Cave-fauna
Guides
Abacionidae
crested millipedes
Abacionidae is a family of crested millipedes in the order Callipodida, established by Shelley in 1979. The family contains at least three genera—Abacion, Delophon, and Tetracion—with approximately 13 described species. Members of this family occur in both surface and cave habitats, with some species showing troglobiotic adaptations including reduced pigmentation and non-functional eyes.
Banksula
Banksula is a genus of harvestmen in the family Phalangodidae, comprising ten described species. All species are endemic to California, United States. The genus was established by Roewer in 1949 and named in honor of Nathan Banks, an American entomologist who described the type species. These harvestmen belong to the suborder Laniatores, a diverse group of short-legged, often heavily armored opilionids.
Brackenridgia
woodlice
Brackenridgia is a genus of small terrestrial isopods (woodlice) in the family Trichoniscidae, established by Ulrich in 1902. The genus contains nine described species distributed primarily in North America, with several species exhibiting troglomorphic adaptations for cave-dwelling. Species in this genus are typically found in moist, dark microhabitats including caves, forest litter, and rocky crevices.
Caecidotea racovitzai
Caecidotea racovitzai is a small freshwater isopod in the family Asellidae, originally described as Asellus racovitzai by Williams in 1970. This species belongs to a genus primarily composed of subterranean and groundwater-dwelling crustaceans. Records indicate it has been documented in the United States, specifically in Vermont. Like other members of Caecidotea, it is likely associated with groundwater habitats such as caves, springs, or interstitial environments, though specific ecological details remain poorly documented.
Calicina
Calicina is a genus of armored harvestmen (Opiliones) in the family Phalangodidae, established by Ubick & Briggs in 1989. The genus contains more than 20 described species. Members of this genus are characterized by their heavily sclerotized body armor, a defining feature of the family Phalangodidae. These harvestmen are part of the suborder Laniatores, which includes the majority of the world's harvestman diversity.
Cambaridae
Cambarid Crayfishes
Cambaridae is the largest family of freshwater crayfish, comprising over 400 species. The family is predominantly native to eastern North America and Mexico, with a small number of species in eastern Asia (genus Cambaroides) and the Caribbean (Cuba). Several species have become invasive outside their native ranges, while many others have restricted distributions and are threatened with extinction.
Cambarus tartarus
Oklahoma Cave Crayfish
Cambarus tartarus is a critically endangered cave-dwelling crayfish endemic to two caves in Delaware County, Oklahoma. Described in 1972, this species has one of the most restricted ranges of any North American crayfish. The IUCN assessed it as Critically Endangered in 2010, noting an extremely high risk of extinction in the immediate future due to its tiny geographic range and vulnerability to groundwater contamination.
Campodeidae
slender entrophs
Campodeidae is a family of small, pale, eyeless hexapods in the order Diplura, distinguished by two long, many-segmented cerci at the abdomen tip. The family contains at least 30 genera and approximately 280 described species, distributed across soil and cave habitats worldwide. Members range from 5–12 mm in length, with the largest species being the cave-dwelling Pacificampa daidarabotchi from Japan. Abdominal spiracles are absent. The family exhibits diverse ecological strategies, with many species adapted to subterranean environments showing troglomorphic features such as elongated appendages and enhanced sensory structures.
Cholevini
small carrion beetles
Cholevini is a tribe of small carrion beetles in the family Leiodidae, comprising over 20 genera and 200 described species. In North America, the tribe is represented by four genera: Catops (17 species), Sciodrepoides (3 species), and monotypic Prionochaeta and Catoptrichus. Species are primarily associated with decomposing organic matter, with most inhabiting forest environments. Some species occupy specialized habitats including tundra, caves, and rodent burrows. The tribe has a Holarctic distribution with some species restricted to North America extending south to Mexico.
Collembola
springtails
Collembola (springtails) are minute hexapods, traditionally grouped with insects but now recognized as a distinct class of non-insect hexapods. They are among the most abundant soil arthropods globally, with estimates of 200–1,800 individuals per cubic decimeter of forest soil. Most species measure 1–3 mm, though some reach 6 mm and the largest known species attains 17 mm. They occupy diverse habitats including soil, leaf litter, caves, rodent burrows, intertidal zones, ant and termite nests, freshwater surfaces, and snow fields. The group is defined by several unique morphological features: a ventral collophore on the first abdominal segment, a furcula (springing organ) on the third or fourth abdominal segment in most species, internal mouthparts (entognathy), and fused tibio-tarsal leg segments. They exhibit simple metamorphosis and continue molting throughout adult life, up to 50 times.
