This project is for observations where the the organism being observed is living as a passenger of a vehicle! This can be anywhere from a plant growing out of a car or a spiderweb on a train. Organisms temporarily in a car (like a fly that flew in and back out of a car) aren't exactly what this project is for, this is more for organisms that call the vehicle their home.

I suppose the counterpart project to this is Road iNatting, where YOU are the passenger and the organism being observed doesn’t have to be. (If you’re both in the vehicle, does that mean that you can put it in both projects? I’d say yes!)

The vehicle can even be broken down or abandoned! Just if it is, please fill out the observation field “Is the vehicle in use?” and choose “No”.

"Epivehicular", as far as I can tell, was coined by @eralverson in their observation of a licorice fern in a car's mudflap.
Project icon from my observation here. less ↑