What Kind Of Nose Knows? จมูกแด่น

I've just started reading The Story of Tongdaeng, Biography of a Pet Dog. The book is a welcome respite from Benjawan Becker's Advanced Reader.......and more my level of vocabulary. In describing the special characteristics of Tongdaeng, reference is made to the dog's จมูกแด่น. The book, which provides an English translation, says it's a nose with a white spot. My wife says it's more like a pushed up nose (but not as in a pug's pushed up nose). I can't find anything in the dictionary. Anyone have any ideas?