Harvestman
Guides
Metasiro
Metasiro is a genus of mite harvestmen (Cyphophthalmi) in the family Neogoveidae, established by Juberthie in 1960. The genus contains three described species: M. americanus, M. sassafrasensis, and M. savannahensis. These small arachnids are part of the ancient suborder Cyphophthalmi, which represents the most basal lineage of harvestmen. Species in this genus have been documented from eastern North America.
Metasiro sassafrasensis
mite harvestman
Metasiro sassafrasensis is a species of mite harvestman (suborder Cyphophthalmi) in the family Neogoveidae. It was described in 2014 by Clouse and Wheeler. The species is known from a single locality in Grady County, North America. Like other Cyphophthalmi, it is a small, eyeless harvestman adapted to cryptic habitats.
Mitopus
Mitopus is a genus of harvestmen (Opiliones) in the family Phalangiidae, established by Thorell in 1876. The genus contains nine described species distributed across northern regions including Europe, Asia, and North America. Mitopus morio, the type species, has been subject to detailed anatomical studies including ultrastructural analysis of its photoreceptors.
Nemastoma
harvestman
Nemastoma is a genus of small harvestmen (Opiliones) in the family Nemastomatidae, first described by C.L. Koch in 1836. Species in this genus are litter-dwelling arachnids found primarily in Eurasia, with some introduced populations in North America. The genus includes species complexes with notable morphological diversity, such as the N. bidentatum complex, which exhibits extensive subspecific differentiation and parapatric distribution patterns in Slovenia. Several species have been documented as introduced to North America, including N. bimaculatum, which has established populations in Canada.
Nemastoma bimaculatum
Gold-spotted Harvestman
Nemastoma bimaculatum is a small harvestman species native to western Europe, recognized by its distinctive coloration. It has been introduced to North America, where established populations occur in Ontario, Canada. The species was first documented in North America by LeSage (1977).
Odiellus pictus
Painted Harvestman
Odiellus pictus is a species of harvestman in the family Phalangiidae, commonly known as the Painted Harvestman. It is native to North America, with documented occurrences in the northeastern United States including Vermont and Maine. The species was first described by Wood in 1868. As a member of the Phalangiidae family, it belongs to a group of long-legged arachnids that are often mistaken for spiders but are distinct in their fused body structure and single pair of eyes.
Oligolophus tridens
Three-toothed harvestman
Oligolophus tridens is a harvestman (Opiliones) in the family Phalangiidae, native to central and western Europe. It has been introduced to North America. Adults mature in summer. The species is predatory and has been documented dispersing seeds of Melampyrum.
Opilio
Opilio is a genus of harvestmen (order Opiliones, family Phalangiidae) containing over 60 described species. The genus name derives from Latin "opilio," meaning shepherd or sheep-master. These arachnids are characterized by long legs and a compact, oval body, with species distributed across the Holarctic region. The type species, Phalangium opilio, is a widespread synanthropic predator that has been introduced to North America and other regions.
Opilio parietinus
Opilio parietinus is a harvestman species native to Europe that has been introduced to North America. It was historically common on house walls in Central Europe but has been largely displaced by the invasive congener Opilio canestrinii. The species can be distinguished from O. canestrinii by dark spots on its coxae and a generally grayish-green coloration.
Opiliones
harvestmen, harvesters, daddy longlegs, granddaddy longlegs, shepherd spiders
Opiliones is an ancient order of arachnids comprising over 6,650 described species, with estimates suggesting more than 10,000 extant species worldwide. The order includes five suborders: Cyphophthalmi, Eupnoi, Dyspnoi, Laniatores, and Tetrophthalmi. Fossil evidence from 410 million-year-old Devonian deposits demonstrates that harvestmen have remained morphologically conservative since their early evolution. Despite superficial resemblance to spiders, Opiliones represent a distinct arachnid lineage with unique anatomical and behavioral characteristics.
arachnidharvestmandaddy-longlegsancient-lineageomnivorenocturnalgregariouscave-dwellingpaternal-carechemical-defenseautotomymodel-organismconservation-concernvenomlesstracheal-respirationdirect-copulationshort-range-endemictroglobiteaposematiccrypsismimicrythanatosisviscoelastic-adhesiveanurophagyvertebrate-predatorOrtholasma rugosum
Ortholasma rugosum is a species of harvestman (Opiliones) in the family Nemastomatidae, first described by Banks in 1894. It is found in North America and is one of approximately 163 observed records according to iNaturalist data. The genus Ortholasma belongs to the subfamily Ortholasmatinae, a group of small-bodied harvestmen characterized by distinctive morphological features.
