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Whiteara356/sandbox
Scientific classification
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G. veletis
Binomial name
Gryllus veletis
Alexander & Bigelow, 1960

Gryllus veletis, commonly known as the spring field cricket, is abundant throughout eastern North America. G. veletis is a solitary, aggressive, burrow-inhabiting species of field cricket. This species is commonly confused with Gryllus pennsylvanicus (fall field cricket), as they inhabit the same geographical area. However, the two species are easily distinguished through examination of life history, ovipositor and behavioural differences.[1]

Identification[edit]

Adult body length measures approximately 22.0 mm (0.87 inches).[1] Males of this species are black with dark brown or black appendages.[1] Females are similar in colour and have a dark brown ovipositor, measuring approximately 14 mm (0.55 inches).[1] Females differ from male colour as they have lighter, more reddish legs.[1]

Natural history[edit]

Distribution[edit]

Gryllus veletis is abundant throughout eastern North America.[1] It ranges from southern Canada to northern Georgia, and as far west as Washington and Oregon[1] G. veletis occurs in the same areas as G. pennsylvanicus but the spring field cricket does not reach as far north as Nova Scotia, Canada.[1] G. veletis can be found in disturbed habitats such as old fields, and weedy roadsides.[2]

Life cycle and mating behaviour[edit]

Spring field crickets are sexually mature from late May to early August.[3] Males of the species attract sexually receptive females by acoustic signals, known as stridulation.[4] This process occurs by rubbing two rigid veins on the wings against one another. One vein is a scraper (smooth surface), the other a file (rough surface). The wings are held at a 45 degree angle above the thorax to amplify the sound.[5] Calling tends to peak at sunrise[6] and lasts between 1.3 to 1.8 hours per night.[3] However, if nighttime temperatures drop below 10 °C (50 °F), calling will switch to the daytime.[6] At 29°C (85°F), the cricket will call at 120–370 chirps per minute, in a series of 3 to 5-pulse chirps.[1] When a female is within the vicinity of a male’s territory, a quieter song (known as a courtship song) is used to reduce the risk of predation and attraction of male competitors.[4] Both males and females have directional hearing. Tympanums on the front legs pick up the vibrations created by the chirps. Depending on the strength, and on which leg the vibration is received, the location of the caller can be determined.[7]

Once mating occurs, females lay eggs, which mature between June and September.[8] The spring field cricket will continue to develop into late-instar nymphs and overwinter in this stage until emergence as adults in late May.[2][8] G. veletis therefore undergoes one generation per year.[9]

Human Impact[edit]

Spring field crickets are often grouped with the other species of field crickets when discussing their possible impacts on humans.

Field crickets will invade a home due to attraction to the light or to seek refuge from poor weather. Entrance can be gained through small cracks and crevices leading into a building. Once inside, damage to nylon, wool, plastic and leather fabrics may occur. The human inhabitant can also be aggravated by the field cricket's nocturnal chirping. However, unlike house crickets (Acheta domesticus), field crickets are not able to adapt to a residential environment due to constraints in their life history traits and consequently, the insect will not live through the winter.[10]

References[edit]

  1. ^ a b c d e f g h i Alexander, R. D. & R. S. Bigelow (1960). "Allochronic speciation in field crickets, and a new species, Acheta veletis" (PDF). Evolution. 14: 334–346.
  2. ^ a b Zuk, M. (1987). "Seasonal and individual variation in gregarine parasite levels in field crickets Gryllus veletis and G. pennsylvanicus" (PDF). Ecological Entomology. 12: 341–348. doi:10.1111/j.1365-2311.1987.tb01013.x.
  3. ^ a b French, B. W. & W. H. Cade (1988). "Sexual selection at varying population densities in male field crickets, Gryllus veletis and G. pennsylvanicus". Journal of Insect Behavior. 2: 105–121. doi:10.1007/BF01053621.
  4. ^ a b Burpee, D. M. & S. K. Sakaluk (1993). "The effect of pair formation on diel calling patterns of two cricket species, Gryllus veletis and Gryllodes sigillatus (Orthoptera: Gryllidae)". Journal of Insect Behavior. 6: 431–440.
  5. ^ Bigelow, R.S. 1964. Song Differences in Closely Related Cricket Species and Their Significance. The Australian Journal of Science,4:27
  6. ^ a b French, B. W. & W. H. Cade (1987). "The timing of calling, movement, and mating in the field crickets Gryllus veletis, G. pennsylvanicus, and G. integer". Behavioural Ecology and Sociobiology. 21: 157–162. doi:10.1007/BF00303205.
  7. ^ Hill, K.G.; Boyan, G.S. 1976. Directional Hearing in Crickets. Nature,262: 390- 391
  8. ^ a b "Life cycles of seven Gryllus species". Retrieved 2009-02-04.
  9. ^ Alexander, R. D. (1968). "Life cycle origins, speciation, and related phenomena in crickets". The Quarterly Review of Biology. 43: 1–41. doi:10.1086/405628.
  10. ^ "Ebeling, W. Urban Entomology Chapter 12: Miscellaneous Pests. UC Riverside". Retrieved 2009-02-20.

Category:Crickets Category:Insects of North America Category:Animals described in 1960