Empididae

dance flies, dagger flies, balloon flies

is a large of predatory comprising over 3,000 described distributed worldwide across all , with the greatest diversity in the Holarctic. are primarily predatory, capturing diverse including other , , , and other . The family exhibits notable behavioral diversity, including elaborate courtship rituals involving —males of some species present prey wrapped in balloons to females. occupy moist terrestrial or aquatic and appear to be predatory as well. Formerly, Hybotidae was included as a , but is now recognized as a separate family.

Trichoclinocera by (c) Zachary Dankowicz, some rights reserved (CC BY), uploaded by Zachary Dankowicz. Used under a CC-BY license.

Hilara lutea by (c) Katja Schulz, some rights reserved (CC BY), uploaded by Katja Schulz. Used under a CC-BY license.

Empis by (c) Ken-ichi Ueda, some rights reserved (CC BY), uploaded by Ken-ichi Ueda. Used under a CC-BY license.

Pronunciation

How to pronounce Empididae: //ɛmˈpɪdɪˌdeɪ//

These audio files are automatically generated. While they are not always 100% accurate, they are a good starting point.

Identification

Small to -sized (1.0–15.0 mm), slender to elongated in body form, never metallic. typically small and rounded with relatively large ; eyes of males often contiguous (). three-segmented with third bearing or style. Eyes frequently with incision at antennal level. variable—long and piercing in many , short in others; when elongate, projects forward or downward toward fore legs. Legs long and slender, often powerful; fore legs in some . clear or partially tinged, sometimes with spot or distinct pattern; radial R4+5 often forked; discal-medial (dm) almost always present; ends at or just beyond R4+5 or continues along wing margin. lobe on wing margin with axillary angle often diagnostic. Distinguished from and Hybotidae by unrotated, symmetrical terminalia; from Ragadidae and Atelestidae by with proepisternum forming precoxal bridge.

Images

Habitat

occupy diverse including forest understories, tree trunks, aquatic vegetation, stream , seepage areas, grasslands, agricultural fields, marshes, coastal zones, and beaches. Some frequent protected structures such as building interiors near matter. occur in moist soil, rotten wood, , and aquatic or semiaquatic environments.

Distribution

Worldwide in all ; majority of in Holarctic. Well-represented in North America, Europe, Asia, New Zealand, and elsewhere. Poorly documented in some regions such as Colombia (only six species reported).

Seasonality

particularly abundant in spring; activity patterns vary by and latitude.

Diet

are predatory, capturing diverse including other (including ), , , , , , , , , , , , and . Some adult groups (Iteaphila, Anthepiscopus, Anthalia, Allanthalia, Euthyneura) are exclusively , feeding on pollen and nectar. appear predatory on various arthropods, particularly other Diptera larvae.

Life Cycle

. hemicephalic with reduced capsule often retracted into ; eight-segmented with paired bearing hooks on 1–7 or 1–8; highly separated or absent; segment with one to four lobes. lack .

Behavior

are active , often perching on vegetation or substrates to scan for . Many form mating swarms where males aggregate and compete for females; in some species sex roles are reversed with females competing for male attention. Elaborate courtship rituals include presentation of -wrapped prey items ( balloons) by males to females; balloon composition varies from containing large prey to inedible dried items to empty silk or saliva constructions. Some species exhibit striking female ornaments including feathery leg , darkened , and inflatable abdominal sacs.

HybotidaeFormerly included as Hybotinae; now separate . Hybotids have smaller, more spherical relative to body and different .
Dolichopodidae typically metallic green, , or bronze; distinguished from by rotated and asymmetrical terminalia.
Asilidae are generally larger, more , with deep concave area between and bearded ; distinguished by these features plus different .