Subterranean
Guides
Speleobamini
Speleobamini is a tribe of rove beetles in the subfamily Pselaphinae, established by Park in 1951. Members of this tribe are small, highly specialized beetles associated with subterranean and cave environments. The tribe is part of the diverse Pselaphinae radiation, which contains numerous microhabitat specialists. Speleobamini represents one of several lineages within Pselaphinae that have adapted to dark, moist habitats.
Speleomaster
Speleomaster is a genus of armoured harvestmen (Opiliones: Laniatores) described by Briggs in 1974. The genus contains at least two species, both endemic to subterranean lava tube environments in southern Idaho's Snake River Plain. As members of the family Cryptomastridae, these harvestmen represent a specialized lineage adapted to cave life.
Sphodrini
Sphodrini is a tribe of ground beetles in the family Carabidae, subfamily Platyninae. The tribe comprises more than 30 genera and at least 910 described species. Members of this tribe exhibit considerable diversity in geographic distribution, ranging from the Himalayas and East Asia to Europe and the Middle East. Some genera, such as Pristosia, show complex biogeographic patterns associated with Tertiary Tibetan faunal components and Himalayan uplift.
Stenasellidae
Stenasellidae is a family of stygobiotic (obligate subterranean aquatic) isopods in the suborder Asellota. The family comprises approximately 10 genera including Stenasellus, Metastenasellus, and Parastenasellus, with species distributed across groundwater habitats in Africa, the Middle East, southern Europe, and Southeast Asia. These crustaceans are exclusively adapted to life in continental underground waters including caves, wells, and interstitial aquifers. Their evolutionary history has been shaped by Quaternary climatic events including aridification in tropical zones and glaciations in temperate regions.
Stygobromus
Stygobromus is a genus of subterranean freshwater amphipods in the family Crangonyctidae, comprising 134 described species. The genus is primarily distributed in North America, with a smaller number of species in the Palearctic region including Siberia. Many species are narrow endemics restricted to specific groundwater systems, and several are listed as endangered or vulnerable by the IUCN; one species, S. lucifugus, is extinct.
Stygoparnus
Comal Springs dryopid beetle (for sole species S. comalensis)
Stygoparnus is a monotypic genus of dryopid beetles containing the single species Stygoparnus comalensis, known as the Comal Springs dryopid beetle. The genus is endemic to central Texas spring systems fed by the Edwards Aquifer. Its sole member is a federally endangered, subterranean-obligate aquatic beetle with vestigial eyes and reduced pigmentation. The genus represents the only known aquatic lineage within the family Dryopidae.
Stygoparnus comalensis
Comal Springs dryopid beetle
Stygoparnus comalensis is a federally endangered, subterranean-obligate dryopid beetle endemic to three spring systems in the Edwards Aquifer region of central Texas. Adults are approximately 2 mm long with vestigial eyes and undeveloped wings, reflecting their troglobitic ancestry. The species exhibits extreme population genetic structure with no gene flow among localities, indicating evolutionary isolation. Captive studies reveal strong habitat preferences for wood substrates and specific phototactic responses to light wavelength. The beetle serves as a surrogate species for monitoring aquifer health and faces threats from groundwater extraction, pollution, and drought-induced springflow reduction.
Stygoporus
Stygoporus is a monotypic genus of diving beetles (family Dytiscidae) containing the single species Stygoporus oregonensis. The genus was described in 1994 based on specimens collected from an Oregon bathroom in 1984. No additional specimens were reported until 2014–2016, making this one of the most poorly known beetle genera in North America.
Stygothrombidiidae
Stygothrombidiidae is a family of mites in the order Trombidiformes. Members are associated with subterranean freshwater habitats, particularly hyporheic zones and groundwater systems. The family is relatively small and poorly documented, with most known species placed in the genus Stygothrombium. These mites represent an example of adaptation to permanent darkness and interstitial aquatic environments.
Stygothrombium
Stygothrombium is a genus of mites in the family Stygothrombiidae, order Trombidiformes. It belongs to the diverse group of prostigmatid mites, which includes many parasitic and predatory forms. The genus was established by K.H. Viets in 1932. Members of this genus are associated with subterranean or groundwater habitats, reflecting the 'stygo-' prefix in its name.
