Vicariance
Guides
Antrodiaetidae
folding-door spiders, folding trapdoor spiders, turret spiders
Antrodiaetidae is a small family of mygalomorph spiders comprising four genera and approximately 37 species. Members are commonly known as folding-door spiders or folding trapdoor spiders due to their distinctive burrow architecture: they construct silk-lined burrows with hinged, collapsible doors that fold or unfold to seal the entrance. The family is primarily distributed in the western and midwestern United States, with two relict species endemic to Japan. Antrodiaetidae are closely related to Atypidae (atypical tarantulas) and share the characteristic low dispersal ability typical of mygalomorph spiders.
Caddo agilis
Caddo agilis is a species of harvestman (Opiliones) in the family Caddidae, first described by Nathan Banks in 1892. It exhibits a disjunct distribution spanning North America and Japan, a pattern shared with its congener Caddo pepperella. Phylogenetic evidence indicates these two species diverged before acquiring their current geographic ranges, suggesting the disjunction resulted from vicariance rather than recent dispersal. The species belongs to a small family of harvestmen characterized by distinctive morphological features.
Elachistinae
grass-miner moths
Elachistinae is a subfamily of small moths in the family Elachistidae, superfamily Gelechioidea. The subfamily contains approximately 805 valid species placed in 10 genera, with the genus Elachista being the most diverse. Species are predominantly leaf miners, with larvae feeding on monocotyledonous plants, especially sedges (Cyperaceae) and grasses (Poaceae). The subfamily has a worldwide distribution with significant diversity in the Holarctic region. Many species show narrow host plant associations and some exhibit vicariant distribution patterns.
Lopidea
Scarlet Plant Bugs
Lopidea is a genus of plant bugs in the family Miridae, containing more than 90 described species. The genus belongs to the subfamily Orthotylinae and has been studied as a model for understanding speciation patterns in insects. Species in this genus show evidence of both vicariance and host plant-associated speciation. They are commonly known as scarlet plant bugs, though coloration varies among species.
Panscopus
broad-nosed weevils
Panscopus is a genus of broad-nosed weevils in the family Curculionidae, containing more than 30 described species distributed across North America. Phylogenetic studies indicate that sister species and ancestral lineages exhibit disjunct geographic distributions that correlate with geological and paleoecological events. Divergence events are estimated to have occurred between the late Eocene and Miocene, suggesting the genus originated by or before the Eocene with most cladogenesis in the middle to late Tertiary.
Parobisium
Parobisium is a genus of poorly dispersing pseudoscorpions in the family Neobisiidae. The genus exhibits a disjunct distribution pattern occurring in western North America and eastern Asia (East Asia), but is absent from Europe and central Asia. Phylogenetic evidence indicates ancient vicariance between East Asian and North American lineages rather than recent dispersal events. Many species are troglomorphic and restricted to karst cave systems.
Phellopsis
Phellopsis is a genus of zopherid beetles established by J.L. LeConte in 1862. The genus contains approximately seven recognized species distributed across North America and Asia. North American species P. obcordata and P. porcata are vicariant taxa restricted to old growth boreal forests of eastern and western North America, respectively. These species were historically confused until a 2008 revision clarified their distinct status. Asian species include P. amurensis (Russian Far East to Korea), P. suberea (Japan), P. chinense (west-central China), and P. yulongensis (Yunnan Province).
Pytho
dead log beetles, dead log bark beetles
Pytho is a small genus of saproxylic beetles in the family Pythidae, commonly known as dead log beetles or dead log bark beetles. The genus comprises approximately nine to ten described species distributed across the Holarctic region, recognized as typically boreal taxa. Species inhabit the cambial layer of dead trees, particularly conifers, where larvae feed on partially decomposed wood and bark. Several species have disjunct distributions spanning North America, Europe, and Japan, reflecting complex historical biogeographic patterns involving vicariance and dispersal across Beringia. Some species, such as P. abieticola, are considered relicts of primeval forests and are in decline across much of Central Europe.
Sabaconidae
sabaconid harvestmen
Sabaconidae is a family of harvestmen (Opiliones: Dyspnoi) comprising approximately 50 described species. The family exhibits a disjunct distribution spanning eastern North America and temperate Eurasia, with notable diversity in the southern Appalachian Mountains and the Altai Mountains of Russia. Species-level taxonomy within the family has been complicated by cryptic diversification, particularly in widespread species such as Sabacon cavicolens, which shows evidence of multiple allopatric lineages separated by vicariance and rare long-distance dispersal events.
Sciapodinae
Sciapodinae is a subfamily of long-legged flies (Dolichopodidae) distinguished by ancestral wing venation features, including a branched vein M1+2. The group exhibits high diversity in tropical and subtropical regions of the Southern Hemisphere, particularly South America, sub-Saharan Africa, the Indian subcontinent, Southeast Asia, and Australasia. Phylogeographic evidence supports a Gondwanan origin during the Early Cretaceous. The subfamily contains three tribes—Mesorhagini, Sciapodini, and Chrysosomatini—with approximately 40 genera.
Xyela
pine catkin sawflies, pine shoot gall sawflies
Xyela is a genus of primitive sawflies in the family Xyelidae, established in 1819. The genus has cosmopolitan distribution with approximately 50 described species, including both extant and fossil taxa. Most species are associated with Pinus (pine) as larval hosts, developing inside staminate cones; one species, X. gallicaulis, forms shoot galls instead. Adults are early spring fliers often found on Salix or Alnus catkins near host pines.