Dog Daycare Owner Claps Back at Molly Shannon's Claims He Called Her 'Ugly'

Molly Shannon slammed a photographer she says once called her "ugly" and says karma came for him because he runs a dog daycare now ... but he says she's full of (dog) s***!

Remember ... Molly got her star on the Hollywood Walk of Fame in June, and told a story about how a photog called her ugly while shooting her headshots. She said karma came back around, because now he picks up dog poop for a living.

Andrew Rosenthal, owner of LA Dogworks, tells TMZ … that story's about him, and things didn't go down the way Molly says, calling her version of events "a fantasy."

He tells us ... "I am obnoxious sometimes, but I don’t see myself saying 'you’re ugly.'" He also said he doesn't remember ever shooting her.

The former photographer added ... "If I did shoot her and said something negative, it possibly would have been in jest. We were friendly enough where something like that wouldn’t have meant to be hurtful."

He added, “However, she was a funny girl and clearly her gift was being a comedian.”

But the way Rosenthal tells it, Molly's story has a big hole ... he says no one shot headshots in color back in the '80s, which is what the comedian said he was taking for her.

He said she used to just come to his studio to hang out "forever," which he said "got to be annoying." He says it was so long ago that he thinks Molly should let it go and move on.

And Andrew says he pivoted to picking up poop because he opted out of photography when the industry went digital.