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Genus Dytiscus

Predaceous Diving Beetle - Dytiscus alaskanus - female Dytiscid - Dytiscus circumcinctus - female Dytiscus alaskanus - male water beetle - Dytiscus Water Beetle - Dytiscus hatchi Big Beetle - Dytiscus fasciventris Dytiscus carolinus? - Dytiscus carolinus Unidentified Dytiscus species - Dytiscus
Classification
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
Pronunciation
dye-TISS-cuss
Explanation of Names
Dytiscus Linnaeus 1758
Greek dytikos (δυτικός) 'able to dive'
Numbers
12 spp. in our area, 26 total(1); 10 spp. in Canada(2)
Size
adults 22-40 mm, larvae up to 60 mm
Identification
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.
Range
Holarctic; throughout NA(1)
Habitat
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
Season
adults fly from March to November (varies by species)
Food
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)