Eyeless
Guides
Adranes
ant-loving beetles
Adranes is a genus of obligately myrmecophilous beetles in the rove beetle family Staphylinidae. These small beetles are entirely dependent on ants of the genus Lasius, living as inquilines within their nests. The six described species share extreme morphological adaptations for this lifestyle, including complete eyelessness, reduced mouthparts, and highly modified antennae. They are known from North America, with species distributed across the United States and Pacific coast regions.
Alaocybites
A genus of small, eyeless or microphthalmic weevils in the family Raymondionymidae. Originally described from California with two eyeless species, the genus was later discovered in the Russian Far East (Primorsky Kray) and represented by a fossil in Alaska. The genus is characterized by reduced or absent eyes and the absence of tarsomere IV on all legs, traits associated with edaphic (soil-dwelling) habits.
Anillinus albrittonorum
Anillinus albrittonorum is a species of minute ground beetle described in 2021. It belongs to the tribe Anillini, a group of tiny, eyeless, wingless beetles adapted to subterranean or soil-dwelling habitats. The species was named in honor of the Albritton family. Like other members of its genus, it is presumed to inhabit deep soil and leaf litter layers.
Anillinus arenicollis
Anillinus arenicollis is a species of minute ground beetle in the family Carabidae. It belongs to a genus of small, often eyeless or reduced-eyed beetles adapted to subterranean or soil-dwelling habits. The species epithet 'arenicollis' suggests association with sandy habitats. Members of Anillinus are among the smallest carabid beetles and are poorly known due to their cryptic lifestyle.
Anillinus chilhowee
Anillinus chilhowee is a small ground beetle (Carabidae) in the tribe Bembidiini, described by Sokolov in 2011. It belongs to the genus Anillinus, a group of minute, eyeless or nearly eyeless beetles adapted to subterranean or deep soil habitats. The species epithet references the Chilhowee region, likely indicating its type locality in the southeastern United States.
Anillinus choestoea
Anillinus choestoea is a small, eyeless ground beetle in the family Carabidae, described by Thomas C. Barr in 1962. It belongs to a genus of anilline beetles characterized by reduced eyes or complete anophthalmia, elongated bodies, and subterranean habits. The species is known from cave and deep soil habitats in the Appalachian region of the eastern United States. Like other members of Anillinus, it exhibits morphological adaptations for life in darkness, including depigmentation and elongated appendages.
Anillinus dentatus
Anillinus dentatus is a species of minute ground beetle in the family Carabidae. Members of the genus Anillinus are eyeless, subterranean beetles adapted to life in soil and cave environments. The specific epithet "dentatus" refers to toothed characteristics, likely of the mandibles or elytral margins. These beetles are part of the diverse North American cave beetle fauna, with species in this genus primarily distributed in the eastern and central United States.
Anillinus docwatsoni
A small ground beetle in the tribe Bembidiini, described from the United States in 2004. Members of the genus Anillinus are minute, eyeless or nearly eyeless beetles adapted to subterranean or deep soil habitats. The specific epithet honors the bluegrass musician Doc Watson.
Anillinus jancae
Anillinus jancae is a small, eyeless ground beetle in the tribe Bembidiini. It was described by Thomas C. Barr in 1995 based on specimens from Kentucky. The species belongs to a genus of minute carabids adapted to subterranean or deep soil habitats. Like other Anillinus species, it exhibits troglomorphic traits including reduced pigmentation and vestigial eyes.
Anillinus magazinensis
Anillinus magazinensis is a small ground beetle in the family Carabidae, described in 2004 from specimens collected in Arkansas, USA. It belongs to the genus Anillinus, a group of minute, eyeless, wingless beetles adapted to subterranean or deep soil habitats. The species epithet refers to Magazine Mountain, the type locality in the Ozark Mountains.
