Petroleum Fly vs Hanging Thief Robber Fly
Side-by-side species comparison
| Attribute | Petroleum Fly | Hanging Thief Robber Fly |
|---|---|---|
| Scientific Name | Helaeomyia petrolei | Diogmites platypterus |
| Order | Diptera | Diptera |
| Family | Ephydridae | Asilidae |
| Size | 5 mm | 15-22 mm |
| Habitat | Underground | Farmland |
| Diet | Omnivores | Herbivores |
| Regions | North America | North America |
| Conservation | Least Concern | Least Concern |
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.
Hanging Thief Robber Fly
A slender, elongate robber fly that hangs from vegetation by its front legs while feeding. It has long dangling legs and a distinctive hunting posture unlike most other asilids.
Did You Know?
It earns its name by dangling from a single leg while consuming prey, freeing the other legs for handling food.