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Species Chrysochus cobaltinus - Blue Milkweed Beetle

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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 Eumolpinae
Tribe Eumolpini
Genus Chrysochus
Species cobaltinus (Blue Milkweed Beetle)
Other Common Names
Cobalt Milkweed Beetle
Synonyms and other taxonomic changes
Chrysochus cobaltinus LeConte, 1857
w NA (CA-NM-MT-BC) (1)
May-Sept (BG data)
usual hosts are spp. of Milkweed (Asclepias spp., Asclepiadaceae), also reported from Oleander (2)
Life Cycle
Larvae are obligate root feeders, and adults eat the leaves of larval host plants.
Females are highly polyandrous, males engage in extended periods of post-copulatory mate guarding.
Print References
Cabrera-Mireles, H. 1998. Most Polyandrous. Pp. 89-91 In: Walker (editor) University of Florida Book of Insect Records, University of Florida, Gainesville.
Dickinson, J.L. 1995. Trade-offs between postcopulatory riding and mate location in the blue milkweed beetle. Behav. Ecol. 6: 280–286.
Dussourd, D.E., & T. Eisner. 1987. Vein-cutting behavior: insect counterploy to the latex defense of plants. Science 237: 898–901.
Peterson, M.A., S. Dobler, J. Holland, L. Tantalo, & S. Locke. 2001. Behavioral, Molecular, and Morphological Evidence for a Hybrid Zone Between Chrysochus auratus and C. cobaltinus (Coleoptera: Chrysomelidae). Annals of the Entomological Society of America, 94(1): 1-9.
Internet References
Texas Entomology - Mike Quinn, 2008
Type - MCZ, Harvard
Works Cited
1.Catalog of Leaf Beetles of America North of Mexico
Ed Riley, Shawn Clark, and Terry Seeno. 2003. Coleopterists Society.
2.Host plants of leaf beetle species occurring in the United States and Canada
Clark et al. 2004. Coleopterists Society, Special Publication no. 2, 476 pp.