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For Insects, Spiders & Their Kin
For the United States & Canada
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Upcoming Events

Photos of insects and people from the 2022 BugGuide gathering in New Mexico, July 20-24

National Moth Week was July 23-31, 2022! See moth submissions.

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

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

Photos of 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

Previous events


Genus Hydaticus

Predacious Diving Beetle - Hydaticus cinctipennis Predaceous Diving Beetle - Hydaticus aruspex - female Predacious Diving Beetle - Hydaticus aruspex Predaceous Diving Beetle - Hydaticus bimarginatus Prodaticus bimarginatus - Hydaticus bimarginatus Predaceous Diving Beetle - Hydaticus bimarginatus - male Dytiscid - Hydaticus aruspex Unknown Dytiscid - Hydaticus bimarginatus
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 Hydaticini
Genus Hydaticus
Explanation of Names
Hydaticus Leach (1817)
5 spp. in our area, at least 150 spp. total
11-15.4 mm(1)
Key to NA species in Larson et al. (2001)(1)
holarctic: 4 spp. in e. NA, H. aruspex is holarctic (transcontinental in NA)(2)(3)
Densely vegetated areas of ponds and eutrophic lakes(1)
all year round but most adults encountered from spring through fall
Life Cycle
Northern species generally overwinter as adults and mate in the spring; larvae complete development by early summer and emergent adults disperse to overwintering sites later in the season(1)
See Also