Chrysochus cobaltinus
Chrysochus cobaltinus | |
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Scientific classification | |
Kingdom: | Animalia |
Phylum: | Arthropoda |
Class: | Insecta |
Order: | Coleoptera |
Family: | Chrysomelidae |
Genus: | Chrysochus |
Species: | C. cobaltinus
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Binomial name | |
Chrysochus cobaltinus LeConte, 1857
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Synonyms[2] | |
Chrysochus cobaltinus, the cobalt milkweed beetle or blue milkweed beetle, is a member of the diverse family leaf beetles (Chrysomelidae). It occurs in the Western United States and British Columbia.
Appearance[]
C. cobaltinus has an iridescent cobalt-blue exoskeleton. Both sexes range from 6–9 millimetres (0.24–0.35 in) in length, with clubbed antenna. The elytra usually have more or less evident epipleura, changing within the varying species within the Chrysomelidae. It rarely has an exposing pygidium. The body is oval, although the ventral is not prominently convex.
Behavior[]
C. cobaltinus is similar to click beetles in being able to launch themselves a couple times the length of their body.
Both adults and larvae feed on milkweed plants. Adults typically feed on the foliage and flowers of the newly developed milkweed plant. When a large community appears, they consume a large portion of the leaf tissue from the plant, which causes significant damage to the plant. The adults eat holes in the leaves of milkweed, appearing in spring as the days become warmer and the milkweed leaves begin to develop. During the spring they disperse in large numbers on various plants within the same area of distribution.
Life cycle[]
Adults emerge in early summer and persist on milkweed plants in patches for approximately six weeks. Females are highly polyandrous; males engage in extended periods of post-copulatory mate guarding.[3]
The adult females lay their eggs on the leaves of the milkweed plants; the larva consumes the leaf tissue between the veins, leaving nothing but a skeleton. On occasion the larva also eats the root system of the plant. C. cobaltinus larvae in large numbers can consume all the plant's leaves. This apparently does not kill the plant; it goes dormant until the following year, although if the larvae consume the root system of the plant, it will eventually wither away.
Range[]
C. cobaltinus ranges in High Plains from British Columbia south through Washington, Idaho, Montana, Oregon, California, Nevada, Utah, and Colorado to Arizona and New Mexico. East of the Rocky Mountains, the species is replaced by Chrysochus auratus. Historically, the two species were considered to have allopatric distributions. Recently, at least two narrow regions in western North America have been documented where both C. auratus and C. cobaltinus occur and apparently interbreed.[4]
References[]
This article includes a list of references, related reading or external links, but its sources remain unclear because it lacks inline citations. (July 2010) |
- ^ a b c Marshall, T. A. (1864). "Corynodinorum Recensio". Zoological Journal of the Linnean Society. 8 (29): 24–50. doi:10.1111/j.1096-3642.1864.tb02004.x.
- ^ Horn, G. H. (1885). "Contributions to the Coleopterology of the United States (No 4)". Transactions of the American Entomological Society. 12: 128–162. doi:10.2307/25076454. JSTOR 25076454.
- ^ Dickinson, J. L. (1995). "Trade-offs between postcopulatory riding and mate location in the blue milkweed beetle". Behavioral Ecology. 6 (3): 280–286. doi:10.1093/beheco/6.3.280.
- ^ Peterson, M. A.; Dobler, S.; Holland, J.; T., L.; Locke, S. (2001). "Behavioral, Molecular, and Morphological Evidence for a Hybrid Zone Between Chrysochus auratus and C. cobaltinus (Coleoptera: Chrysomelidae)" (PDF). Annals of the Entomological Society of America. 94 (1): 1–10. doi:10.1603/0013-8746(2001)094[0001:BMAMEF]2.0.CO;2.
Wikimedia Commons has media related to Chrysochus cobaltinus. |
Wikispecies has information related to Chrysochus cobaltinus. |
- Texas Beetle Information
- Quinn, Mike (13 May 2017). "Species Chrysochus cobaltinus - Blue Milkweed Beetle". BugGuide. Retrieved 3 December 2019.
- The Editors of Encyclopaedia Britannica (23 April 2013). "Cobalt milkweed beetle". Encyclopaedia Britannica. Retrieved 3 December 2019.
- http://esa.confex.com/esa/2004/techprogram/paper_15339.htm
- https://web.archive.org/web/20100704170402/http://waynesword.palomar.edu/ww0502.htm
- http://www.geog.ubc.ca/biodiversity/efauna/FamiliesofColeopteraofBritishColumbia.html
- https://web.archive.org/web/20110720112837/http://share3.esd105.wednet.edu/rsandelin/fieldguide/Animalpages/Insects/Beetles.htm
- http://www.buzzle.com/articles/types-of-beetles.html
- Eumolpinae
- Beetles of North America
- Beetles described in 1857
- Taxa named by John Lawrence LeConte