Anillinus murrayae
Anillinus murrayae is a small ground beetle in the family Carabidae, described by Sokolov and Carlton in 2004. It belongs to the genus Anillinus, a group of minute, eyeless or nearly eyeless beetles adapted to subterranean and soil-dwelling lifestyles. The species is known from the United States. Like other members of its genus, it likely inhabits deep soil and leaf litter layers in forested environments.
Anillinus sinuaticollis
Anillinus sinuaticollis is a small ground beetle described by Jeannel in 1963. It belongs to the tribe Anillina within Carabidae, a group characterized by reduced or absent eyes and subterranean habits. The species is known from the United States, consistent with the broader North American distribution of the genus.
Anillinus unicoi
Anillinus unicoi is a small ground beetle species in the family Carabidae, described in 2011 from the Unicoi Mountains region of the southern Appalachians. It belongs to the genus Anillinus, a group of minute, eyeless or nearly eyeless beetles adapted to subterranean or deep soil habitats. The species epithet refers to the Unicoi Mountains, which span the Tennessee-North Carolina border. Like other anillines, it likely inhabits moist forest floor environments and exhibits reduced pigmentation and vision associated with life in dark microhabitats.
Anillinus virginiae
Anillinus virginiae is a species of ground beetle in the family Carabidae, described by Jeannel in 1963. It belongs to the genus Anillinus, a group of small, eyeless or reduced-eye beetles adapted to subterranean or cryptic habitats. The species is known from the United States, with the specific epithet suggesting a type locality in Virginia. Like other members of the subtribe Anillina, it is likely associated with soil and leaf litter environments.
Batrisodes venyivi
Helotes Mold Beetle
Batrisodes venyivi, commonly known as the Helotes Mold Beetle, is a small, eyeless troglobitic beetle in the family Staphylinidae. It is endemic to eight caves in Bexar County, Texas, and was listed as endangered under the U.S. Endangered Species Act in 2000. The species exhibits classic cave-adapted traits including elongated antennae, legs, and sensory setae. Very little is known about its behavior, population trends, or life history due to the logistical challenges of accessing its subterranean habitat.
Battigrassiella
Battigrassiella is a genus of silverfish in the family Nicoletiidae, described by Paclt in 1963. The genus contains one described species, Battigrassiella wheeleri. Nicoletiidae are eyeless, wingless insects typically found in soil and leaf litter habitats. The genus has been treated as a synonym of Grassiella in some taxonomic databases, indicating taxonomic uncertainty.
Blaniulus guttulatus
Spotted Snake Millipede
Blaniulus guttulatus, the spotted snake millipede, is a small, eyeless millipede native to Central and Western Europe that has been widely introduced to North America, Australia, and remote Atlantic islands. It is characterized by its slender, pale body with distinctive red ozadenes (defensive glands) on each segment. The species thrives in anthropogenic habitats and can become an agricultural pest, particularly during drought conditions.
Brachycybe lecontii
Feather Millipede
Brachycybe lecontii is a small, eyeless, pink-colored millipede endemic to the eastern United States. It is one of the few known social millipedes, forming multi-generational colonies and distinctive "pinwheel" aggregations during feeding. Males exclusively provide paternal care of eggs during a 3–4 week incubation period; egg survival depends entirely on this care. The species is obligately fungivorous, feeding on diverse fungi, and possesses specialized cuticular structures possibly adapted for mycophagy.
Catopocerinae
Catopocerinae is a subfamily of small beetles within Leiodidae, containing at least two extant genera—Catopocerus and Pinodytes—in North America, plus the extinct genus Archaeocerus from Cretaceous Myanmar amber. All described extant species are eyeless and wingless, inhabiting forest soil and litter. The subfamily has been revised taxonomically with numerous new species described, particularly in western North America.
Catopocerus
Catopocerus is a genus of small beetles in the family Leiodidae, subfamily Catopocerinae. These beetles are primarily subterranean or cave-dwelling, with reduced eyes and elongated appendages adapted to dark environments. The genus was established by Motschulsky in 1870 and contains species distributed across parts of North America and Eurasia. Members of this genus are among the most troglomorphic beetles in their family.
