Troglobiont
Guides
Anthroleucosomatidae
Anthroleucosomatidae is a family of small to medium-sized millipedes in the order Chordeumatida, with approximately 19 genera and at least 40 described species. The family exhibits a core distribution centered on the Balkans and Caucasus region, extending eastward to Iran and central Siberia, with one highly disjunct North American species in Washington State. Many species are troglobionts (obligate cave-dwellers), including the world's deepest-occurring millipede, Heterocaucaseuma deprofundum, found below 2,000 meters in Krubera-Voronja Cave. The family shows exceptional diversity in the Caucasus, where 15 new genera and 36 new species were described in a single monograph.
Arrhopalites
springtails
Arrhopalites is a genus of globular springtails (Collembola: Symphypleona) in the family Arrhopalitidae. The genus comprises approximately 40 valid species, with roughly half considered troglobionts—obligate cave-dwelling organisms. Species occur across diverse habitats including cave systems, forest leaf litter, and soil environments, with distribution spanning the Neotropical Region, Asia, Europe, and other regions. The genus is taxonomically significant for phylogenetic studies of Symphypleona, though many aspects of its biology remain understudied.
Arrhopalitidae
Arrhopalitidae is a family of springtails (Collembola) in the order Symphypleona, superfamily Katiannoidea. The family includes three genera: Arrhopalites, Pygmarrhopalites, and Troglopalites. Many species are obligate cave-dwellers (troglobionts) exhibiting pronounced troglomorphy, including reduced pigmentation, elongated appendages, and modified sensory structures. The family has a sister-group relationship with Katiannidae.
Chordeumatida
Sausage Millipedes, Spinning Millipedes
Chordeumatida is a large order of millipedes containing over 1,100 species, commonly known as sausage millipedes or spinning millipedes. Members of this order are distinguished by their teloanamorphic development—adding segments through molts until reaching a fixed adult number, after which molting ceases. They are notable for possessing spinnerets on their telsons that produce silk used to construct protective chambers for molting and egg-laying. The order exhibits considerable morphological diversity, with species ranging from 3.5 to 42 mm in length and displaying both cylindrical and flat-backed body forms.
Conotylidae
Conotylidae is a family of millipedes in the order Chordeumatida, containing approximately 19 genera and at least 60 described species. Adult members possess 30 body segments, counting the collum as the first and the telson as the last. The family exhibits its highest diversity in northwestern North America, where five of six subfamilies and ten of fourteen previously described genera occur. Several species are troglobiotic, restricted to cave environments, and some are considered climatic relicts from the Pleistocene.
Darlingtonea
Darlingtonea is a monotypic genus of cave-dwelling ground beetles (Carabidae) containing a single species, D. kentuckensis. This trechine beetle is endemic to eastern Kentucky's karst cave systems, where it functions as a top terrestrial predator specialized for high-humidity subterranean environments. The genus exhibits extreme physiological specialization, with narrow humidity tolerance identified as a critical vulnerability to climate change.
Macrosternodesmidae
Macrosternodesmidae is a family of flat-backed millipedes in the order Polydesmida, primarily distributed in western North America with some European representatives. The family contains approximately 9 genera and 16 described species, though taxonomic status remains disputed—some authorities treat it as a junior synonym of Trichopolydesmidae, while others recognize it as valid with two subfamilies: Macrosternodesminae and Nearctodesminae. Many species are troglobionts restricted to cave systems.
Myriapoda
myriapods
Myriapoda is a subphylum of terrestrial arthropods comprising approximately 13,000–16,000 described species across four extant classes: Chilopoda (centipedes), Diplopoda (millipedes), Pauropoda, and Symphyla. All myriapods are obligate terrestrial, characterized by elongated bodies with numerous segments bearing legs. The group represents one of the earliest arthropod lineages to colonize land, with fossil evidence dating to the Late Silurian–Early Devonian boundary. Myriapods exhibit diverse ecological roles: centipedes are primarily nocturnal predators using venomous forcipules, while millipedes, pauropods, and symphylans function predominantly as detritivores in soil and leaf litter ecosystems.
Nicoletiidae
Nicoletiidae is a family of primitive wingless insects in the order Zygentoma. Members are predominantly subterranean, inhabiting soil, caves, and mesovoid shallow substratum (MSS) environments. Many species exhibit troglobiotic adaptations including lack of eyes and pigmentation. The family contains at least four subfamilies (Atelurinae, Nicoletiinae, Cubacubaninae, Coletiniinae, Subnicoletiinae) with over 100 described genera. Some species are commensals in social insect nests, such as Allotrichotriura saevissima in fire ant nests.
Protaphorura
Protaphorura is a genus of springtails (Collembola) in the family Onychiuridae, established by Absolon in 1901. The genus contains numerous species distributed across the Palearctic region, with particular diversity in southern Siberia and the Far East of Russia. Several species are obligate cave-dwellers (troglobionts), exhibiting specialized adaptations to subterranean environments. The genus is taxonomically well-studied, with identification keys available for over 85 Palearctic species based on morphological characters including pseudocellar formulae, postantennal organ structure, and chaetotaxy.
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.
Scoterpes
Scoterpes is a genus of troglobiotic millipedes in the family Trichopetalidae, order Chordeumatida. Established by Cope in 1872, the genus comprises exclusively cave-dwelling species found in North America. The genus was revised in 2010, with fifteen recognized species including eight newly described taxa. At least two species, S. copei and S. ventus, likely represent superspecies complexes consisting of multiple genetically isolated populations.
Scoterpes sollmani
Scoterpes sollmani is a troglobiotic millipede described by Lewis in 2000 from cave systems in southern Indiana. As a member of genus Scoterpes, it is one of multiple cave-adapted species in this exclusively troglobiotic group. The species belongs to the small family Trichopetalidae within the order Chordeumatida, a group of small-bodied millipedes. No specific morphological details distinguishing S. sollmani from congeners are provided in available sources.