Burrow-dwelling
Guides
Ammopelmatus kelsoensis
Kelso Dunes Jerusalem Cricket, Kelso Jerusalem cricket
Ammopelmatus kelsoensis is a large, flightless orthopteran insect endemic to the Kelso Dunes of California. It belongs to the family Stenopelmatidae, commonly known as Jerusalem crickets. The species is distinguished from congeners by specific leg spine and spur characteristics, including short, spatulate apical tibial spurs and reduced ventral spines on the fore and hind tibiae. Adults are active in midsummer. The species has been collected exclusively from burrows of Rhachocnemis colonies, where it has been observed preying on nymphs of that genus.
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.
Arctosa sanctaerosae
Santa Rosa Wolf Spider
Arctosa sanctaerosae is a wolf spider endemic to the secondary dunes of white sandy beaches along the Northern Gulf Coast of the United States. The species is nocturnal and burrow-dwelling, with discrete generations. It has experienced significant habitat degradation and fragmentation due to coastal development and tourism over the last century, resulting in reduced gene flow and smaller effective population sizes across five identified population clusters. Hurricanes pose additional natural disturbance, with population recovery influenced by dune height and vegetation density.
Argasidae
soft ticks, soft-backed ticks, argasid ticks
Argasidae, commonly known as soft ticks, is one of three extant families of ticks (Ixodida), alongside Ixodidae (hard ticks) and the monotypic Nuttalliellidae. The family contains approximately 220 species in 17 genera, though taxonomic composition remains unresolved due to conflicting morphological and molecular phylogenies. Soft ticks are distinguished from hard ticks by the absence of a hard scutum (dorsal shield), a ventrally positioned gnathosoma (mouthparts-bearing structure) that is not visible from above, and rounded lateral body edges. They exhibit remarkable physiological adaptations including extreme desiccation resistance, longevity (documented up to 27 years in laboratory conditions), and the ability to survive years without feeding. Soft ticks are primarily associated with shelter habitats such as animal burrows, nests, and rock crevices, and are less commonly encountered by humans than hard ticks.
Coprophilus
Coprophilus is a genus of rove beetles (Staphylinidae: Oxytelinae) containing approximately 30–32 species. Members are restricted to temperate regions of the Northern Hemisphere and lead cryptic lifestyles in decomposing organic matter. The genus name derives from Greek roots meaning 'dung-loving', reflecting their frequent association with herbivore dung and decaying plant material. Species identification is complicated by high morphological variability and underdeveloped systematics.
Machimus polyphemi
Gopher Tortoise Robber Fly
Machimus polyphemi is a robber fly species described in 1991 that exhibits an obligate commensal relationship with gopher tortoise burrows. It is one of 12 known invertebrate species that depend entirely on burrows excavated by Gopherus polyphemus. The species is essentially endemic to longleaf pine ecosystems, particularly sandhill communities, across the southeastern United States Coastal Plain.
Nemesiidae
Tubetrapdoor and Wishbone Spiders, wishbone spiders
Nemesiidae is a family of mygalomorph spiders first described by Eugène Simon in 1889 and elevated to family status in 1985, having previously been considered part of Dipluridae. The family comprises relatively large, darkly colored spiders with elongated bodies and robust legs, commonly known as wishbone spiders due to the distinctive shape of their burrows. Members are primarily fossorial, constructing silk-lined burrows often equipped with hinged trapdoors for ambush predation. The family includes ten genera and approximately 195 species distributed across diverse habitats including coastal sands, forests, and mountainous regions on multiple continents.
Onthophagus polyphemi
gopher tortoise onthophagus beetle, onthophagus tortoise commensal scarab, Tortoise Commensal Scarab
Onthophagus polyphemi is a dung beetle species in the family Scarabaeidae. It is known for its association with gopher tortoises (Gopherus polyphemus), inhabiting their burrows in a commensal relationship. The species was described by Hubbard in 1894. Two subspecies are recognized: O. p. polyphemi and O. p. sparsisetosus.
Promyrmekiaphila clathrata
wafer-lid trapdoor spider
Promyrmekiaphila clathrata is a species of wafer-lid trapdoor spider in the family Euctenizidae, endemic to California. It constructs silk-lined burrows up to 30 cm deep in soil, covered with a wafer-like trapdoor made of silk and soil. The species exhibits deep genetic population structure across its range but is not divided into multiple species. It is one of three described species in the genus Promyrmekiaphila.
Segestriidae
Tube-dwelling spiders, Tunnel spiders
Segestriidae is a family of tube-dwelling spiders comprising two large and widespread genera (Segestria and Ariadna) and two smaller genera (Citharoceps and Gippsicola). Members are easily recognized by having six eyes arranged in a semicircle (rather than the typical eight eyes of most spiders) and the first three pairs of legs arranged forward (rather than two). These morphological features appear to be adaptations for living in silken tubes or burrows. The family has a global distribution across all continents except Antarctica, with greatest diversity in tropical and subtropical regions. The genus Ariadna alone contains 102 of the 127 described species in the family.
Tanypteryx
Dark Petaltails, Black Petaltail (for T. hageni)
Tanypteryx is a small genus of petaltail dragonflies containing two species: T. hageni (black petaltail), found in the Pacific Northwest of North America, and T. pryeri, found in Japan. The genus represents an ancient lineage that diverged from its sister species approximately 70-73 million years ago, making it an evolutionary "living fossil." T. hageni is a habitat specialist with nymphs that occupy fen wetlands and dig burrows, an uncommon life history among dragonflies.