Identification, Images, & Information
For Insects, Spiders & Their Kin
For the United States & Canada
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Photos of insects and people from the Spring 2021 gathering in Louisiana, April 28-May 2

National Moth Week 2020 photos of insects and people.

Photos of insects and people from the 2019 BugGuide Gathering in Louisiana, July 25-27

Discussion, insects and people from the 2018 gathering in Virginia, July 27-29

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Genus Efferia

TX Robber Fly - Efferia Robber fly - Efferia aestuans Robber Fly with Prey - Efferia - female unkn Robber Fly - Efferia Efferia aestuans ? - Efferia aestuans - male Robber Fly near Baker California - Efferia Asilidae  - Efferia Efferia jubata - male
Kingdom Animalia (Animals)
Phylum Arthropoda (Arthropods)
Subphylum Hexapoda (Hexapods)
Class Insecta (Insects)
Order Diptera (Flies)
No Taxon (Orthorrhapha)
Superfamily Asiloidea
Family Asilidae (Robber Flies)
Subfamily Asilinae
Genus Efferia
Synonyms and other taxonomic changes
Treated here broadly; species-groups used in the guide are sometimes recognized as separate genera Albibarbefferia, Aridefferia, Carinefferia, Nerax, Pogonioefferia, Tuberculefferia, e.g. in(1)
Explanation of Names
Efferia Coquillett 1893
from Latin efferus 'wild, savage'
~110 spp. in our area, 185 total(1)
more or less average in size, 15 to 25-30 mm(2)
Key to eastern spp.(3), key to others(4).
in our area, the vast majority are restricted to sw. US, with some widely western spp. and just two widespread spp.; Nerax predominantly southeastern(1)
Internet References