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Photos of insects and people from the Spring 2021 gathering in Louisiana, April 28-May 2

National Moth Week 2020 photos of insects and people.

Photos of insects and people from the 2019 BugGuide Gathering in Louisiana, July 25-27

Discussion, insects and people from the 2018 gathering in Virginia, July 27-29

Photos of insects and people from the 2015 gathering in Wisconsin, July 10-12

Photos of insects and people from the 2014 gathering in Virginia, June 4-7.

Photos of insects and people from the 2013 gathering in Arizona, July 25-28

Photos of insects and people from the 2012 gathering in Alabama


Genus Thermonectus

Beetle ID? Thermonectus - Thermonectus nigrofasciatus Dytiscidae -? - Thermonectus nigrofasciatus - male Dytiscidae? - Thermonectus basillaris Thermonectus basillaris (Harris) - Thermonectus basillaris 1030C03 - Thermonectus basillaris - female Sunburst Diving Beetle - Thermonectus marmoratus Thermonectus basillaris larva - Thermonectus basillaris Dytiscidae? maybe Eretes sp. - Thermonectus sibleyi
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.