A lost pup rescued from a Bronx subway tunnel has a new home with an MTA worker who found her shivering and covered in soot last week.

Delta, an adorable Shih Tzu-poodle mix, startled a group of track workers who found her tucked into a dark corner of an emergency exit near Fordham Road station last Wednesday, but melted the heart of Charles Gaston, who adopted her on the spot.

“She was completely black and all you could see was a little white spot on her head,” Gaston said, adding that he named her Delta after the D line where she was discovered. “She was just covered in track dust and grease, but wasn’t timid or afraid.”

The MTA worker said he and his co-workers took the filthy, matted animal back to their quarters and had to bathe her two or three times before she even started to resemble a dog.

“The second you put her in the water, it would all just turn black,” he said. “She was very matted and knotted up. It looked like she was down there for months.”

“Other than that, she’s a great dog and gets along with everyone,” Gaston added. “Once she was all cleaned up, she looked like a whole new dog.”

With none of the other workers willing to so much as touch her, Gaston said, he decided to take the dog to his Bronx home before having her groomed and vaccinated the next day.

“Nobody else wanted to take her,” he added. “My roommate already has another rescue dog, so I said maybe I’ll do the same thing.”

Gaston said he plans to keep little Delta but said he has been contacted by several people claiming she is their dog, and may give her up if he does find the rightful owner.

“I would hate to take her away from a child, but it would be difficult to give her up,” he said. “I’m already so attached to her.”