These Magnificent Tapeworms hail from Carbondale, Illinois. "Gnarley XXXMAS" was included on a 2010 album split with Egg Chef (it's the only holiday track). I think there might even have been physical CDs at some point. Both the album and the track can be had through Bandcamp on a "name your price" basis.
All credit and many thanks to Christmas A Go Go (and their tipster) for uncovering this quality recording and posting it yesterday.