Oskoron
A genus of harvestmen in the family Taracidae, established by Shear in 2016. It was erected to accommodate O. spinosus, transferred from Taracus where it had been placed by Banks in 1894, along with two newly described species from the Pacific Northwest. The genus is distinguished from Taracus by cheliceral morphology.
Oskoron spinosus
Oskoron spinosus is a harvestman (order Opiliones) and the type species of the genus Oskoron, established to accommodate this species and two close relatives distinct from the genus Taracus. Originally described as Taracus spinosus by Banks in 1894, it was later treated as Taracus malkini before being synonymized and transferred to the new genus Oskoron. It belongs to the family Taracidae within the superfamily Ischyropsalidoidea.
Paranonychus
Paranonychus is a genus of harvestmen (order Opiliones) established by Briggs in 1971. The genus contains three described species with a disjunct distribution: two species occur in the Pacific Northwest of North America, while one species is found in northern Japan. The genus is the namesake of the family Paranonychidae, which belongs to the superfamily Travunioidea. The Japanese species, P. fuscus, was originally described in a separate genus as Mutsunonychus fuscus before being transferred to Paranonychus.
Paranonychus brunneus
armoured harvestman
Paranonychus brunneus is an armoured harvestman (Order Opiliones) in the family Paranonychidae. The species was originally described as Sclerobunus brunneus by Banks in 1893 and later transferred to Paranonychus. It is found in western North America, with records from Oregon, Washington, British Columbia, and Alaska. The species belongs to the suborder Laniatores, characterized by relatively short legs and heavily sclerotized body armor.
Paroligolophus agrestis
harvestman, harvester
Paroligolophus agrestis is a small harvestman species native to Europe, including the United Kingdom. It has been introduced to North America, where established populations occur in the Pacific Northwest and Nova Scotia. The species exhibits notable sexual dimorphism in body size and possesses distinctive morphological features useful for identification.
Phalangiidae
Phalangiid Harvestmen, Harvestmen
A family of harvestmen (Opiliones: Eupnoi) containing approximately 380 described species. The family includes the widespread and well-studied Phalangium opilio, one of the most recognizable harvestmen in temperate regions. Members are characterized by long, slender legs and a fused body lacking the narrow waist seen in spiders. The family has a primarily Holarctic distribution with some representation in Africa and other regions.
Phalangioidea
harvestmen
Phalangioidea is a superfamily of harvestmen (order Opiliones) within the suborder Eupnoi, comprising five families and over 1,500 species. Members are characterized by relatively long legs, fused body regions (cephalothorax and abdomen not separated by a pedicel), and the absence of venom glands and silk production. The superfamily includes the common long-legged harvestmen frequently encountered in temperate regions. Phalangioidea is distinct from the similarly named Phalangodoidea, a superfamily within the suborder Laniatores.
Phalangium opilio
European Harvestman, Common Harvestman, Brown Harvestman, Daddy Longlegs
Phalangium opilio is the most widespread harvestman species globally, native to Europe and much of Asia and introduced to North America, North Africa, and New Zealand. It is a synanthropic species that thrives in human-modified environments including agricultural fields, gardens, and urban green spaces. The species has become a model organism for arachnid developmental biology and comparative genomics due to its ease of laboratory culture and continuous life cycle. Adults are generalist predators and scavengers that contribute to biological pest control in agricultural systems.
Phalangodes armata
Phalangodes armata is a species of harvestman (order Opiliones, suborder Laniatores) in the family Phalangodidae, described by Tellkampf in 1844. It belongs to the infraorder Grassatores, a diverse group of short-legged harvestmen characterized by their compact body form and often cryptic habits. As a member of the superfamily Phalangodoidea, this species represents one of the more derived lineages within the harvestmen, though specific natural history details remain poorly documented in available literature.
Protolophus tuberculatus
Protolophus tuberculatus is a species of harvestman (order Opiliones) in the family Protolophidae, first described by Banks in 1893. It is found in the western United States and broader North America. As a member of the Protolophidae, it represents one of the relatively small families within the suborder Eupnoi. The specific epithet "tuberculatus" refers to tuberculate (bumpy or knobby) features, likely on the body surface.
Sabacon
Sabacon is a genus of harvestmen (order Opiliones) comprising the monotypic family Sabaconidae, with approximately 59 species recognized as of 2023. Species in this genus are primarily cave-dwelling or associated with moist, sheltered habitats in temperate and boreal regions of the Northern Hemisphere. The genus exhibits a disjunct distribution pattern with centers in North America (especially the southern Appalachians), Europe (Pyrenees, Alps), and Asia (Altai Mountains, Siberia). Several species have been described recently, indicating ongoing taxonomic discovery.
