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Species Cylas formicarius - Sweet Potato Weevil

Cylas formicarius (Fabricius) - Cylas formicarius Cylas formicarius (Fabricius) - Cylas formicarius Cylas formicarius (Fabricius) - Cylas formicarius Cylas formicarius (Fabricius) - Cylas formicarius Cylas formicarius Please help to identify.  Thanks! - Cylas formicarius Insect - Cylas formicarius Weevil - Cylas formicarius
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 Brentidae (Primitive Weevils)
Subfamily Brentinae
Tribe Cyladini (Sweet Potato Weevil)
Genus Cylas
Species formicarius (Sweet Potato Weevil)
Other Common Names
Sweet potato borer (larva)
Synonyms and other taxonomic changes
Orig. Comb: Brentus formicarius Fabricius 1798
Syn: C. elegantulus (Summers)
1 Nearctic sp.
5-6 mm

Det. M. A. Quinn, 2012
NM-FL / W. Indies / C. to S. Amer / Hawaii / Introduced from Old World (1)
Jun-Sept in TX (BG data)
sweet potato pest, also on bayhops - Ipomoea pes-caprae (Convolvulaceae) (1)
Life Cycle
Larvae bore in sweet potatoes. Tiny white eggs are laid in punctures made in vines near ground, or even in stored potatoes. Larvae burrow in and feed for 2-3 weeks, then pupate in a burrow (2).
First noted in the United States in Louisiana in 1875.
Considered invasive in this country. (Capinera, John L. North American Vegetable Pests. The Pattern of Invasion. American Entomologist. Spring 2002)
Print References
Dillon, pp. 751-752, plate 76 (3)
Papp, pp. 261-262, fig. 867 (2)
Internet References
Works Cited
1. A distributional checklist of the beetles (Coleoptera) of Florida.
Peck & Thomas. 1998. Florida Department of Agriculture and Consumer Services, Gainesville. 180 pp.
2.Introduction to North American Beetles
Charles S. Papp. 1984. Entomography Pubns.
3.A Manual of Common Beetles of Eastern North America
Dillon, Elizabeth S., and Dillon, Lawrence. 1961. Row, Peterson, and Company.