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Genus Tropisternus

Water Scavenger Beetle - Tropisternus collaris Tropisternus lateralis marginatus - Tropisternus lateralis Diving Beetle - Tropisternus Tropisternus lateralis larva? - Tropisternus Water coleoptera - Tropisternus Tropisternus collaris? - Tropisternus collaris Tropisternus quadristriatus - female Beetle ID - Tropisternus
Kingdom Animalia (Animals)
Phylum Arthropoda (Arthropods)
Subphylum Hexapoda (Hexapods)
Class Insecta (Insects)
Order Coleoptera (Beetles)
Suborder Polyphaga
No Taxon (Series Staphyliniformia)
Superfamily Hydrophiloidea
Family Hydrophilidae (Water Scavenger Beetles)
Subfamily Hydrophilinae
Tribe Hydrophilini
Genus Tropisternus
Synonyms and other taxonomic changes
revised in (1)
Explanation of Names
Tropisternus Solier 1834
14 spp. in US(2), with 7 reaching Canada

Tropisternus affinis
Tropisternus apicipalpis
Tropisternus blatchleyi
Tropisternus californicus - CA, OR, Mexico (Baja California)
Tropisternus collaris
Tropisternus columbianus
Tropisternus fuscitarsis - CA, NV to Columbia
Tropisternus glaber
Tropisternus lateralis
Tropisternus mixtus
Tropisternus natator
Tropisternus orvus - CA, NV, OR
Tropisternus quadristriatus
Tropisternus sublaevis
8-15 mm
Keys in (1)(3)(4)
most of the Americas
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(5)
Works Cited
1.A revision of the genus Tropisternus (Coleoptera: Hydrophilidae)
Spangler P.J. 1960. Unpubl. Ph.D. thesis. U. Missouri, Columbia. 365 pp.
2.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.
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.Field Guide to Beetles of California
Arthur V. Evans and James N. Hogue. 2006. University of California Press.