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Species Pachybrachis obsoletus

casebearer - Pachybrachis obsoletus Case-bearing Leaf Beetle - Pachybrachis obsoletus Pachybrachis obsoletus Suffrian - Pachybrachis obsoletus Pachybrachis obsoletus Suffrian - Pachybrachis obsoletus Pachybrachis obsoletus Pachybrachis obsoletus Pachybrachis obsoletus Beetle, anterior - Pachybrachis obsoletus
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 Cryptocephalinae (Case-bearing Leaf Beetles)
Tribe Cryptocephalini
Subtribe Pachybrachina
Genus Pachybrachis (Scriptured Leaf Beetles)
Species obsoletus (Pachybrachis obsoletus)
Explanation of Names
Pachybrachis obsoletus Suffrian, 1852
Length 2.3-3.5 mm (1)
Yellow, strongly marked with black, varying to nearly completely yellow with brown maculations.
Head yellow with vertex black or brown, frons with or without median black vitta; strongly punctate.

Pronotum yellow with black M varying to orange-yellow with 3 basal and 2 discal light brown spots; punctures usually somewhat larger than elytral punctation.

Elytral maculation somewhat resembling that of P. tridens, but not nearly so sharply outlined: a subcordate spot behind scutellum, paired subapical spots, and 3 marginal spots on each elytron. Varies from strongly black to nearly completely yellow. Two large calli, about half as long as elytra, present from 2nd striae mesad.
Pygidium black basally, with lateral edges of abdomen yellow.

Legs yellow, femora sometimes with dark mid area. (1)
widely dist. outside of sw US (NM-FL-NB-BC) (2)(3)
reported from a variety of plant families (4)
See Also
Very similar to tridens (5)
Works Cited
1.The leaf beetles of Alabama
Edward Balsbaugh and Kirby Hays. 1972. Agricultural Experiment Station, Auburn University.
2.Catalog of Leaf Beetles of America North of Mexico
Ed Riley, Shawn Clark, and Terry Seeno. 2003. Coleopterists Society.
3.Pachybrachis (Coleoptera, Chrysomelidae, Cryptocephalinae) of eastern Canada
Barney et al. 2013. ZooKeys 332: 95–175.
4.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.
5.A revision of the North American species of Pachybrachys
H. C. Fall. 1915. Transactions of the American Entomological Society, Vol. 41, No. 3: 291–486 .