Sclerobunus
harvestman
Sclerobunus is a genus of harvestmen (Opiliones: Laniatores) endemic to western North America. The genus was revised in 2014, which elevated several former subspecies to species rank, described five new species, and synonymized Cyptobunus under Sclerobunus. Species in this genus are primarily montane and show strong phylogeographic structure consistent with persistence in isolated mountain refugia during glacial cycles.
Sclerobunus idahoensis
Sclerobunus idahoensis is a species of armoured harvestman (order Opiliones) described by Briggs in 1971. Originally described as a subspecies of Sclerobunus robustus, it has since been elevated to full species status. The species belongs to the family Paranonychidae within the suborder Laniatores, a group characterized by heavily sclerotized body armor. It is known from North America, with the specific epithet suggesting an association with Idaho.
Sclerobunus robustus
Sclerobunus robustus is a montane-restricted harvestman species occurring in the southwestern United States. A 2014 taxonomic revision elevated two former subspecies (S. glorietus and S. idahoensis) to full species status. Population genomic research has identified multiple Pliocene-era refugia in the Southern Rocky Mountains and Intermontane Plateau, with genetically distinct clades showing patterns of isolation by distance in continuous mountain habitats and isolation by environment in isolated sky island populations.
Siro boyerae
mite harvestman
Siro boyerae is a species of mite harvestman in the family Sironidae. It was originally described as Neosiro boyerae by Giribet & Shear in 2010, and was previously placed in the genus Siro before taxonomic revision. This small arachnid belongs to the suborder Cyphophthalmi, a group of primitive harvestmen characterized by their eyeless condition and compact body form.
Siro exilis
Siro exilis is a species of mite harvestman (order Opiliones, suborder Cyphophthalmi) in the family Sironidae. The species was first described by Hoffman in 1963 and is currently recognized as a synonym of Neosiro exilis. It occurs in North America, with records from counties in Garrett, Giles, Mercer, Montgomery, and Pendleton. As a cyphophthalmid harvestman, it belongs to a group of small, eyeless arachnids that inhabit moist microhabitats in forested environments.
Siro kamiakensis
Siro kamiakensis is a species of mite harvestman, a small arachnid in the family Sironidae. It was described by Newell in 1943 and is currently classified under the genus Neosiro, though it was historically placed in Siro. The species is found in North America, with records from the Pacific Northwest region of the United States.
Siro sonoma
Siro sonoma is a species of mite harvestman in the family Sironidae. It was originally described by Shear in 1980 and placed in the genus Siro. In 2022, the genus Arhesiro was erected to accommodate this species and Siro clousi, with S. sonoma becoming Arhesiro sonoma. As of 2023, taxonomic sources vary in their treatment, with some recognizing Arhesiro sonoma as the accepted name while others retain Siro sonoma. The species is known only from Sonoma County, California.
Sitalcina borregoensis
Sitalcina borregoensis is a species of armoured harvestman (order Opiliones, suborder Laniatores) described by Briggs in 1968. It belongs to the family Phalangodidae, a group of small to medium-sized harvestmen characterized by well-developed body armor. The species is known from North America, with the specific epithet suggesting a connection to the Borrego region, likely in California.
Sitalcina californica
Sitalcina californica is a species of armoured harvestman in the family Phalangodidae, first described by Banks in 1893. Originally placed in the genus Sitalces, it was later transferred to Sitalcina. The species is found in North America, though specific details about its ecology and biology remain poorly documented in published literature.
Sitalcina seca
Sitalcina seca is a species of armoured harvestman described by Ubick & Briggs in 2008. It belongs to the family Phalangodidae, a group of small, often cave-dwelling or soil-associated harvestmen characterized by compact bodies and reduced eyes. The species is known from North America. As with many phalangodid harvestmen, detailed biological information remains limited.
Sitalcina sura
armoured harvestman
Sitalcina sura is a species of armoured harvestman in the family Phalangodidae, described by Briggs in 1968. It belongs to the suborder Laniatores, a diverse group of harvestmen characterized by relatively short legs and often heavily armoured bodies. The species is known to occur in North America. As with many phalangodid harvestmen, detailed ecological and behavioral information remains limited in published literature.
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.
