Who is julio on Jersey Shore?

There is no "Julio" on the Jersey Shore. The main cast members of the show are:

* Nicole "Snooki" Polizzi

* Jenni "JWoww" Farley

* Sammi "Sweetheart" Giancola

* Ronnie Ortiz-Magro

* Deena Cortese

* Paul "DJ Pauly D" DelVecchio

* Vinny Guadagnino

* Mike "The Situation" Sorrentino

There may be a character named Julio from other reality TV shows or another program that you're thinking of. Can you provide more context or information about what you're looking for?