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Fall Fund Drive


Genus Thermonectus

Dytiscid larva - Thermonectus Thermonectus basillaris Predaceous Diving Beetle - Thermonectus basillaris - female Unknown water beetle - Thermonectus basillaris 1001C30 - Thermonectus basillaris 1001C36 - Thermonectus basillaris Beetle ID Request - Thermonectus marmoratus Dytiscid - Thermonectus basillaris
Kingdom Animalia (Animals)
Phylum Arthropoda (Arthropods)
Subphylum Hexapoda (Hexapods)
Class Insecta (Insects)
Order Coleoptera (Beetles)
Suborder Adephaga (Ground and Water Beetles)
Family Dytiscidae (Predaceous Diving Beetles)
Subfamily Dytiscinae
Tribe Aciliini
Genus Thermonectus
Explanation of Names
6 spp. in our area, ~20 total1(1)
7.5-14 mm(2)
Metatibal spurs each with apex finely emarginate (Aciliini), further, elytron densely punctate but punctures fine and inconspiciuous, AND mesofemur with hind margin setae longer than width of femur(3)
New World, mainly warm temperate to tropical; T. basilaris strays as far north as so. ON(2)
Mostly in ponds, both permanent and vernal; 2 spp. in desert streams; come to lights(2)
Life Cycle
adults reported to overwinter on land, breeding occurs in late spring to early summer, larva develop and mature quickly over the summer, especially in desert regions(2). Newly emerged adults disperse to overwintering sites in late summer and into the fall.
Works Cited
1.The Water Beetles of Florida
Epler J.H. 2010. Florida Department of Environmental Protection. Tallahassee. 414 pp.
2.Predaceous Diving Beetles (Coleoptera: Dytiscidae) of the Nearctic Region, with emphasis on the fauna of Canada and Alaska
D.J. Larson, Y. Alarie, and R.E. Roughley. 2001. NRC 43253.
3.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.