Catoptrichus
Catoptrichus is a genus of small carrion beetles in the family Leiodidae, subfamily Cholevinae. Members of this genus are eyeless, subterranean-adapted beetles associated with cave and soil habitats. The genus was established by Andrew Murray in 1856 and is placed in the subtribe Catopina.
Cicurina madla
Madla Cave meshweaver, Madla's Cave Meshweaver
Cicurina madla is a federally endangered troglobitic spider endemic to karst caves in Bexar County, Texas. First described by Gertsch in 1992, it was synonymized with Cicurina venii in 2018. The species is completely eyeless and exhibits morphological adaptations to cave life, including elongated legs relative to body size. It is known from only eight to nine caves and depends on cave crickets as a food source.
Cirolanides
Cirolanides is a genus of eyeless isopods in the family Cirolanidae, first described by Benedict in 1896. The genus contains two species: C. texensis and C. wassenichae. Members are characterized by reduced visual structures and specialized appendages adapted for subterranean life. These crustaceans represent a lineage adapted to dark, aquatic habitats.
Diplura
Two-pronged Bristletails
Diplura is an order of small, wingless, eyeless hexapods within the class Entognatha, characterized by a distinctive pair of caudal appendages (cerci) that give them their common name "two-pronged bristletails." The group comprises approximately 800 described species worldwide, ranging from 2 to 50 mm in length, with some species reaching up to 8 cm. They inhabit moist soil, leaf litter, humus, and caves across all continents except Antarctica. Diplurans possess concealed mouthparts (entognathous), long bead-like antennae, and the ability to autotomize their cerci when threatened.
Gabunillo
Gabunillo is a genus of small, eyeless, pigmentless woodlice in the family Armadillidae. Described in 1983 from Gabon, it now includes four species found in Gabon, Brazil, and São Tomé. Members of this genus are characterized by their ability to fully conglobate (roll into a ball), complete absence of eyes, and lack of pseudotracheae. The genus is distinguished from the similar Synarmadillo by cephalon structure, telson shape, and the absence of ventral teeth on thoracic segments.
Glacicavicola
Western Blind Cave Beetle
Glacicavicola is a genus of troglobitic (cave-dwelling) beetles in the family Leiodidae, endemic to caves in the western United States. The genus contains at least one described species, G. bathyscioides, which is completely eyeless and adapted to cold, humid cave environments with ice formations. These beetles exhibit specialized morphological adaptations for subterranean life, including elongated antennae and legs covered in fine setae for navigating difficult terrain.
Lamyctes caeculus
Lamyctes caeculus is a small lithobiomorph centipede in the family Henicopidae, first described by Brölemann in 1889. It is a cosmopolitan species with documented populations across multiple continents including South America, Australia, the Caribbean, and Africa. The species appears to thrive in human-modified environments and has been introduced to numerous oceanic islands. Its broad distribution pattern suggests anthropogenic dispersal, though some populations may represent native ranges.
Leptotyphlinae
Leptotyphlinae is a subfamily of minute rove beetles (Staphylinidae) characterized by extreme miniaturization and subterranean adaptations. Adults are eyeless, wingless, and measure less than 1.8 mm in length. The subfamily contains at least nine genera and 13 species in North America, with records from western states and Florida.
Lophognathella
Lophognathella is a genus of springtails in the family Onychiuridae, subfamily Lophognathellinae. These small, wingless hexapods are part of the euedaphic soil fauna, living primarily in deep soil layers. The genus was established by Börner in 1908 and is distributed across northern North America, the Pacific coast of North America, and the Sino-Japanese region. As members of the Onychiuridae, they lack a furcula (springing organ) and are characterized by reduced eyes and elongated mouthparts adapted for feeding in soil micropores.
