Ceuthophilus

Scudder, 1862

camel crickets, cave crickets

Species Guides

33

Ceuthophilus is a of wingless orthopteran insects in the Rhaphidophoridae, commonly known as camel crickets or cave crickets. The genus contains approximately 90 and represents the most diverse group of camel crickets in North America. Members are characterized by their humpbacked appearance, extraordinarily long , and powerful hind legs adapted for jumping. They function as important components of cave and subterranean , with some species acting as trogloxenes that regularly move between cave and surface environments while others show greater cave dependence.

Ceuthophilus fossor by (c) Bob Miller, some rights reserved (CC BY), uploaded by Bob Miller. Used under a CC-BY license.Ceuthophilus mississippi by (c) Joseph McPhail, some rights reserved (CC BY), uploaded by Joseph McPhail. Used under a CC-BY license.Ceuthophilus secretus by (c) Michelle W. （鍾偉瑋）, some rights reserved (CC BY), uploaded by Michelle W. （鍾偉瑋）. Used under a CC-BY license.

Pronunciation

How to pronounce Ceuthophilus: //ˌsjuːˈθɒfɪləs//

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Identification

Distinguished from true crickets (Gryllidae) by complete absence of wings and lack of stridulatory structures for sound production. Distinguished from Asian camel crickets (Diestrammena) by subtle morphological differences and geographic origin; molecular or detailed morphological examination often required for definitive separation. Distinguished from other Rhaphidophoridae by combination of body shape, leg spination patterns, and genitalia structure. Cave-dwelling may show reduced pigmentation and size compared to surface-dwelling relatives.

Images

Appearance

Thick, dorsally arched bodies giving a humpbacked profile. is oval with long, tapering that are extraordinarily elongated relative to body size. Hind is thick and muscular, usually bearing spines in males and sometimes slightly spiny in females. are wingless. Body length ranges from 9–35 mm depending on , with legspan often exceeding body length. Coloration varies by species and , with cave-dwelling forms often paler.

Habitat

Diverse microhabitats including caves, mines, cellars, basements, rodent burrows, old wells, rock piles, stone fences, forests, and certain grasslands. Strongly associated with cool, damp, dark environments with high humidity. Some are trogloxenes that roost in caves but forage above ground, while others are more restricted cave dwellers. Surface-dwelling species occupy leaf litter, under stones and logs, and in soil crevices.

Distribution

Widely distributed across North America north of Mexico. Documented from southeastern USA, Arizona, British Columbia, California, Colorado, and throughout the continent. Center of diversity appears to be in cave-rich regions such as the Edwards Plateau of central Texas. Some show highly restricted distributions associated with specific cave systems or isolated geological features.

Seasonality

Activity patterns vary by . Cave-dwelling active year-round in stable cave environments. Surface and species show increased activity and home invasion beginning late summer and early autumn. activity predominant; often found on building exteriors at night in rural areas.

Diet

scavengers with highly generalized feeding habits. Documented food items include: decaying organic matter (leaves, roots, fruits), fungi (wild fungi, mold, mildew), dead and living insects, insect , arachnids, dead vertebrates (bats, ring-tailed cats), and various human-provided foods (oatmeal, peanut butter, molasses, bread, pet food). Some have been observed damaging paper products and fabrics, and are occasional pests in mushroom-growing operations. Will capture and consume weakened or injured .

Life Cycle

Development includes , nymph, and stages. Females use blade-like ovipositor to insert eggs into soil or substrate. Nymphs resemble smaller adults and develop through multiple instars. Specific details of developmental timing and number of instars vary among and are incompletely documented for most .

Behavior

. Highly moisture-dependent, seeking humid microhabitats. Capable of jumping several feet when disturbed—powerful hind legs allow leaps exceeding ten times body height. Exhibits thigmotaxis, traveling with body contact against walls and preferring corner junctions. Can drop legs through when captured by , with potential for . Not social in sense of eusocial insects but often aggregates in groups under boards, stones, and debris. Attracted to molasses and oatmeal baits used by entomologists for collection.

Ecological Role

Important scavengers in cave and subterranean , processing decaying organic matter and animal droppings. Serve as prey for cave-dwelling . Key trogloxenes in central Texas cave , transporting energy and nutrients between surface and cave environments. Some function as keystone for conservation and management of federally listed endangered cave arthropods.

Human Relevance

Occasional nuisance pest in basements, crawl spaces, garages, and cellars, particularly in late summer and autumn. Fecal spots can stain wood and tools in sheds. Rarely damage stored fabrics or paper products. Not dangerous to humans; cannot bite or sting despite intimidating appearance. Female ovipositor frequently mistaken for stinger. Some serve as fish . Presence indoors may indicate moisture problems or mold growth. Can be excluded by reducing humidity, sealing foundation cracks, and removing debris near buildings.

Similar Taxa

  • DiestrammenaAsian camel crickets introduced to North America; similar humpbacked appearance and preferences but becoming in eastern urban homes. Distinguished by subtle morphological features and Asian origin.
  • HadenoecusAnother North American cave cricket ; similar cave-dwelling but differs in body proportions and geographic distribution (primarily Appalachians).
  • Gryllidae (true crickets)Superficially similar orthopterans but possess wings and stridulatory apparatus for sound production, which Ceuthophilus lacks.

Misconceptions

Female ovipositor is frequently mistaken for a stinger, but the insects are harmless and cannot sting. Often called 'spider crickets' or 'sprickets' due to spider-like appearance and jumping ability, causing unnecessary fear despite being harmless. Not true crickets despite , as they lack wings and sound-producing structures.

More Details

Conservation significance

Some Ceuthophilus are considered keystone for conservation of federally listed endangered cave arthropods in Texas, serving as indicators of cave health and connectivity.

Invasion ecology

Native Ceuthophilus are being displaced by introduced Asian camel crickets (Diestrammena) in eastern North American homes, with surveys showing >90% of home-dwelling camel crickets in some areas being the introduced species.

Research methods

Traditionally collected using Hubbell's molasses traps—glass jars with diluted molasses buried to ground level, which attract specimens from surrounding .

Sources and further reading