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Genus Tropisternus

Water Scavenger Beetle Larva - Tropisternus Predaceous Diving Beetle - Tropisternus lateralis Tropisternus lateralis Unknown larva? - Tropisternus Beetle - Tropisternus 9019912 Hydrophilid - Tropisternus Hydrophilidae - Tropisternus Unknown Aquatic Beetle - Tropisternus lateralis
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 Staphyliniformia)
Superfamily Hydrophiloidea (Water Scavenger and Clown Beetles)
Family Hydrophilidae (Water Scavenger Beetles)
Subfamily Hydrophilinae
Tribe Hydrophilini
Genus Tropisternus
Explanation of Names
Tropisternus Solier 1834
14 spp. in our area(1); 8 spp. in CA(2)
8-12 mm
Keys in (3)(4)

Backward-pointing ventral keel/spine(2):
much of NA(1); T. ellipticus occurs throughout the western states (2), T. lateralis commonly from Canada to FL, and west to the Rockies(5)
One of the first hydrophilids to be found in newly formed bodies of water, such as buckets, washtubs, etc.
Adults: algae, detritus, animal remains; larvae may be important predators of mosquito larvae in CA rice fields(2)
Print References
Spangler P.J. (1960) A revision of the genus Tropisternus (Coleoptera: Hydrophilidae) Unpubl. Ph.D. thesis. University of Missouri, Columbia. 365 pp.
Works Cited
1.American Beetles, Volume I: Archostemata, Myxophaga, Adephaga, Polyphaga: Staphyliniformia
Arnett, R.H., Jr., and M. C. Thomas. (eds.). 2000. CRC Press LLC, Boca Raton, FL.
2.Field Guide to Beetles of California
Arthur V. Evans and James N. Hogue. 2006. University of California Press.
3.The Water Beetles of Florida
Epler J.H. 2010. Florida Department of Environmental Protection. Tallahassee. 414 pp.
4.The Beetles of Northeastern North America, Vol. 1 and 2.
Downie, N.M., and R.H. Arnett. 1996. The Sandhill Crane Press, Gainesville, FL.
5.Peterson Field Guides: Beetles
Richard E. White. 1983. Houghton Mifflin Company.