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


Species Mydas clavatus

Wasp? - Mydas clavatus Mydas Fly - Mydas clavatus Mydas Fly - Mydas clavatus Midas fly from Blounts Creek, NC  - Mydas clavatus Mydas Fly - Mydas clavatus Cicada or bee like insect in the grass? - Mydas clavatus Cicada or bee like insect in the grass? - Mydas clavatus Mydas clavatus
Kingdom Animalia (Animals)
Phylum Arthropoda (Arthropods)
Subphylum Hexapoda (Hexapods)
Class Insecta (Insects)
Order Diptera (Flies)
No Taxon (Orthorrhapha)
Superfamily Asiloidea
Family Mydidae (Mydas Flies)
Subfamily Mydinae
Genus Mydas
Species clavatus (Mydas clavatus)
Other Common Names
Mydas Fly
Synonyms and other taxonomic changes
Mydas clavatus (Drury, 1773)
Explanation of Names
Latin clavatus, clubbed; refers to clubbed antennae
25-30 mm length, wingspan to 50 mm or more
Large black fly with red/orange mark on top (dorsum) of 2nd abdominal segment. Body hairless, cylindrical. Eyes large. Antennae are distinctively clubbed in the Mydidae. This species flies rather boldly in the open. With the black-and-orange pattern, it resembles a wasp and fools the casual observer.
Throughout US and Canada--widespread. (As of 2012, BugGuide records were only from eastern and central regions.)
Deciduous woodlands and adjacent fields and shrubby borders.
Summer, June-August (North Carolina)
Adults sometimes found on flowers, presumably taking nectar (guide images). Some sources say adults take caterpillars, flies, bees, and true bugs. Others are skeptical of this.
Life Cycle
Eggs are laid singly in soil or rotting wood. (See video of oviposition--Flickr). Mydas larvae prey on beetle larvae, esp. those of June beetles. Larvae pupate close to soil (or wood?) surface. Illustration of larva and pupa:
Adults are active only in mid-summer. Mating system in this species unknown. Different Mydas species apparently have different mating systems, including resource-defense polygyny and "hilltopping". (See Preston-Mafham, p. 99, (1))
Batesian mimic of certain spider wasps (Pompilidae), e.g., Anoplius:
    - - >
Print References
Arnett, American Insects, p. 876 (2)
Borror and White, plate 13 (3)
Brimley, p. 335 (4)
Deyrup, p. 135--color photo (5)
Milne and Milne plate 459 (6)
Swan and Papp describe and illustrate the adult, larva, and pupa (fig. 1303) (7)
Internet References
Univ. of Arkansas Arthropod Museum--Mydas clavatus
Works Cited
1.The Encyclopedia of Land Invertebrate Behaviour
Rod Preston-Mafham, Ken Preston-Mafham. 1993. MIT Press.
2.American Insects: A Handbook of the Insects of America North of Mexico
Ross H. Arnett. 2000. CRC Press.
3.A Field Guide to Insects
Richard E. White, Donald J. Borror, Roger Tory Peterson. 1998. Houghton Mifflin Co.
4.Insects of North Carolina
C.S. Brimley. 1938. North Carolina Department of Agriculture.
5.Florida's Fabulous Insects
Mark Deyrup, Brian Kenney, Thomas C. Emmel. 2000. World Publications.
6.National Audubon Society Field Guide to Insects and Spiders
Lorus and Margery Milne. 1980. Knopf.
7.The Common Insects of North America
Lester A. Swan, Charles S. Papp. 1972. Harper & Row.