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Species Trirhabda geminata

Encelia Leaf Beetle  -- larva - Trirhabda geminata Leaf beetle - Trirhabda geminata Blister Beetle? - Trirhabda geminata Is this Trirhabda geminata? - Trirhabda geminata Leaf Beetle on Encelia - Trirhabda geminata Beetle - Trirhabda geminata Reality check: Trirhabda geminata? - Trirhabda geminata Trirhabda? - Trirhabda geminata
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 Galerucinae (Skeletonizing Leaf Beetles and Flea Beetles)
Tribe Galerucini
No Taxon (Section Coelomerites)
Genus Trirhabda
Species geminata (Trirhabda geminata)
Explanation of Names
Trirhabda geminata Horn 1893
CA-TX, CO (1)
Dry chaparral, desert scrub, and coastal sage scrub, where Encelia (Brittlebush) occurs.
Larval host plants are species of Encelia.
In the inland desert portions of the range of T. geminata, the host species are E. farinosa, E. virginensis(1).
In coastal adjacent southern California, E. californica is the host plant...which seems to often be overlooked in many references, but is mentioned in in O'Brien & Atsatt (1982) [at bottom of 1st page] and corroborated by many BugGuide posts.
A photo of this species can be found in Evans & Hogue (2) (see Plate 272).
Print References
Blake D.H. (1931) Revision of the species of beetles of the genus Trirhabda north of Mexico. Proc. U.S. Nat. Mus. 79(2):1-36 (Full text)
Blake D.H. (1951) New species of chrysomelid beetles of the genera Trirhabda and Disonycha. Journal of the Washington Academy of Sciences, 41:324-328. (Full text)
Hogue S.M. (1970) Biosystematics of the genus Trirhabda LeConte of America north of Mexico (Chrysomelidae: Coleoptera). Ph.D. dissertation, University of Idaho, 212 pp.(1) The most complete reference to date.
Kunze, A., Aregullin, M., Rodriguez, E., & Proksch, P. (1996). Fate of the chromene encecalin in the interaction of Encelia farinosa and its specialized herbivore Trirhabda geminata. J. Chem. Ecol. 22:3, 491-498. (Abstract).
Sorensen, M. A., J. A. Bethke, and R. A. Redak (2010). Potential Host Plants of Trirhabda geminata (Coleoptera: Chrysomelidae) : Impacts on Survival, Development, and Feeding. Environmental Entomology 39(1):159-163. Abstract
O'Brien, P. Y. & P. R. Atsatt. (1982). Life history and general bionomics of Trirhabda sericotrachlya Blake (Coleoptera: Chrysomelidae) in southern California. Pan-Pacific Entomologist 58 (2) 139-152. (Full text)
Internet References
Works Cited
1.Biosystematics of the genus Trirhabda LeConte of America north of Mexico (Chrysomelidae: Coleoptera)
Steve Munroe Hogue. 1970. Ph.D. dissertation, University of Idaho, 212 pp.
2.Field Guide to Beetles of California
Arthur V. Evans and James N. Hogue. 2006. University of California Press.