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Calendar
BugGuide Gathering
Smoky Mountains
University of Tennessee Biological Field Station
August 8-10, 2008
Details...
 
Photos from the last gathering (Minnesota 2007)

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Family Asilidae - Robber Flies

Classification
Kingdom Animalia (Animals)
Phylum Arthropoda (Arthropods)
Class Insecta (Insects)
Order Diptera (Flies)
No Taxon ("Orthorrhapha" (Brachycera excluding Aschiza and Schizophora))
Superfamily Asiloidea
Family Asilidae (Robber Flies)
Pronunciation
ah-SILL-li-dee
Numbers
Insects of Cedar Creek lists 883 species for North America
About 530 general and 7,000 described species worldwide (Asilidae Home Page)
Size
5-30 mm (typically 9-15 mm)
Identification
Medium-sized to large predatory flies, often perch in exposed location and make short flies after prey. Typical family characteristics:
top of head hollowed out between eyes, with three ocelli in this depression (diagnostic character)
body from very hairy to nearly bare
typical body form elongated, with tapered abdomen, but other forms as well
some groups mimics of hymenoptera
face usually "bearded", with prominent mystax
mouthparts modified to inject saliva into prey--saliva contains potent neurotoxic and proteolytic enzymes
mouthparts similar in both sexes, unlike typical blood-sucking flies, such as Tabanidae
antennae with three segments, third segment elongate and often with terminal style
Habitat
A variety of habitats, but most diverse in dry, open habitats; larvae usually occur in soil or decaying wood.
Season
Typically summer
Food
Predatory on a variety of other insects.
Life Cycle
Adults lay eggs in the soil or in plants. A few, such as Mallophora and Megaphorus form an egg mass on a plant stem (see photo here). Larvae often predatory, consuming eggs and larvae of other insects in decaying matter. Typically overwinter as pupa, emerge in spring. Life cycle is 1-3 years.
Internet References
Univ. Florida--Featured Creatures, has Key to the Subfamilies of Florida Asilidae
Giff Beaton--southeastern robber flies
Herschel Raney--Arkansas and other robber flies
ENY 3005--Univ. Florida
Strickland's site--excellent scans