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Species Rhyssomatus lineaticollis - Milkweed Stem Weevil

Another milkweed weevil - Rhyssomatus lineaticollis Weevil - Rhyssomatus lineaticollis Rhyssomatus lineaticollis dark weevil - Rhyssomatus lineaticollis  Milkweed Stem Weevil (Rhyssomatus lineaticollis) - Rhyssomatus lineaticollis Rhyssomatus lineaticollis Withering, clasping milkweed - Rhyssomatus lineaticollis Weevil - Rhyssomatus lineaticollis
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 Curculionoidea (Snout and Bark Beetles)
Family Curculionidae (Snout and Bark Beetles)
Subfamily Molytinae
Genus Rhyssomatus
Species lineaticollis (Milkweed Stem Weevil)
Synonyms and other taxonomic changes
Rhyssomatus lineaticollis (Say)
Orig. Comb: Rhynchaenus lineaticollis Say 1824
n. of KS to VA (BG data), but recorded through the se US (1)
primarily feeds on the stems of A. syriaca.
Life Cycle
Adults initially feed on the apical leaves and then, after feeding, female weevils walk to lower parts of the stem and chew several sequential holes in the stem, creating a continuous scar. Females lay a single egg per hole and larvae complete development inside the stem while feeding on pith tissue. Oviposition scar length is an accurate predictor of the number of eggs laid by the adult female. (Agrawal, 2005)
Print References
Agrawal, A.A. 2005. Natural selection on common milkweed (Asclepias syriaca) by a community of specialized insect herbivores. Evolutionary Ecology Research, 7: 651–667.
Agrawal, A.A. & P.A. Van Zandt. 2003. Ecological play in the coevolutionary theater: Genetic and environmental determinants of attack by a specialist weevil on milkweed. Journal of Ecology 91: 1049-1059.
Fordyce, J.A. & S.B. Malcolm. 2000. Specialist weevil, Rhyssomatus lineaticollis, does not spatially avoid cardenolide defenses of common milkweed by ovipositing into pith tissue. Journal of Chemical Ecology, 26: 2857–2874.
Nishio, S., Blum, M.S., Takahashi, S. 1983. Intraplant distribution of cardenolides in Asclepias humistrata (Asclepiadaceae), with additional notes on their fates in Tetraopes melanurus (Coleoptera: Cerambycidae) and Rhyssomatus lineaticollis (Coleoptera: Curculionidae). Memoirs of the College of Agriculture, Kyoto University 122:43-52.
St. Pierre, M. and S.D. Hendrix. 2003. Movement patterns of Rhyssomatus lineaticollis Say (Coleoptera: Curculionidae) within and among patches (Asclepiadaceae) patches in fragmented landscapes. Ecological Entomology 28: 579-586.
Internet References
Texas Entomology - Mike Quinn, 2009