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Species Megacerus discoidus

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Kingdom Animalia (Animals)
Phylum Arthropoda (Arthropods)
Subphylum Hexapoda (Hexapods)
Class Insecta (Insects)
Order Coleoptera (Beetles)
Suborder Polyphaga (Water, Rove, Scarab, Long-horned, Leaf and Snout Beetles)
No Taxon (Series Cucujiformia)
Superfamily Chrysomeloidea (Long-horned and Leaf Beetles)
Family Chrysomelidae (Leaf Beetles)
Subfamily Bruchinae (Pea and Bean Weevils)
Tribe Bruchini
Genus Megacerus (Large-horned Bruchids)
Species discoidus (Megacerus discoidus)
Other Common Names
Red Megacerus
Synonyms and other taxonomic changes
Megacerus discoidus (Say)
Orig. Comb: Bruchus discoidus Say 1824
Often mis-spelled as discoideus, an error begun by Melsheimer in 1853.
9 spp. n. of Mex. (1)
Body length 2.6–3.6 mm (Kingsolver 2004)
This handsome species with its quadrate, red elytral maculae can hardly be mistaken for any other eastern American bruchid. (2)
e NA to BC (NM-FL-NB-BC) (2)
Host plants: Calystegia spp.; Convolvulus arvensis; Ipomoea spp. Flowers of Daucus carota and Hibiscus sp.(2)
Life Cycle
Adults are commonly found on flowers of many plant species. Natural enemies: Uscana semifumipennis; Dinarmus sp.(2)
Print References
Wang, R. & L.T. Kok. 1983. Synchronization of Megacerus discoidus with the hedge bindweed Calystegia sepium, in southwestern Virginia. Virginia Journal of Science 34: 109.
Wang, R. & L.T. Kok. 1986a. Life history of Megacerus discoidus (Coleoptera: Bruchidae), a seedfeeder of hedge bindweed, in Southwestern Virginia. Annals of the Entomological Society of America, 79(2): 359-363.
Wang, R. & L.T. Kok. 1986b. Host specificity of Megacerus discoidus (Coleoptera: Bruchidae) and its impact on hedge bindweed, Calystegia sepium. Environmental Entomology 15: 834–838.
Works Cited
1.American Beetles, Volume II: Polyphaga: Scarabaeoidea through Curculionoidea
Arnett, R.H., Jr., M. C. Thomas, P. E. Skelley and J. H. Frank. (eds.). 2002. CRC Press LLC, Boca Raton, FL.
2.Handbook of the Bruchidae of the United States and Canada
Kingsolver J.M. 2004. USDA, Technical Bulletin 1912 (2 vols.).