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


Genus Meloe - Oil Beetles

Is it a beetle? - Meloe americanus Which Oil Beetle? - Meloe campanicollis Meloe campanicollis - female No Clue - Meloe impressus Oil Beetle with Tachinidae egg? - Meloe impressus - female Oil Beetles - Meloe impressus? - Meloe impressus Female Oil Beetle - Meloe impressus - female what species? - Meloe americanus - female
Kingdom Animalia (Animals)
Phylum Arthropoda (Arthropods)
Subphylum Hexapoda (Hexapods)
Class Insecta (Insects)
Order Coleoptera (Beetles)
Suborder Polyphaga (Water, Rove, Scarab, Long-horned, Leaf and Snout Beetles)
Superfamily Tenebrionoidea (Fungus, Bark, Darkling and Blister Beetles)
Family Meloidae (Blister Beetles)
Subfamily Meloinae
Genus Meloe (Oil Beetles)
Synonyms and other taxonomic changes
Meloe Linnaeus 1758
Nearctic fauna revised in(1)
Explanation of Names
Origin obscure (2), though Blatchley (at one point) suggests the origin is Greek, "small animal" (3). The Oxford English Dictionary (link--login may be required) suggests it may come from early medical literature--the term melloes appearing in the writings of Paracelsus--that perhaps from the Greek for the scarab beetle Melolontha.
22 spp. in our area(4), >150 total, arranged into 16 subgenera(5)
12-30 mm(6)
Hind wings absent; elytra reduced and overlap at base.
Males smaller than females, with modified antennae:

Key to species, descriptions, and discussions in Pinto & Selander(1)
Primarily holarctic (mostly Palaearctic), with meager representation in more southern areas; throughout NA (to nw. Colombia; Hispaniola)(4)(5)
Ground or low foliage(6)
Larvae feed on eggs and other food in bees' nests(6)
Life Cycle
In at least some species of Meloe, triungulins aggregate and use chemical signals to attract male bees to which they attach themselves. This allows transport (and transfer) to a female bee who carries them back to her nest (Saul-Gershenz & Millar 2006).
First-instar larvae climb to the top of a plant as a group, clump together in the shape of a female solitary ground bee, exude a scent imitating the female bee pheromone. When a male bee comes and tries to mate with the clump of larvae, some of these clamp onto his hairs and eventually get to female bees when he mates for real. Impregnated female bees fly off and build nests in burrows; triungulins move to the new nests and feed on honey and pollen stocked by the bee for her own young. --Jim McClarin's comment
Beetles emit an oily substance from leg joints when disturbed (thus the common name)(6)
In males of some Meloe mid-antennal segments are modified, and the c-shaped ‘kinks’ involving antennomeres V–VII are used to grasp female antennae during pre-mating displays (Pinto & Mayor 1986)
Print References
Bland R.G. (1986) Antennal and mouthpart sensilla of the blister beetle, Meloe campanicollis (Coleoptera: Meloidae). Great Lakes Entomologist, 19(4): 209–215.
Pinto J., Mayor A. (1986) Size, mating success and courtship pattern in the Meloidae (Coleoptera). Annals of the Entomological Society of America 79: 597–604.
Saul-Gershenz L.S., Millar J.G. (2006) Phoretic nest parasites use sexual deception to obtain transport to their host's nest. PNAS 103: 14039-14044 (Abstract)
Works Cited
1.The bionomics of blister beetles of the genus Meloe and a classification of the New World species
Pinto J.D., Selander R.B. 1970. Ill. Biol. Monogr. 42:1-222.
2.The Century Dictionary: an encyclopedic lexicon of the English language
3.An illustrated descriptive catalogue of the Coleoptera or beetles (exclusive of the Rhynchophora) known to occur in Indiana.
Blatchley, W. S. 1910. Indianapolis,Nature Pub. Co.
4.American Beetles, Volume II: Polyphaga: Scarabaeoidea through Curculionoidea
Arnett, R.H., Jr., M. C. Thomas, P. E. Skelley and J. H. Frank. (eds.). 2002. CRC Press LLC, Boca Raton, FL.
5.The New World genera of Meloidae (Coleoptera): a key and synopsis
Pinto J.D., Bologna M.A. 1999. J. Nat. Hist. 33: 569-620.
6.Peterson Field Guides: Beetles
Richard E. White. 1983. Houghton Mifflin Company.