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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

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Genus Dytiscus

large Predacious Diving Beetle - Dytiscus verticalis Monster! - Dytiscus Dytiscid larva - Dytiscus Dytiscus verticalis? - Dytiscus verticalis Predaceous Diving Beetle - Dytiscus harrisii Dytiscidae: Dytiscus - Dytiscus harrisii Near Lake Padden - Dytiscus predaceous diving beetle - Dytiscus carolinus - male
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
Genus Dytiscus
Explanation of Names
Dytiscus Linnaeus 1758
Greek dytikos (δυτικός) 'able to dive'
12 spp. in our area, 26 total(1); 10 spp. in Canada(2)
adults 22-40 mm, larvae up to 60 mm
Pronotum with or without pale borders. Elytra usually bordered with yellow. Pronotum and/or elytra of female variably smooth or grooved. Metatibiae much longer than broad, outer apical spur very thin. Protarsi of male have two large disks (and small disks) used to grasp female during mating. Hind legs move synchronously while swimming; adults often attracted to light.
Larvae with prominent cerci and dense lateral fringes of hair on the last 2 abdominal segments and cerci. The anterior portion of the head is rounded.
Holarctic; throughout NA(1)
permanent or temporary freshwater ponds and pools (D. marginicollis may occur in saline ponds), plus streams and rivers; usually found on or among aquatic plants
adults fly from March to November (varies by species)
fish larvae, mosquito larvae, other aquatic invertebrates, sometimes tadpoles and salamanders
Life Cycle
one generation per year; mating occurs in late fall and/or early spring; eggs injected singly into underwater plant stems; fully-grown larvae creep out of water and pupate in moist earth, then emerge as adults in about a week and return to water; overwinters as an adult in permanent waters (D. hybridus may overwinter on land)
Print References
Roughley, R. E. 1990. A systematic revision of species of Dytiscus Linnaeus (Coleoptera: Dytiscidae). Part 1. Classification based on adult stage. Quaestiones Entomologicae 26: 383-557.