Styracosceles
New Mexico camel cricket
Styracosceles is a genus of camel crickets in the family Rhaphidophoridae, established by Hubbell in 1936. The genus contains at least four described species distributed in western North America, including the New Mexico camel cricket (Styracosceles neomexicanus). These crickets are part of the subfamily Ceuthophilinae and are found in arid and semi-arid habitats.
Taracus
Taracus is a genus of small harvestmen (Opiliones) in the family Taracidae. Most species inhabit limestone and lava caves in western North America, with body lengths ranging from 2.0 to 5.5 mm. The genus contains 14 described species as of 2023, predominantly distributed across the United States with limited representation in Russia.
Texamaurops
Texamaurops is a genus of small rove beetles (Staphylinidae: Pselaphinae) established by Barr & Steeves in 1963. The genus contains at least one described species, Texamaurops reddelli, commonly known as the Kretschmarr Cave mold beetle. Members of this genus are associated with cave environments and belong to the diverse tribe Batrisini within the ant-loving beetle subfamily Pselaphinae.
Texoreddellia
Texoreddellia is a monotypic genus of nicoletiid silverfish described by Wygodzinsky in 1973. The genus contains a single described species, Texoreddellia texensis. As a member of Nicoletiidae, it belongs to a family of small, eyeless, wingless insects adapted to subterranean or cryptic habitats. The genus is known from limited observations and specimens.
Ticrania
Ticrania is a genus of planthoppers in the family Dictyopharidae, described by Emeljanov in 2006. It belongs to the tribe Orgeriini, a group of flightless, often subterranean planthoppers with fossorial (burrowing) forelegs. Members of this genus are poorly known and likely inhabit sandy or loose soil environments associated with plant roots.
Tolus
Tolus is a monotypic genus of harvestmen in the family Phalangodidae, described by Goodnight & Goodnight in 1942. The sole described species, Tolus appalachius, is known only from two caves in Tennessee, United States. This genus represents a rare example of cave-adapted opilionid fauna in the Appalachian region.
Tolus appalachius
Appalachian Cave Harvestman
Tolus appalachius is a small, eyeless cave-dwelling harvestman endemic to Tennessee. It is the sole described species in the genus Tolus. First described in 1942, this troglobitic arachnid is known from only a handful of cave systems in the Appalachian region. Its highly restricted distribution and specialized subterranean habitat make it vulnerable to environmental disturbances.
Trama
root aphids
Trama is a genus of aphids in the family Aphididae, tribe Tramini. These insects are commonly known as root aphids due to their subterranean feeding habits. The genus was established by von Heyden in 1837 and is distinguished from other aphid genera by morphological adaptations for life below ground.
Trechini
Trechini is a large and diverse tribe of small ground beetles in the family Carabidae, comprising over 270 genera and more than 2,400 described species worldwide. Members are typically diminutive, often less than 5 mm in length, with many species measuring 1 mm or less. The tribe exhibits remarkable habitat breadth, occurring in terrestrial, subterranean, and high-altitude mountain environments across all continents except Antarctica, though fossil evidence indicates former presence there. Trechini includes numerous cave-adapted lineages, making it the most diverse and cave-specialized group among Carabidae tribes in subterranean habitats.
Trechus tuckaleechee
Trechus tuckaleechee is a species of ground beetle in the subfamily Trechinae, described by Barr in 1962. It belongs to the genus Trechus, a large and widespread group of small carabid beetles commonly known as blind beetles or trechine ground beetles. The species epithet 'tuckaleechee' likely references Tuckaleechee, a location in Tennessee, USA, suggesting a restricted geographic distribution. Like other Trechus species, it is presumably adapted to subterranean or cryptic habitats.
Trichoniscidae
Trichoniscidae is a family of terrestrial isopods (woodlice) notable for containing the most abundant British woodlouse, *Trichoniscus pusillus*. The family exhibits exceptional ecological diversity, with many species occupying subterranean habitats in karst regions across Europe, while others have secondarily adapted to aquatic or amphibious lifestyles. Multiple genera contain troglobiotic (obligate cave-dwelling) species, particularly in the Dinaric Karst, which harbors significant diversity of this family. Some species demonstrate unique morphological adaptations for cave life, including elongated appendages and modified mouthparts.
Trichopetalidae
Trichopetalidae is a family of small millipedes in the order Chordeumatida. Adults possess 28 or 30 body segments, counting the collum as the first and the telson as the last. The family comprises seven genera and approximately 43 species, with members exhibiting diverse ecological strategies ranging from surface-dwelling to obligate cave-dwelling (troglobitic) lifestyles.
