Stenopelmatidae

Burmeister, 1838

Jerusalem crickets, potato bugs, old bald-headed man, Niña de la Tierra, skull insect, sand cricket

Genus Guides

Ammopelmatus(Jerusalem crickets)

is a of large, flightless orthopterans commonly known as Jerusalem crickets or potato bugs. The family includes approximately 7 and 67 distributed across the New World (primarily North and Central America) and Old World (southern Africa, southeast Asia, and India). These insects are characterized by their wingless condition, large , and powerful . Taxonomic classification remains controversial, with ongoing debate about the placement of Old World lineages and relationships to related families such as Anostostomatidae.

Ammopelmatus by (c) Jared Shorma, some rights reserved (CC BY), uploaded by Jared Shorma. Used under a CC-BY license.

Stenopelmatidae by (c) Franco Folini, some rights reserved (CC BY). Used under a CC-BY license.

Ammopelmatus pictus 247759360 by Monica Ventrice. Used under a CC BY 4.0 license.

Pronunciation

How to pronounce Stenopelmatidae: /ˌstɛnəˌpɛlməˈtaɪdiː/

These audio files are automatically generated. While they are not always 100% accurate, they are a good starting point.

Identification

Distinguished from true crickets (Gryllidae) by the wingless condition, larger size relative to body, and spiny rather than saltatorial hind legs. Separated from and king crickets (Anostostomatidae) by geographic distribution in the New World and subtle morphological differences including tibial spine patterns and head structure. The two large spines on the inner margin of the foretibia are characteristic of certain . Males of some genera exhibit enlarged heads and , while others do not.

Images

Appearance

Large, robust orthopterans with a distinctive appearance. Most are wingless () throughout their . is large, ovoid, and often described as 'humanoid' or 'bald' in appearance. is typically shiny brown with dark stripes. Hind legs are spiny and adapted for digging rather than jumping. Body length ranges from 25-65 mm. Both juveniles and lack wings and move by crawling.

Habitat

Ground-dwelling insects found in a variety of terrestrial . In North America, commonly encountered under rocks, logs, and boards, particularly in arid and semi-arid regions. In New Zealand, tree occupy galleries in trees and under bark. Southern African have been collected from diverse habitats but specific ecological preferences remain poorly documented.

Distribution

New World: western North America west of the Rocky Mountains, Mexico, and Central America ( Stenopelmatus and Ammopelmatus). Old World: southern Africa (Sia subgenus Maxentius), southeast Asia (Sia subgenus Sia), and India (Oryctopterus).

Seasonality

activity peaks during warmer months. In North America, and nymphs are most commonly encountered from spring through fall. Specific seasonal patterns vary by region and remain undocumented for many .

Diet

, feeding on plant roots and tubers, including potatoes; also consumes dead animal matter and scavenges. Some have been observed feeding on other insects.

Life Cycle

Hemimetabolous development with , nymph, and stages. Nymphs resemble smaller versions of adults and pass through multiple instars. Both juveniles and adults are wingless. Females of at least some kill males after mating.

Behavior

, emerging at night to forage. During daytime, seeks under rocks, logs, or boards. Moves slowly by crawling. Produces sound through stridulation: in New World , by rubbing the hind leg against the side of the ; in New Zealand , by abdominal oscillation against metathoracic leg pegs. Some species drum their abdomen against the substrate to produce sound. Males of some species engage in -on fights for gallery occupancy, with harem observed in tree wetas.

Ecological Role

Important food source for birds of prey including barn owls, burrowing owls, and kestrels, particularly during winter months. Contributes to nutrient cycling through scavenging and root feeding. Serves as for hairworm (: Gordioidea) in New Zealand.

Human Relevance

Not considered agricultural pests despite occasional feeding on potato tubers. Subject of considerable mythology regarding supposed danger due to large size and formidable appearance; actually harmless aside from defensive biting if handled carelessly. Featured in educational programs and museum exhibits, including a popular t-shirt design by the Bohart Museum of Entomology. Frequently misidentified as other insects including Asian giant .

Similar Taxa

AnostostomatidaeIncludes and king crickets that closely resemble in and ; historically confused and subject to ongoing taxonomic revision. Distinguished primarily by geographic distribution (Old World vs. New World for core ) and subtle morphological features.
GryllidaeTrue crickets share general body plan but possess wings (at least in ) and have hind legs modified for jumping rather than digging, with different tibial spine arrangements.

Misconceptions

Despite suggesting danger ('potato bug', 'child of the earth'), Jerusalem crickets are essentially harmless to humans. They are frequently misidentified as venomous or as the Asian giant hornet ('murder ') in media reports. They do not cause significant agricultural damage despite occasional tuber feeding.

More Details

Taxonomic Controversy

Classification of is actively debated. Some authorities treat Old World lineages as separate or even , while morphological studies have proposed radically different arrangements including subsuming Gryllacrididae and Schizodactyloidea within Stenopelmatidae. Current consensus recognizes five tribes within a single subfamily Stenopelmatinae, but this remains provisional.

Cryptic Diversity

Recent investigations of New World have uncovered extensive cryptic biodiversity, with many undescribed species. The Stenopelmatus in particular contains numerous morphologically similar but genetically distinct .

Sound Production

Different lineages have evolved distinct sound production mechanisms. New World Stenopelmatus stridulate using leg- contact, while New Zealand use abdominal oscillation against leg pegs with different acoustic properties. Sound patterns can be species-specific and used for identification.