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Genus Efferia

robber fly - Efferia Efferia prairiensis with instar Orthopteran kill - Efferia prairiensis - female  Asilidae - Efferia aestuans - male Robber Fly Diptera Asilidae  - Efferia aestuans 74403 Efferia - Efferia Robber Fly - Efferia albibarbis Robber Fly with prey - Efferia - female Efferia tabescens - Efferia - 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