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Genus Hydrophilus - Giant Water Scavenger Beetles

Hydrophilus triangularis - Hydrophilus ovatus Predatory Aquatic Beetle Larva - Hydrophilus Hydrophilus triangularis perhaps, dorsal - Hydrophilus triangularis Hydrophilus triangularis 9050490 Hydro - Hydrophilus ovatus 9049431,4 Hydrophilus - Hydrophilus Giant Scavenger Beetle_Hydrophilus triangularis? - Hydrophilus Male, Hydrophilus triangularis? - Hydrophilus triangularis
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)
Explanation of Names
Hydrophilus Geoffroy 1762
Greek 'water-loving'
3 spp. (in 2 subgenera) in our area(1); additional species may be expected in so. FL; 3 subgenera total(2)
the largest members of the family, >30 mm (our spp. up to 40 mm, extralimital spp. up to ~50 mm)(2)(3)
key to spp. in Epler (2010)(2)
widespread N. Amer. & Eurasia(1)(3)
stagnant/slow waters; prefer deeper water (weedy ponds, deep drainage ditches)(2)
Life Cycle
Female deposits up to 140 yellow eggs in cocoon-like egg case with a "mast". Case is large, about 15 X 24 mm, and floats or is attached to an underwater object. Larvae aquatic, predatory? Pupation occurs in moist soil. Adults emerge in under two weeks and return to the water. There are one or two generations per year. Some adults overwinter on land, under leaf litter. Others may remain under ice of ponds and stay active all winter. Lifespan may exceed one year.
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.Keys to the insects of the Far East of the USSR, Vol. 3. Coleoptera I
Lehr P.A., ed. 1989. Leningrad, Nauka Publishing House, 572 pp.