Short-range-endemic
Guides
Cryptomaster
daddy longlegs
Cryptomaster is a genus of armoured harvestmen (Opiliones) in the family Cryptomastridae, established in 1969 and containing two described species: C. leviathan and C. behemoth. Both species are endemic to the mountains of southwest Oregon and represent short-range endemic arachnids. The genus remained understudied for decades until 2016, when expanded distributional records of C. leviathan prompted discovery of the second species. These harvestmen belong to the suborder Laniatores, characterized by relatively short legs and cryptic habits in forest floor habitats.
Hypochilidae
Lampshade Spiders
Hypochilidae is an ancient and relict family of true spiders (Araneae) containing two genera: Hypochilus (11 species, North America) and Ectatosticta (22 species, Asia). The family originated in the Late Jurassic and exhibits a classic inter-continental disjunct distribution. These spiders are considered among the most primitive of araneomorphs, retaining plesiomorphic traits including two pairs of book lungs in most species. They are microhabitat specialists with naturally small geographic distributions and low vagility, making them important subjects for conservation and biogeographic research.
Hypochilus petrunkevitchi
lampshade spider
Hypochilus petrunkevitchi is a lampshade spider endemic to the southern Sierra Nevada of California. It exhibits extreme intraspecific genetic divergence, with nuclear and mitochondrial lineages corresponding directly to drainage basins. Populations show >15% CO1 divergence between river basins despite striking male morphological stasis. The species is a textbook example of a short-range endemic with naturally limited dispersal ability.
Hypochilus xomote
lampshade spider
Hypochilus xomote is a species of lampshade spider described in 2022 from the southern Sierra Nevada of California. It represents the southernmost known population of the genus Hypochilus in this mountain range and is considered a short-range endemic with an extremely restricted distribution. The specific epithet derives from the Yowlumni word for "south," reflecting its geographic position.
Leptonetidae
cave spiders
Leptonetidae is a family of small, primitive haplogyne spiders first described by Eugène Simon in 1890. The family comprises approximately 22 genera and 400 species, though taxonomic boundaries have been revised recently with elevation of Archoleptonetinae to family rank (Archoleptonetidae). Leptonetids are characterized by their small size (2-5 mm), reduced eye number, and adaptation to dark, moist microhabitats. They represent a relict fauna with origins dating to the Cretaceous period and exhibit complex biogeographic patterns across the Holarctic.
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-predatorSpirostreptida
Spirostreptida is an order of large, cylindrical millipedes containing approximately 1000 described species, making it the third largest order of millipedes. Members are characterized by their elongated bodies with 30 to 90 body rings and generally large size, including the longest known millipedes such as the giant African millipedes of genus Archispirostreptus, which may exceed 30 cm. The order is divided into two suborders, Cambalidea and Spirostreptidea, with most species occurring in tropical and subtropical regions. Spirostreptida are primarily soil-dwelling detritivores, though some species inhabit caves.
Travunioidea
travunioid harvestmen, armoured harvestmen
Travunioidea is a superfamily of armoured harvestmen (Opiliones: Laniatores) comprising four families and approximately 75-77 described species. It represents an early-diverging lineage within the suborder Laniatores, characterized by a Laurasian distribution spanning eastern Asia, eastern and western North America, and south-central Europe. Recent phylogenomic studies using ultraconserved elements (UCEs) have revised the classification, establishing the families Travuniidae, Cladonychiidae, Paranonychidae, and Cryptomastridae, while rejecting traditional tarsal claw-based taxonomy due to widespread homoplasy.