Gryllus assimilis

(Fabricius, 1775)

Jamaican field cricket, silent cricket (misnomer)

Gryllus assimilis, the Jamaican , is a field cricket to the West Indies, southern United States, Mexico, and parts of South America. It is distinguished from similar species primarily by its song: a short, pulsed chirp with rapid pulse rate and brief intervals between pulses, creating a nearly continuous sound. Since 2010, it has become widely bred as a feeder for the pet industry throughout North America and Europe, largely replacing the house (Acheta domesticus) after that species was devastated by cricket paralysis virus. The species is notable for its to this virus, its relatively docile compared to some other Gryllus species used in the pet trade, and its status as a USDA-approved native species for commercial sale in the United States.

Gryllus assimilis by (c) Andre Hosper, some rights reserved (CC BY), uploaded by Andre Hosper. Used under a CC-BY license.

Gryllus assimilis by (c) Sam Kieschnick, some rights reserved (CC BY), uploaded by Sam Kieschnick. Used under a CC-BY license.

Snodgrass Gryllus assimilis by R. E. Snodgrass. Used under a Public domain license.

Pronunciation

How to pronounce Gryllus assimilis: //ˈɡrɪl.lʊs əˈsɪm.ɪ.lɪs//

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

Identification

Distinguished from similar North by male song characteristics: a short, pulsed chirp emitted at approximately one-second intervals, with rapid pulse rate and brief intervals between pulses producing a nearly continuous sound. Historically confused with other eastern U.S. field crickets until B.B. Fulton's 1932 work demonstrated that morphologically identical produced different songs and had non-overlapping seasonal cycles. Differs from Gryllus locorojo ('crazy red' or 'banana ') in lacking the reddish- coloration with three or four longitudinal stripes characteristic of that . Two recognized: G. a. assimilis (West Indies, United States, Mexico, South America) and G. a. pallida (Mexico).

Images

Habitat

Weedy fields, roadside verges, lawns, and rough pasture. In the United States, restricted to Florida and southern Texas within its range.

Distribution

to the West Indies ( locality Jamaica), southern United States (Florida, southern Texas), Mexico, and South America (Ecuador, Peru, Bolivia, Paraguay, northern Argentina). Commercially available throughout North America and Europe due to widespread breeding programs since 2010.

Life Cycle

Females up to 400 via into damp soil. Eggs hatch in approximately eleven days at temperatures between 25°C and 30°C. Nymphal development requires six to seven weeks before reaching sexual maturity. have been observed to cannibalize eggs when searching soil for food.

Behavior

Males produce -specific calling songs to attract females. Males engage in aggressive interactions involving chirping, snapping, and foreleg grappling when competing for mates or territory. Females select mates based on song quality and may assess male dancing displays.

Ecological Role

Serves as a bioindicator for assessing environmental quality in -impacted due to demonstrated sensitivity to glyphosate-based exposure.

Human Relevance

Widely bred as a feeder for the pet industry since 2010, having become the primary replacement for the house (Acheta domesticus) after that was devastated by cricket paralysis virus (AdDNV). Considered a pest in vegetable and flower gardens and citrus nurseries; historically controlled by with calcium cyanide. Subject to commercial trade regulations: USDA-approved for sale in the United States due to status, unlike non-native alternatives such as Gryllus bimaculatus.

Similar Taxa

Gryllus locorojoOften confused in commercial trade and misidentified as G. assimilis in Russia and Europe; distinguished by reddish- with three to four longitudinal stripes and different song, described as new in 2012
Gryllus bimaculatusEuropean also used as feeder replacement; non- to North America and illegal to sell in the United States, whereas G. assimilis is native and USDA-approved
Acheta domesticusCommon house formerly in pet trade; replaced by G. assimilis due to susceptibility to cricket paralysis virus, which G. assimilis resists
Gryllus pennsylvanicusNorth fall with which G. assimilis was historically confused; distinguished by different song and seasonal activity patterns, as demonstrated by Fulton's 1932 work

Misconceptions

The 'silent ' is a misnomer; males produce a distinct, audible song. Historical confusion with other eastern U.S. led to G. assimilis being treated as a single widespread before Fulton's research revealed a complex of eight cryptic species distinguishable primarily by song.