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

Genus Agabus

Predacious Diving Beetle lavae (Colymbetinae?) - Agabus Predaceous Diving Beetle - Agabus antennatus - female Agabus ambiguus Say - Agabus ambiguus Agabus semipunctatus (Kirby) - Agabus semipunctatus - male Agabus erytropterus (Say) - Agabus erytropterus - male Agabus ancillus (Fall) - Agabus ancillus - male 9019444 Dytiscid - Agabus Agabus semipunctatus - male
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 Agabinae
Genus Agabus
Explanation of Names
Agabus Leach, 1817
Agabus was an early follower and prophet of Christianity during the 1st century AD. (Wikipedia)
Numbers
Large and diverse holarctic genus; North America: 106 species (1)
Size
5-12.5 mm
Identification
Adults:
Eyes notched at antennal bases
Row of setae present on the ventral posterior apical angle (point where tibia and femur meet) of the hind femur
Hind tarsal claws subequal in length (compared to unequal claws in Ilybius)
Males can be separated from females by the broadly expanded front tarsi, which also bear numerous adhesive setae.
Species identification is often difficult given the large number of species in the genus and close similarities in appearance between species. However, there are a few exceptions that can be easily identified by colour alone. Examination of male specimens is often most reliable for species ID.
Larvae: similar in appearance to Ilybius larvae
2 whorls of hair on cerci (urogomphi) with or without secondary setae
lateral sides of the head without horizontal keel; row of lateral head spines do not meet the eye but run in an oblique angle below it (unlike Ilybius)
Range
Holarctic - Map (2)
Habitat
Various freshwater habitats- from vegetation-rich permanent ponds to lotic environments (streams and rivers); some also occur in temporary pools, others inhabit barren, mineral-rich aquatic environs in the arctic and alpine zones (1)
Food
Both adults and larvae are predaceous on smaller aquatic insects
Life Cycle
Various; most have been reported to overwinter as adults with breeding, egg laying and immature stages occuring in spring and summer but others may overwinter as larvae and/or eggs. (1)
See Also
Print References
For keys, full descriptions of biology and ecology, and range information for all known North American Agabus species see:
Larson DJ, Y. Alarie, and RE Roughley. 2000. Predaceous Diving Beetles (Coleoptera: Dysticidae) of the Nearctic Region, with emphasis on the fauna of Canada and Alaska. pp. 481-694.
Internet References
MCZ: Excellent images of pinned specimens representing 33 species
Discover Life in America: images and descriptions of several species