Cordioniscus
Cordioniscus is a genus of small terrestrial isopods (woodlice) in the family Styloniscidae. The genus contains approximately 18 described species. Members are classified within the suborder Oniscidea, the group containing all fully terrestrial isopods.
Cryptops
cave centipedes
Cryptops is a genus of centipedes in the family Cryptopidae, commonly referred to as cave centipedes. The genus has a worldwide distribution with numerous species documented across Europe, Asia, and other regions. Some species exhibit troglobitic adaptations, including Cryptops speleorex from Romania's Movile Cave, which has evolved in isolation for millions of years in a chemosynthetic ecosystem. DNA barcoding studies have revealed greater species diversity than previously recognized, with cryptic species and large genetic distances between morphologically similar taxa.
Damaeidae
Damaeidae is a family of oribatid mites (order Sarcoptiformes) comprising approximately 20 genera distributed across the Northern Hemisphere. Members are primarily fungivorous and inhabit decomposing organic matter including plant litter, mosses, decaying wood, and soil layers. Several species exhibit troglophilic tendencies, occurring in subterranean habitats such as caves and mountain scree systems. The family has undergone extensive taxonomic revision, with historically recognized families Belbidae, Belbodamaeidae, and Hungarobelbidae now synonymized under Damaeidae.
Enigmina
Enigmina is a genus of armored harvestmen in the family Phalangodidae, established by Ubick & Briggs in 2008. The genus contains at least two described species: Enigmina granita and Enigmina warrenorum. Members of this genus belong to the suborder Laniatores, a diverse group of short-legged harvestmen characterized by robust bodies and often elaborate defensive armor. The genus name reflects the enigmatic nature of these cryptic arachnids, which are poorly known in terms of their biology and ecology.
Entomobrya
slender springtails
Entomobrya is a genus of slender springtails in the family Entomobryidae, containing at least 270 described species. Members are characterized by elongated bodies and are among the most commonly encountered springtails in many terrestrial habitats. The genus has been documented across diverse environments including continental Europe, the Canary Islands, and cave systems in southern Spain. Species identification relies heavily on colour pattern and dorsal macrochaetotaxy, though colouration varies broadly within species and fades in preservative.
Hahnia
comb-tailed spiders, dwarf sheet spiders
Hahnia is the most species-rich genus of the comb-tailed spider family Hahniidae, with approximately 102 valid species distributed worldwide. These spiders are small, cryptic arachnids characterized by their distinctive spinneret arrangement. Most species are under 4 mm in body length as adults. The genus was established by C. L. Koch in 1841 and was formerly classified within Agelenidae until recognized as a distinct family. Species occur across diverse habitats including caves, forest litter, and under bark.
Haplophthalmus
Haplophthalmus is a genus of small terrestrial isopods (woodlice) in the family Trichoniscidae. The genus contains 47 described species, with several showing restricted geographic ranges that have led to conservation concerns. Two species, H. abbreviatus and H. rhinoceros, are listed as vulnerable on the IUCN Red List due to their limited distributions in the Balkans.
Heteromurus
Heteromurus is a genus of slender-bodied springtails established by Wankel in 1860. The genus contains at least three described species: H. margaritarius, H. nitidus, and H. tenuicornis. Members are placed in the subfamily Heteromurinae and are characterized by elongated antennae and a generally slender habitus compared to other entomobryomorph springtails. The genus has been subject to taxonomic revision, particularly regarding the subgenus Verhoeffiella, which includes cave-dwelling species showing troglomorphic adaptations.
Keroplatidae
Predatory Fungus Gnats, Fungus Gnats
Keroplatidae is a family of small, delicate flies in the order Diptera, commonly known as predatory fungus gnats. The family comprises approximately 950 described species, though true diversity is estimated to be substantially higher. Members are predominantly forest-dwelling insects associated with damp microhabitats where fungi occur. The family is notable for containing three genera—Arachnocampa, Orfelia, and Keroplatus—with bioluminescent larvae, commonly called "glowworms." Larval ecology varies: some feed on fungi, others are predatory, and many combine both strategies. The fossil record extends to the Cretaceous period.
Lirceus
Flat Waterslaters
Lirceus is a genus of freshwater isopod crustaceans in the family Asellidae, commonly known as flat waterslaters. The genus contains at least 18 described species distributed across southern Canada and the eastern United States, extending westward to the Great Plains. Many species inhabit caves and springs, particularly in the Interior Highlands region (Ozark and Ouachita Mountains), while others occupy surface streams and leaf pack habitats. Two species are listed as endangered or vulnerable on the IUCN Red List.
