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Species Hydrophilus triangularis - Giant Black Water Beetle

unknown diving beetle? near temporary pool - Hydrophilus triangularis Bug (deceased) - Hydrophilus triangularis Bug (deceased) - Hydrophilus triangularis Unknown large water beetle. - Hydrophilus triangularis Hydrophilus triangularis - Giant Black Water Beetle? - Hydrophilus triangularis - female Texas SE Gulf Coast - Hydrophilus? - Hydrophilus triangularis Giant Black Water Beetle? - Hydrophilus triangularis - male Giant Black Water Beetle? - Hydrophilus triangularis - female
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 Hydrophilus (Giant Water Scavenger Beetles)
Species triangularis (Giant Black Water Beetle)
Other Common Names
Giant Diving Scavenger Beetle, Giant Water Scavenger
Synonyms and other taxonomic changes
Hydrophilus triangularis Say 1823
3 spp. (in 2 subgenera) n. of Mex. (1)
32-40 mm (2)
Similar to the usually smaller and less oblong H. (Dibolocelus) ovatus (which is more common southward), but the prosternum is undivided (entire) (2)

H. triangularis Say
widely dist. (CA-FL-QC-BC) (3),(4) (less common in nw. N. Amer.)
recorded from marshy lakes, weedy ponds, swales and streams, but most likely found under the lights of a parking lot (2)
April-August in SC
predator/herbivore (Moorhead et al. 1998)
Comes to lights
Print References
Moorhead, D.L., D.L. Hall and M.R. Willig. 1998. Succession of macroinvertebrates in playas of the southern High Plains, USA. JNABS 17(4): 430-442.
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.The Water Beetles of Florida
Epler J.H. 2010. Florida Department of Environmental Protection. Tallahassee. 414 pp.
3. A distributional checklist of the beetles (Coleoptera) of Florida.
Peck & Thomas. 1998. Florida Department of Agriculture and Consumer Services, Gainesville. 180 pp.
4.Review of the Family Hydrophilidae of Canada and Alaska
Ales Smetana. 1988. Entomological Society of Canada.