42-year old Richard Kassebaum was taken into custody on Tuesday.
Police believed he matched the description of a man who assaulted the 23-year old woman in Forest Hills Park last week.
Prosecutors have left open the possibility of charging him again.
Kassebaum is still charged in a separate sex assault.
The suspect in the park attack allegedly approached the woman from behind, put the stun gun to the back of her neck, and sexually assaulted her. He also stole her cell phone.
The victim was able to fight off her attacker. She was rushed to the hospital for injuries to her neck.