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Home » Guide » Arthropods (Arthropoda) » Hexapods (Hexapoda) » Insects (Insecta) » Beetles (Coleoptera) » Adephaga » Predaceous Diving Beetles (Dytiscidae) » Dytiscinae

Subfamily Dytiscinae

larvae - Dytiscus Larva - Graphoderus Predaceous Diving Beetle - Thermonectus basillaris - female female diving beetle - Acilius confusus - female Predaceous diving beetle - Thermonectus intermedius - male Acilius - Acilius sylvanus Dytiscus harrisii - male What is this thing?
Classification
Kingdom Animalia (Animals)
Phylum Arthropoda (Arthropods)
Subphylum Hexapoda (Hexapods)
Class Insecta (Insects)
Order Coleoptera (Beetles)
Suborder Adephaga
Family Dytiscidae (Predaceous Diving Beetles)
Subfamily Dytiscinae
Numbers
~40 spp. in 6 genera of 4 tribes in our area, >250 spp. in 12 genera of 5 tribes total(1)
Size
8-40 mm (Nearctic species)
Identification
Adults:
Eyes unnotched at antennal bases
scutellum visible
male protarsomeres 1-3 modified to form a broad oval palette, often with suckers on the ventral surface (used to grasp the female during mating)
Larvae:
Anterior margin of the clypeus (frontoclypeus) is rounded
anteroventral margin of femur and tibia with a fringe of swimming hairs
abdominal segments 7 and 8 fringed laterally with swimming hairs
Remarks
These beetles store up toxins as a poisonous milk in the prothoracic glands. Predators are sickened and throw up the beetle. Fish that eat this beetle fall into a narcotic state.(2)
Works Cited
1.A World Catalogue of the Family Dytiscidae, or the Diving Beetles (Coleoptera, Adephaga)
Nilsson and Hajek. 2019. Distributed by authors.
2.Introduction to Ecological Biochemistry
J.B. Harborne. 1993. Academic Press Limited.
Contributed by Tim Loh on 8 February, 2009 - 1:12am
Additional contributions by v belov, Marci Hess
Last updated 7 October, 2023 - 11:19am

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