Giant Robber Fly vs Petroleum Fly
Side-by-side species comparison
| Attribute | Giant Robber Fly | Petroleum Fly |
|---|---|---|
| Scientific Name | Promachus fitchii | Helaeomyia petrolei |
| Order | Diptera | Diptera |
| Family | Asilidae | Ephydridae |
| Size | 20-35 mm | 5 mm |
| Habitat | Meadows | Underground |
| Diet | Predators | Omnivores |
| Regions | North America | North America |
| Conservation | Least Concern | Least Concern |
Giant Robber Fly
A large, bristly predatory fly with powerful grasping legs and a sharp proboscis. It ambushes prey in mid-air with remarkable speed and precision, including insects larger than itself.
Did You Know?
Robber flies inject prey with saliva containing neurotoxins and digestive enzymes, liquefying the insides and then sucking them out.
Petroleum Fly
The only insect whose larvae develop in crude petroleum. Found in natural oil seeps in California, including the La Brea Tar Pits. Larvae eat insects trapped in the oil.
Did You Know?
This is the only animal on Earth that develops in crude oil — a substance toxic to virtually all other life. Its larvae swim through petroleum and breathe through snorkel-like tubes.