Speleonychia
Speleonychia is a genus of armoured harvestmen (Opiliones: Laniatores) in the family Cladonychiidae, established by Briggs in 1974. The genus contains at least one described species, S. sengeri, which is endemic to Washington state in the northwestern United States. As a member of the Travunioidea superfamily, it belongs to a group of small, often cryptic harvestmen associated with moist microhabitats. The genus name suggests a cave-associated or subterranean lifestyle, though specific ecological details remain poorly documented.
Stygnomma spiniferum
armoured harvestman
Stygnomma spiniferum is an armoured harvestman in the family Stygnommatidae, first described by Packard in 1888. The species is endemic to North America. Three subspecies have been recognized: S. s. spiniferum, S. s. bolivari, and S. s. tancahense, though the taxonomic status of these subspecies varies across sources. As a member of the Laniatores, it possesses raptorial pedipalps adapted for predation.
Stygnommatidae
Stygnommatid Harvestmen
Stygnommatidae is a small family of harvestmen (Opiliones) in the infraorder Grassatores, containing approximately thirty described species. These arachnids are characterized by their compact body form, enlarged and armed pedipalps, and relatively short legs. They are primarily litter-dwelling inhabitants of Neotropical forests, with some species adapted to cave environments. The family's monophyly remains disputed among arachnologists.
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.
Taracus carmanah
Taracus carmanah is a species of harvestman (Opiliones: Ischyropsalidoidea: Taracidae) described in 2016 from Vancouver Island, British Columbia. The species name refers to Carmanah Walbran Provincial Park, a protected old-growth forest area on southwestern Vancouver Island. It was described as part of a comprehensive taxonomic revision of the genus Taracus, which included redescription of all previously named species and description of eight new species across western North America.
Taracus marchingtoni
Taracus marchingtoni is a troglobiotic harvestman species endemic to lava caves in central Oregon. First collected in 1965 but not formally described until 2016, it exhibits classic cave-adapted traits including reduced eyes and depigmentation. The species is notable for its extremely elongated chelicerae, which in males can exceed body length. It has been documented feeding on troglophilic millipedes.
Taracus packardi
Taracus packardi is a species of harvestman (Opiliones) in the family Taracidae. First described by Simon in 1879, this species occurs in North America. The taxon was revised in 2016, with Taracus nigripes Goodnight & Goodnight, 1943 synonymized with T. packardi.
Taracus pallipes
Taracus pallipes is a species of harvestman (order Opiliones) in the family Taracidae, native to western North America. The species was described by Nathan Banks in 1894. It is a relatively small, long-legged arachnid found in forested habitats. Observations and specimen records indicate a distribution centered in the Pacific Northwest region of the United States, with records from Washington and Oregon.
Taracus silvestrii
Taracus silvestrii is a species of harvestman in the family Taracidae, described by Roewer in 1929. It belongs to the suborder Dyspnoi, a group of long-legged arachnids commonly known as harvestmen or daddy longlegs. Members of the genus Taracus are characterized by their elongated body form and exceptionally long, slender legs relative to body size. The species is known from limited collection records in North America.
Taracus spesavius
Taracus spesavius is a harvestman species described in 2016 from Nevada, United States. It belongs to the family Taracidae, a group of small to medium-sized ischyropsalidoid harvestmen found in western North America. The species was established during a comprehensive revision of the genus Taracus that expanded the known distribution of the genus to include Nevada and several other western states and Canadian provinces.
Taracus taylori
Taracus taylori is a species of harvestman (Opiliones: Taracidae) described from Nevada in 2016. It belongs to the genus Taracus, a group of ischyropsalidoid harvestmen found in western North America. The species was established during a comprehensive revision of the genus that redescribed all previously named species and described multiple new species.
Taracus ubicki
A small harvestman species in the family Taracidae, described from California in 2016 as part of a major revision of the genus Taracus. The species is one of eight new Taracus species described in that work, expanding known diversity in western North American ischyropsalidoid harvestmen.
Texella bifurcata
Texella bifurcata is an armoured harvestman (order Opiliones) in the family Phalangodidae, described by Briggs in 1968. The species is known from North America. Like other members of the genus Texella, it belongs to the suborder Laniatores, characterized by relatively short legs and often cryptic habits. Very few specific details about its biology have been documented in accessible literature.
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.
Trachyrhinus marmoratus
A species of harvestman in the family Sclerosomatidae, described by Banks in 1894. As with other harvestmen in the genus Trachyrhinus, it belongs to the order Opiliones—arachnids distinct from spiders that lack fangs, venom glands, and silk production. Members of this genus are known to employ chemical defenses through repugnatorial glands.