Trigonaspis radicola
Trigonaspis radicola is a species of gall wasp in the family Cynipidae. The species is known for inducing root galls on oak species (Quercus), distinguishing it from many cynipids that form galls on above-ground plant parts. Like other members of the tribe Cynipini, it has a complex life cycle involving alternating sexual and asexual generations, typically associated with different oak host species or plant structures. The species name 'radicola' (meaning 'root-dwelling') reflects its distinctive subterranean gall-forming habit.
Troglomethes leechi
false soldier beetle
Troglomethes leechi is a species of false soldier beetle in the family Omethidae. The species was described by Wittmer in 1970 and is known from North America. Members of the genus Troglomethes are associated with subterranean or cave-like habitats.
Troglopina
Troglopina is a subtribe of soft-bodied plant beetles within the family Melyridae. Members of this group are characterized by adaptations associated with subterranean or cave-dwelling lifestyles, as reflected in their name derived from 'troglodyte.' The subtribe includes genera such as Troglops, which exhibit morphological modifications for life in dark, humid environments. These beetles represent a specialized lineage within the diverse Melyridae family.
Typhlobius kebus
Typhlobius kebus is a lithobiomorph centipede described by Chamberlin in 1922. It belongs to the genus Typhlobius, a group of lithobiid centipedes. The species has been documented from California, USA. Very little is known about its biology or ecology.
Typhlonesticus silvestrii
Silvestri's Cave Spider
Typhlonesticus silvestrii is a troglobitic spider in the family Nesticidae, first described by Fage in 1929. The species is endemic to cave systems and exhibits adaptations typical of obligate cave-dwellers, including reduced pigmentation and elongated appendages. It represents one of the specialized members of the genus Typhlonesticus, which comprises European cave spiders with restricted distributions. The species was originally described under the genus Nesticus before being transferred to Typhlonesticus.
Typhlusechus singularis
Typhlusechus singularis is a species of darkling beetle (Tenebrionidae) described by Linell in 1897. The genus Typhlusechus contains few described species and is characterized by reduced or absent eyes, an adaptation associated with subterranean or cave-dwelling habits. This species is part of a group of tenebrionids that have evolved morphological specializations for life in darkness, including elongated appendages and depigmentation. Records indicate extremely limited observation data, with only 4 documented observations in iNaturalist.
Vitacea polistiformis
grape root borer, Grape Root Borer Moth
Vitacea polistiformis, commonly known as the grape root borer, is a clearwing moth in the family Sesiidae. It is a significant agricultural pest of grapevines (Vitis spp.) in the eastern and midwestern United States, where larval feeding on roots causes 'slow vine decline' that may take 5–10 years to become visible aboveground. Adults are Batesian mimics of Polistes paper wasps. As few as nine larvae can kill a mature vine with an 8-inch base circumference.
Xenotrechus
Xenotrechus is a genus of ground beetles (Carabidae) described by Barr & Krekeler in 1967. It contains two described species: X. condei and X. denticollis. The genus belongs to the tribe Trechini within the subfamily Trechinae, placing it among the small, often eyeless or reduced-eyed beetles adapted to subterranean or specialized habitats.
Xenotrechus condei
Northern Xenotrechus Cave Beetle
Xenotrechus condei is a cave-dwelling ground beetle in the family Carabidae, subfamily Trechinae. It is one of several species in the genus Xenotrechus, a group specialized for subterranean habitats. The species was described in 1967 from specimens collected in the United States. It represents a lineage of beetles that have adapted to permanent darkness and associated cave conditions.
Xenotrechus denticollis
Southern Xenotrechus Cave Beetle
Xenotrechus denticollis is a troglobitic ground beetle in the family Carabidae, described by Barr & Krekeler in 1967. It belongs to a genus of cave-dwelling beetles endemic to the southern United States. The species epithet 'denticollis' refers to toothed characteristics of the pronotum or neck region.
Zuphiini
Zuphiini is a tribe of ground beetles in the family Carabidae, established by Bonelli in 1810. The tribe contains at least 23 genera and more than 120 described species with a worldwide distribution. Members of the genus Coarazuphium within this tribe include obligate cave-dwelling (troglobitic) species found in iron ore caves in Brazil's Carajás region, which harbors the highest diversity of obligatory cave-dwelling beetles in the country.