at the prosternum, and incomplete chitin-lines. Centipedes in this genus feature slightly elongate heads and labral intermediate parts with tubercles, the forcipules are usually poorly elongate with a single small tubercle at the base of each tarsungulum, and the anterior trunk metasternites usually have an anterior medial socket and a posterior transversally elongate pore-field. The generic name first appeared in Brewster's Edinburgh Encyclopaedia in 1814 as Geophilus electricus.
Linotaeniidae are a monophyletic clade of soil centipedes in the family Geophilidae found mostly in the temperate regions of the Holarctic as well as the south Andes. Species in the clade Linotaeniidae are characterized by a body that usually tapers toward the anterior tip; mandibles with a single pectinate lamella; second maxillae with coxo-sternite usually undivided and claws without projections; forcipular segment short, with tergite remarkably wide, forcipules evidently tapering; coxal organs opening through distinct pores on the ventral surface of the coxo-pleura. The number of legs in this clade varies within as well as among species and ranges from as few as 31 pairs of legs to as many as 83 leg pairs. Compared to most families in the suborder Adesmata, this clade features a modest number of leg-bearing segments and limited variation in this number within each species.
Schendylidae is a family of centipedes in the order Geophilomorpha found in the Americas, the Palearctic region, Africa, Madagascar, Australia, and southeast Asia, and also on some Pacific islands.
Strigamia is a genus of soil centipedes in the family Linotaeniidae found in temperate parts of the Holarctic region. Members of this family can be identified by their anteriorly tapering bodies, the extra claw on the forcipules, scattered coxal pores, and the distinctly swollen ultimate legs of the males. The generic name is from Latin striga, "strip," referring to its strip of bristles.
Tygarrup is a genus of centipedes in the family Mecistocephalidae, found mainly in southeast Asia and from the Seychelles to Hawaii. Although species in this genus can have either 43 or 45 leg-bearing segments, most of these species have 45 leg pairs. An undescribed Tygarrup species found in the Andaman Islands has 43 leg pairs. Centipedes in this genus are sometimes melanised in patches, and sternal glands are present the males of most species. These centipedes range from 2 cm to 6 cm in length. Tygarrup javanicus is one of the smallest of the mecistocephalid species and has become an invasive in greenhouses in Europe.
Ballophilidae is a monophyletic group of centipedes belonging to the order Geophilomorpha and superfamily Himantarioidea. Authorities now dismiss this group as a family, citing phylogenetic analysis, and instead refer to this clade as Ballophilinae, a possible subfamily within the family Schendylidae. Centipedes in this clade differ from others in the family Schendylidae by having bodies tapered toward the anterior tip, short heads, slender forcipules that are well apart, and an undivided lamina for the female gonopods. Centipedes in this clade are found in most tropical regions.
Zelanophilidae is a family of centipedes belonging to the order Geophilomorpha and superfamily Geophiloidea. Centipedes in this family are found in the Australasian region.
Gonibregmatidae are a paraphyletic family of soil centipedes belonging to the superfamily Geophiloidea.
Acanthogeophilus spiniger is a species of soil centipede in the family Geophilidae found in Northwest Africa. The original description of this species is based on a male specimen measuring 27 mm in length with 71 pairs of legs. It was first assigned to the genus Geophilus, but was moved to Acanthogeophilus in 1999 by Foddai and Minelli. Like other species in its genus, it is characterized by incomplete chitin lines, complete coxopleural sutures, stout legs, and a claw-like pretarsus.
Geophilus claremontus is a species of soil centipede in the family Geophilidae found in Claremont, California, after which it was named. It was incorrectly placed in the genus Brachygeophilus in 1929 by Attems, most likely based on the lack of sternal pores.
Ribautia is a genus of centipedes in the family Geophilidae. This genus was described by French myriapodologist Henry Wilfred Brolemann in 1909. Centipedes in this genus are found in South America, tropical Africa, Madagascar, the Arabian peninsula, Australia, New Zealand, and Melanesia.
Mecistocephalus is a genus of centipedes in the family Mecistocephalidae. It was described by British entomologist George Newport in 1843.
Maoriella is a genus of centipedes in the family Geophilidae. It was described by Austrian myriapodologist Carl Attems in 1903. Species in this genus are found in New Zealand, Australia, and Tahiti.
Gonibregmatus is a genus of centipedes in the family Gonibregmatidae. It was described by British entomologist George Newport in 1843.