Mycetophilini
fungus gnats
Mycetophilini is a tribe of fungus gnats within the family Mycetophilidae, comprising approximately 8 genera and at least 220 described species. Members are small to medium-sized flies associated with fungal habitats. The tribe is distinguished from related groups primarily by genitalic characters and wing venation patterns. Adults are generally found in moist, shaded environments where their larval food sources occur.
Mysmenidae
dwarf cobweb weavers
Mysmenidae is a family of minute spiders comprising approximately 135-188 described species across 13-17 genera. Members are among the smallest known spiders, ranging from 0.75 to 3 mm in body length. The family is one of the least studied groups of orb-weaving spiders due to their diminutive size and cryptic habits. Many species exhibit kleptoparasitic behavior, inhabiting the webs of other spiders to steal prey.
Oniscidea
Woodlice, Pillbugs, Rock Slaters
Oniscidea is the suborder of terrestrial isopod crustaceans commonly known as woodlice, pillbugs, and rock slaters. This diverse group comprises over 5,000 described species that have successfully colonized land from ancestral marine isopod stock. They are characterized by a dorsoventrally flattened, segmented exoskeleton with seven pairs of walking legs, and occupy a wide range of habitats from forests and grasslands to caves and urban environments. Most species are nocturnal detritivores that play important roles in decomposition and nutrient cycling.
Opilioacaridae
Opilioacarid mites, Primitive mites
Opilioacaridae is the sole family in the order Opilioacarida, comprising approximately 13 genera of rare, relatively large mites (1.5–2.5 mm). These mites are considered primitive due to retention of six pairs of eyes and abdominal segmentation, traits lost in other mite lineages. Historically treated as distinct from both Acariformes and Parasitiformes, molecular phylogenetics now places them within Parasitiformes. The family exhibits a disjunct global distribution with populations in semi-arid and tropical regions, including caves, leaf-litter, and rock habitats.
Opilioacaroidea
mite harvestmen, opilioacarid mites
Opilioacaroidea is a small superfamily of arachnids comprising the single family Opilioacaridae, with approximately 25 described species. These organisms represent a phylogenetically significant group, often considered the most primitive living mites due to their retention of ancestral chelicerate characteristics. They occupy an intermediate position between mites and harvestmen (Opiliones), exhibiting morphological features of both groups. Their restricted distribution and specialized habitat requirements make them among the least studied arachnids.
Orconectes
Orconectes is a genus of cave-dwelling freshwater crayfish endemic to the eastern United States. The genus was erected in 1872 by Edward Drinker Cope and originally contained 85 species in 11 subgenera. Following a 2017 taxonomic review, most surface-dwelling species were transferred to the genus Faxonius, leaving approximately 8 obligate cave-dwelling species in Orconectes. These subterranean crayfish exhibit classic troglomorphic traits including depigmentation, reduced eyes or blindness, and elongated appendages. Some species are extremely long-lived, though earlier claims of 176-year lifespans for O. australis were revised to 22 years or less in a 2012 study.
Paronellidae
Paronellidae is a family of elongate-bodied springtails (Collembola) in the order Entomobryomorpha. The family contains approximately 18 genera and at least 90 described species. Members of this family are primarily distributed in tropical and subtropical regions, with many species adapted to subterranean habitats including caves. The family includes notable troglobitic genera such as Troglobius and Troglopedetes.
Peracarida
Amphipods, Isopods, and Allies
Peracarida is a superorder of malacostracan crustaceans comprising approximately 12,000 species across 13 orders. The group is defined by the presence of a marsupium (brood pouch) formed by oostegites—flattened plates on the basalmost leg segments of females. Members occupy marine, freshwater, and terrestrial habitats, ranging from minute interstitial forms to the giant isopod Bathynomus giganteus (76 cm) and giant amphipod Alicella gigantea (34 cm). The earliest known peracaridian, Oxyuropoda ligioides, dates to the Late Devonian (~360 mya).
Phrynidae
Phrynid Tailless Whipscorpions, whip spiders, tailless whip scorpions
Phrynidae is a family of amblypygid arachnids found in tropical and subtropical regions of North and South America. The family includes approximately 65 described species across five extant genera: Acanthophrynus, Heterophrynus, Paraphrynus, Phrynus, and the extinct genus †Britopygus. Species occupy diverse habitats including forests, caves, and subterranean environments. All species are nocturnal. Genetic studies indicate substantial cryptic diversity, with some nominal species likely comprising dozens of distinct lineages.