Mesaphorura yosiii
Mesaphorura yosiii is a species of minute springtail in the family Tullbergiidae. First described from Japan in 1967, it has since been recorded across widely disjunct regions including desert and tropical ecosystems. The species belongs to a genus characterized by reduced or absent eyes and elongated body form. Like other members of Tullbergiidae, it inhabits soil and litter layers.
Neelipleona
Neelipleona is an order of minute hexapods within the class Collembola (springtails). Members are characterized by the complete absence of eyes, a trait distinguishing them from most other springtail groups. The group is primarily represented by the family Neelidae and includes genera such as Megalothorax and Spinaethorax. Many species exhibit troglomorphic adaptations, including elongated appendages and reduced pigmentation, associated with cave-dwelling habits. The taxonomic rank of Neelipleona remains debated, with some authorities treating it as a suborder of Symphypleona or placing it within Entomobryomorpha.
Neogoveidae
Neogoveid Harvestmen
Neogoveidae is a family of small, eyeless harvestmen (Cyphophthalmi) distributed across tropical regions of West Africa and the Neotropics. Members range from 1 to 4.5 mm in body length and exhibit distinctive morphological features including a heavily granulated dorsal scutum, laterally projecting ozophores, and variable adenostyle morphology. The family shows substantial undescribed diversity, with many species awaiting formal description.
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.
Pinodytes
Pinodytes is a genus of small, eyeless beetles in the family Leiodidae, containing at least 40 described species. These beetles are exclusively subterranean, inhabiting soil habitats where they feed on fungal material. The genus was established by Horn in 1880 and belongs to the tribe Catopocerini within the subfamily Catopocerinae. Their eyeless condition reflects complete adaptation to life in darkness.
Pinodytes gibbosus
Pinodytes gibbosus is a small, eyeless soil-dwelling beetle in the family Leiodidae. It inhabits leaf litter in California and feeds on fungi. The species was formally described in 2011, making it a relatively recent addition to the taxonomic literature. Its lack of eyes and subterranean habits reflect adaptations to a life spent primarily in dark, decomposing organic matter.
Pinodytes newelli
Pinodytes newelli is a small, eyeless beetle in the family Leiodidae. It inhabits soil environments and has been observed in Oregon and Washington. The species belongs to a genus specialized for subterranean life, with reduced visual structures.
Pinodytes newtoni
Pinodytes newtoni is an eyeless, soil-dwelling beetle in the family Leiodidae. It is a fungivore, feeding on fungal material in subterranean habitats. The species was described in 2011 and is known from North America.
Platyarthrus hoffmannseggii
Ant Woodlouse
Platyarthrus hoffmannseggii is a small, white, ant-associated woodlouse that lives exclusively in ant nests, particularly those of Lasius flavus, Lasius niger, and Myrmica species. It feeds on ant droppings and mildew within these colonies. The species is considered blind, likely an adaptation to its dark subterranean habitat. Its distribution closely tracks that of its host ants across Europe, North Africa, Turkey, and introduced populations in Australia and North America.
Platydesmida
Feather Millipedes
Platydesmida is an order of millipedes containing two families (Andrognathidae and Platydesmidae) and over 60 described species. Members are characterized by a strongly flattened body with lateral extensions (paranota) on each segment. The order is notable for containing some of the few documented examples of paternal care in arthropods, with males of certain species coiling around and guarding eggs and young. The only known fossil record consists of a specimen from mid-Cretaceous Burmese amber (~100 Ma) belonging to the extant genus Andrognathus.
Platypsyllus
beaver beetle
Platypsyllus is a monotypic genus of beetles in the family Leiodidae, subfamily Platypsyllinae. The sole species, P. castoris, is a highly specialized commensal associated exclusively with beavers. It exhibits extreme morphological adaptations including dorsoventral flattening, eyelessness, flightlessness, and modified mouthparts forming a sucking pump—features that distinguish it from all other beetles and reflect its unique lifestyle in the dense fur of its host.
