Psion said:
Yugoloths are a family of daemons (daemons being a classification by mortal scholars), which includes non-yugoloth creatures like Guardian Daemons), just like not all devils are Baatezu and not all demons are Tanar'ri (or Qlippoth
).
Actually, this is incorrect, though it's easy to see how you'd come to this conclusion, given the ret-conning of the terms "demon" and "devil" for 3E.
In 2E, "demons" were tanar'ri and "devils" were baatezu. These terms only applied to those creatures. While there were other denizens of both the Abyss and Baator, they were not demons nor devils in any sense of the words. Bebiliths were just bebiliths, not bebilith demons. It was understood that calling tanar'ri demons or calling baatezu devils (though they virtually never mentioned the yugoloth/daemon thing) was something along the lines of a racial slur, and it tended to seriously piss them off.
In 3E, the terminology was ret-conned. Now, instead of the terms "demon" and "devil" being ignorant monikers for races that already had a name, they were now applied to the denizens of those planes as a whole. A "demon" was not the mortal name for a tanar'ri...rather, it was now the correct name for any creature that came from the Abyss, tanar'ri or not. The tanar'ri were now a specific sub-grouping of demon, and the same goes for baatezu and devils.
However, nothing has been done thus far with yugoloths and "daemons". So far, the term "daemons" hasn't been used in any WotC product for anything. Yugoloths, when they've appeared, have just been under the term "yugoloth" in the various monster books. While they're still their own family of creatures, they're not part of any larger, all-inclusive group.
As an aside, the guardian daemons are indeed part of the yugoloth group, since they were also renamed yugoloths in 2E, and so, having not been updated to 3E yet, remain so until we see otherwise. From the in-character standpoint, they are considered yugoloths because, although not part of the yugoloth hierarchy, they were specifically created by yugoloths to "soak up" summonings directed at them...between the guardian yugoloths, the canoloths, and the battleloths (from
Dragon # 306), the yugoloths are getting quite good at using biomancy to make new yugoloth creatures to fulfill their needs.
Of course, I voted for "yugoloth" since it sounds so much cooler than "daemon", which sounds too close to being a rehas of "demon".