Psychodinae
Moth Flies, Drain Flies, Filter Flies, Sewer Flies
Psychodinae is the nominate subfamily of moth flies (Psychodidae), commonly known as drain flies or filter flies. Adults are small, hairy flies rarely exceeding 5–6 mm in length, with distinctive kidney-shaped eyes connected by an eye-bridge. The subfamily has a cosmopolitan distribution, including subantarctic islands. Larvae are aquatic or semi-terrestrial, developing in diverse moist habitats ranging from natural springs and phytotelmata to artificial environments like drains and sewage systems.
Pygmarrhopalites
A genus of springtails (Collembola: Symphypleona) in the family Arrhopalitidae. The genus was established by Vargovitsh in 2009. Multiple species have been described, including both epigean and troglobiont (cave-dwelling) forms. Some species exhibit troglomorphies including reduced pigmentation, elongated appendages, and modified foot complex.
Rhagidiidae
Rhagidiidae is a family of soft-bodied, predaceous soil mites in the order Trombidiformes. The family comprises approximately 28 genera and 150 species of whitish mites that inhabit soil environments, with many species showing adaptations to subterranean life. Established by Oudemans in 1922, the family received its modern systematic foundation through Zacharda's 1980 world revision. Many species exhibit troglomorphic traits including reduced eyes, elongated appendages, and depigmentation.
Rhaphidophoridae
cave crickets, camel crickets, spider crickets, cave wētā, sand treaders, sprickets
Rhaphidophoridae is a globally distributed family of wingless orthopterans comprising over 500 described species. Commonly called cave crickets, camel crickets, or spider crickets, these insects are characterized by elongated antennae, enlarged hind legs adapted for jumping, and a humpbacked body profile. They occupy diverse habitats including caves, forests, animal burrows, and human structures. All species are flightless and nocturnal, relying heavily on tactile and chemical sensory structures for navigation in dark environments. The family includes notable subfamilies such as Ceuthophilinae in North America, Macropathinae in the Southern Hemisphere, and Aemodogryllinae in Asia.
Sabaconidae
sabaconid harvestmen
Sabaconidae is a family of harvestmen (Opiliones: Dyspnoi) comprising approximately 50 described species. The family exhibits a disjunct distribution spanning eastern North America and temperate Eurasia, with notable diversity in the southern Appalachian Mountains and the Altai Mountains of Russia. Species-level taxonomy within the family has been complicated by cryptic diversification, particularly in widespread species such as Sabacon cavicolens, which shows evidence of multiple allopatric lineages separated by vicariance and rare long-distance dispersal events.
Sitalcina
Sitalcina is a genus of armoured harvestmen (Opiliones) in the family Phalangodidae, established by Nathan Banks in 1911. The genus contains approximately 10 described species, all endemic to western North America, primarily distributed in California and adjacent regions. These harvestmen belong to the suborder Laniatores, a group characterized by relatively short legs and heavily sclerotized body armor. Most species have been described from cave or deep-soil habitats, reflecting a troglomorphic or endogean lifestyle.
Tomoceridae
Tomoceridae is a family of springtails (Collembola) within the order Entomobryomorpha. Members are characterized by their elongated bodies and relatively long antennae compared to other springtail families. The family includes both surface-dwelling and cave-adapted species, with some showing pronounced troglomorphic traits such as eyelessness and depigmentation. Tomoceridae has a broad geographic distribution including Europe, Asia, Australia, and the Americas.
Tomocerus
elongate springtails
Tomocerus is a genus of elongate springtails (Collembola) in the family Tomoceridae, characterized by their relatively large size among springtails and distinctive body proportions. Species in this genus are distributed across multiple continents including Europe, Asia, and the Americas, with some species exhibiting troglomorphic adaptations in cave habitats. The genus has been subject to taxonomic revision, with species complexes such as the kinoshitai and ocreatus groups recognized. Tomocerus vulgaris is a notable species that has been studied for its life history and ecological interactions, including serving as prey for specialized predators such as harvestmen.
Zelotes pinos
Zelotes pinos is a species of ground spider in the family Gnaphosidae, described by Platnick and Shadab in 1983. As a member of the genus Zelotes, it shares characteristics typical of this diverse group of wandering hunters. The specific epithet "pinos" likely refers to the type locality in the Pinos Altos region of New Mexico, where the species was first documented. Like other gnaphosids, this spider is a nocturnal ground-dwelling predator.
Zygentoma
silverfishes, fishmoths, firebrats
Zygentoma is an order of wingless insects comprising approximately 550 described species, including silverfishes and firebrats. These insects represent one of the most ancient living lineages of insects, having diverged before the evolution of winged insects in the Carboniferous period. They are characterized by three long caudal filaments and ametabolous development with continued molting throughout life. Many species are associated with human dwellings where they feed on starchy materials, while others inhabit caves, leaf litter, or live as inquilines in ant and termite nests.