Identification, Images, & Information
For Insects, Spiders & Their Kin
For the United States & Canada
 

Register · Log In
HomeGuideID RequestRecentFrassForumsDonateHelp
Clickable Guide
Moths Butterflies Flies Caterpillars Flies Dragonflies Flies Mantids Cockroaches Bees and Wasps Walkingsticks Earwigs Ants Termites Hoppers and Kin Hoppers and Kin Beetles True Bugs Fleas Grasshoppers and Kin Ticks Spiders Scorpions Centipedes Millipedes

Calendar
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
TaxonomyBrowse
Info
ImagesLinksBooksData
Home » Guide » Arthropods (Arthropoda) » Hexapods (Hexapoda) » Insects (Insecta) » Beetles (Coleoptera) » Ground and Water Beetles (Adephaga) » Predaceous Diving Beetles (Dytiscidae) » Dytiscinae » Aciliini » Acilius

Genus Acilius

Classification · Synonyms and other taxonomic changes · Explanation of Names · Numbers · Size · Identification · Range · Habitat · Season · Life Cycle · Remarks · Works Cited
Diving beetle - Acilius mediatus Dytiscid - Acilius abbreviatus - female Water Beetle - Acilius abbreviatus Water Beetle - Acilius abbreviatus Predaceous diving beetle - Acilius abbreviatus - male Acilius mediatus? - Acilius mediatus Predaceous diving beetle - Acilius abbreviatus - male - female Acilius larva? - Acilius
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
Tribe Aciliini
Genus Acilius
Synonyms and other taxonomic changes
revised in (1)
Explanation of Names
Acilius Leach 1817
Numbers
7 spp. in our area, 13 total(2)(1)
Size
adult 10-16 mm, larva 15-30 mm
Identification
Adult: top of head yellowish with two dark transverse bands, the anterior band undulate or shaped like an M or upside-down W; pronotum yellowish with two dark transverse bands on disc, not terminally, as in Graphoderus; notched spur on hind tibia; elytral mottling or speckling less pronounced than in Graphoderus; elytra punctate (and longitudinally sulcate in female)
Larva: swimming hairs present on last two abdominal segments; ligula (structure located between the maxillary palps) is deeply bifid (2-pronged).
in Graphoderus elytra more heavily mottled/speckled, and dark transverse pronotal bands located apically
key to spp. in (1)
Range
Holarctic, widespread (including the arctic)(1)
Habitat
submergent vegetation
Season
Year-round with adults most frequently encountered in spring during mating season and late summer when they disperse to overwintering sites
Life Cycle
Adults have been reported to overwinter in permanent water bodies and disperse to breeding sites during spring; larvae complete development later in the spring and into the early summer; newly emerged adults disperse to overwintering sites later in the summer and into the fall(3)
Remarks
Acilius confusus Bergsten described in 2006
Works Cited
1.Taxonomic revision of the Holarctic diving beetle genus Acilius Leach (Coleoptera: Dytiscidae)
Bergsten, Johannes & Miller, Kelly B. 2006. Systematic Entomology, 31: 145-197.
2.A World Catalogue of the Family Dytiscidae, or the Diving Beetles (Coleoptera, Adephaga)
Nilsson and Hajek. 2019. Distributed by authors.
3.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.
Contributed by Eric R. Eaton on 21 November, 2005 - 1:21pm
Additional contributions by Robin McLeod, t.loh, v belov, Claude Tessier
Last updated 5 June, 2023 - 5:08pm

Disclaimer: Dedicated naturalists volunteer their time and resources here to provide this service. We strive to provide accurate information, but we are mostly just amateurs attempting to make sense of a diverse natural world. If you need expert professional advice, contact your local extension office.

Contributors own the copyright to and are solely responsible for contributed content.
Click the contributor's name for licensing and usage information.
Everything else copyright © 2003-2023 Iowa State University, unless otherwise noted.

Bugguide is hosted by:

Plant Pathology, Entomology and Microbiology at Iowa State University logo

Printer Friendly Version 		Terms of Use
Privacy Statement
Site Map
Contact