Asilidae
Common Name
Robber Flies
Overview
Asilidae, commonly known as robber flies, are a diverse family of predatory insects known for their aggressive hunting behavior. They are characterized by their strong flight, bristly bodies, and distinct predatory habits.
Taxonomy
Key Characteristics
- Size: Ranges from 3 mm to over 50 mm.
- Body Shape: Slender to robust with bristly hairs.
- Head: Large compound eyes, often with a "moustache" of bristles (mystax).
- Antennae: Short, typically with three segments.
- Mouthparts: Piercing-sucking type, adapted for predation.
- Wings: Membranous with well-defined veins.
Life Cycle
- Egg: Laid in soil or plant material.
- Larva: Soil-dwelling, often predatory or scavenging.
- Pupa: Pupates in the soil.
- Adult: Emerges from soil; lifespan varies by species.
Behavior and Ecology
- Feeding: Predatory; attacks a variety of insects including other flies, bees, and wasps.
- Hunting: Uses strong flight and raptorial legs to capture prey mid-air.
- Habitat: Found in diverse environments ranging from forests to grasslands.
- Diurnal: Active during the day, often seen perching in sunny areas.
Notable Species
- Promachus vertebratus: One of the larger species known for its powerful predation.
- Efferia aestuans: Widespread in North America, recognized for its distinct body markings.
Conservation
Most species of Asilidae are not currently threatened, although habitat destruction can affect local populations. Conservation efforts focus mainly on maintaining their natural habitats.
Significance to Humans
- Pollination: While not primary pollinators, they contribute to controlling pest populations.
- Scientific Study: Used in studies of predator-prey dynamics and insect physiology.