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.
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.
Arrup is a genus of centipedes in the family Mecistocephalidae, native to Europe and Asia as far as Japan. Centipedes in this genus feature small telopodites on the second maxillae, the head and forcipular segment are elongate, the clypeus is almost completely areolate, and the poison glands in adult males are often deep inside the forcipules. These centipedes range from 1 cm to 5 cm in length. All species in this genus have 41 leg-bearing segments. Most are soil-dwellers but Arrup akiyoshiensis is a troglobiont.
Agnostrup is a genus of centipedes in the family Mecistocephalidae, native to Europe and Asia. Centipedes in this genus feature small telopodites without claws on the second maxillae and a robust basal denticle on the forcipular tarsungulum. These centipedes range from 2 cm to 3 cm in length. All species in this genus have 41 leg-bearing segments.
Geophilus persephones is a species of soil centipede in the family Geophilidae discovered in 1999. This species is named after Persephone, the queen of the underworld in Greek mythology, and found in caves in the Gouffre de la Pierre Saint-Martin. It has elongated antennae and legs as well as abundant sensory setae, and like other geophilomorhps it lacks sight, has a flattened trunk, and is well adapted to underground life. This species was the first troglomorphic geophilomorph ever discovered and one of the only two in existence along with Geophilus hadesi. Known from a single male specimen measuring 16.2 mm in length, this species has only 29 pairs of legs, one of only two species in the Geophilidae family to have so few leg pairs.
Dignathodontidae is a monophyletic clade of soil centipedes in the family Geophilidae found in the Mediterranean region, extending to Macaronesia, Caucasus, and western and central Europe. The clade is characterized by a gradually anteriorly tapered body, a short head with non-attenuated antennae, and a poorly sclerotized labrum with tubercles. The number of legs in this clade varies within as well as among species and ranges from 43 pairs to 153 pairs of legs. Species in this clade tend to have more leg-bearing segments and greater intraspecific variability in this number than generally found in the family Geophilidae.
Acanthogeophilus is a genus of soil centipedes in the family Geophilidae, found in the centro-west part of the Mediterranean region. The species in this genus are slender, 2-3 centimeters long, with 67 to 71 pairs of stout legs, peculiar spine-like processes on the ultimate legs, a claw-like pretarsus, complete coxo-pleural sutures, incomplete chitin-lines, absence of a carpophagous pit, possession of only basal denticles, and a transverse band porefield with scattered, anterior pores on the coxopleuron.
Geophilus electricus is a species of soil centipede in the family Geophilidae found across temperate Europe, especially Britain and Ireland. Originally discovered and named Scolopendra electrica in 1758, it was later moved to its own genus, Geophilus. As the first species described in this genus, it is considered by some to be the type species. It is yellowish-orange in color and can grow up to 45 millimeters, with 55 to 75 leg pairs, a distinct carpophagus fossae on the anterior sternites, and a distinctive arrangement of the coxal pores of the last leg pair. Like many geophilomorphans, G. electricus has been known to glow in the dark, most likely as a defensive maneuver.
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 arenarius is a species of soil centipede in the family Geophilidae found in northwest Africa, specifically near Annaba, Algeria. This species is frequently misidentified with G. electricus, and as part of the carpophagus species-complex, is closely related to both G. carpophagus and G. easoni, though it differs mainly by lacking a transverse suture on the head and peculiar integumental features (carpophagus-structures) along the trunk, as well as having relatively stouter antennae and forcipular coxosternite. G. arenarius is distinctly smaller at full growth than G. carpophagus, with usually blunter and more sclerotised tubercles lining the intermediate part of the labrum and a minute denticle at the basis of the forcipular tarsungula. It has fewer bristles lining the lateral parts of the labrum than G. easoni as well as a generally higher number of legs and a more greyish coloured trunk. The descriptions of 36 G. arenarius syntypes indicate that males of this species have 55 pairs of legs, whereas females have 55 to 59 leg pairs, with 57 as the most common number.
Geophilus anonyx is a species of soil centipede in the family Geophilidae found in Oregon. It was originally placed in the genus Brachygeophilus based on the lack of sternal pores, a character shared with the type species B. truncorum, however it was later moved to Geophilus.
Diphyonyx is a genus of soil centipedes in the family Geophilidae found in the Palearctic region. They are notable for the unusually shaped claws on the anterior part of the trunk, which are swollen and have anterior spurs enlarged into elongate projections. Centipedes in this genus have a forcipular coxosternite with a pair of anterior tubercles and feature no sternal pores. Most coxal organs open into a single pit on each coxopleuron. These centipedes range from 4 cm to 6 cm in length and have 65 to 81 pairs of legs.
Diphyonyx conjungens, formerly Geophilus conjungens, is a species of soil centipede in the family Geophilidae that has been recorded in the Balkan Peninsula, Anatolia, the southern Sporades islands, the most eastern parts of Turkish Armenia, the Pontic and Tauric mountains, and Crimea. It grows up to 60 millimeters long and bears 69–81 leg pairs in females, 67–79 in males, as well as 1–2 stout tubercles and 2–4 slender filaments on the mid-part of the labrum, an absence of condyles between the anterior trunk sterna, and a single, isolated pore on each coxo-pleuron.
Diphyonyx garutti, formerly Brachygeophilus sukacevi garutti, is a species of soil centipede in the family Geophilidae found in the most western part of the Caucasus range, north of the Black Sea. According to the original description, this species is characterized by 2–4 slender filaments on the mid-part of the labrum, condyles between the anterior trunk sterna, and a single, isolated pore on each coxo-pleuron. Since the original description based on 23 specimens in 1960, this species has not been recorded again.
Geophilus pygmaeus is a species of soil centipede in the family Geophilidae found in the Southern Limestone Alps, between the Bergamasque Prealps in the west and the Slovene Prealps in the east, and in the northernmost Dinarides. Past records from other areas are usually false. G. pygmaeus is less than 20 millimeters long and has 41–47 leg pairs. It differs from other European species of Geophilus by the shape of the forcipular apparatus and arrangement of coxal pores.
Pachymerellus is a genus of two species of centipedes, in the family Geophilidae. It was described by American biologist Ralph Vary Chamberlin in 1920. The smaller Mexican species, Pachymerellus dentifer, measures only 16 mm in length and has only 43 pairs of legs, whereas the larger species, P. zygethus, measures 33 mm in length and can have from 47 to 65 leg pairs.
Pachymerellus zygethus is a species of centipede in the Geophilidae family. It is endemic to Australia and New Zealand, and was first described in 1920 by American biologist Ralph Vary Chamberlin.
Nesomerium is a monotypic genus of centipedes in the family Geophilidae. It was described in 1953 by American myriapodologist Ralph Vary Chamberlin. The sole species is Nesomerium hawaiiense Chamberlin, 1953. Since the original description of this species based on a single specimen, no other specimens have been referred to this species or this genus, and some authorities express doubts about the validity of these taxa and their placement in the family Geophilidae.