Prespelea
Prespelea is a genus of minute rove beetles in the family Staphylinidae, subfamily Pselaphinae. These beetles are troglobitic, meaning they are specialized for life in cave environments. The genus was established by O. Park in 1953 and is classified within the tribe Speleobamini. Members of this genus are eyeless and exhibit morphological adaptations to subterranean habitats.
Pseudanophthalmus nelsoni
Nelson's Cave Beetle
Pseudanophthalmus nelsoni is a small, eyeless ground beetle in the family Carabidae. Described by Barr in 1965, this troglobitic species inhabits cave systems in the United States. Like other members of its genus, it exhibits adaptations to subterranean life including reduced or absent eyes and pale coloration. The species is named in honor of an individual associated with its discovery or study.
Pseudanophthalmus tenuis
Blue River cave beetle
Pseudanophthalmus tenuis is a small, eyeless ground beetle endemic to karst cave systems in Indiana, United States. Formerly considered to contain multiple subspecies, these have been elevated to full species status under Pseudanophthalmus stricticollis. The species is part of a genus specialized for subterranean life, with reduced visual structures and elongated appendages adapted to darkness.
Pycnogonum stearnsi
Stearns' sea spider
Pycnogonum stearnsi is a sea spider in the family Pycnogonidae, found on the Pacific coast of North America and in Japan. It reaches about 2.5 cm in length and lacks eyes, chelicerae, and pedipalps—unusual traits among sea spiders. It feeds by inserting its barrel-shaped proboscis into soft-bodied prey and sucking fluids. Males carry egg masses on specialized ovigerous legs.
Schaefferia
Schaefferia is a genus of springtails (Collembola: Poduromorpha: Hypogastruridae) characterized by troglomorphic adaptations in cave-dwelling species. Recent taxonomic work has described highly specialized subterranean species from Iran and Montenegro that exhibit convergent evolution of eyelessness and elaborated sensory structures. The genus demonstrates significant morphological diversification associated with subterranean habitats.
Serranillus
Serranillus is a genus of small ground beetles in the family Carabidae. The genus was established by Barr in 1995 and contains three described species, all endemic to the United States. These beetles belong to the subtribe Anillina, a group characterized by reduced eyes and elongate bodies adapted to subterranean or soil-dwelling habits. The genus is relatively poorly known, with limited ecological and biological data published.
Siro
harvestmen
Siro is a genus of cyphophthalmid harvestmen (Opiliones) in the family Sironidae. These small arachnids are characterized by their eyeless condition, elongated bodies, and association with moist microhabitats. The genus was established by Latreille in 1795 and represents one of the early-recognized lineages of the suborder Cyphophthalmi, which diverged from other harvestmen early in the evolutionary history of the order. Species in this genus are distributed primarily in the Mediterranean region and parts of Europe.
Speleonychia sengeri
Speleonychia sengeri is a troglobitic harvestman (order Opiliones) described by Briggs in 1974. The genus Speleonychia is endemic to cave systems in western North America. As a member of the family Cladonychiidae, this species belongs to a group of small, eyeless, pale-colored arachnids adapted to subterranean environments. Very few observations exist—only five records on iNaturalist—reflecting its restricted habitat and cryptic lifestyle.
Striaria
Striaria is a genus of millipedes in the family Striariidae, order Chordeumatida. The genus was established by Bollman in 1888. These small, eyeless millipedes are part of the diverse soil-dwelling fauna of temperate forests. The name Striaria is also used for a genus of brown algae (Phaeophyceae), but this represents a separate taxonomic entity in a different kingdom.
Texamaurops reddelli
Kretschmarr Cave Mold Beetle
Texamaurops reddelli is a small, eyeless cave-dwelling beetle in the family Staphylinidae, subfamily Pselaphinae. It is known from a single cave system in Texas and is one of the most narrowly distributed cave beetles in North America. The species was described in 1963 and is considered vulnerable due to its restricted range and habitat specificity. Like other pselaphine beetles, it likely feeds on fungal hyphae and organic detritus in humid cave microhabitats.