I did email admin about this a few days ago, but no reaction as yet.
Admin is working up his energy to tackle all the spam that accompanies the legitimate email. Judging by the topics of the spam, Admin is lonely, desperate, underendowed, and deeply in debt. Not bad for someone who has only administrative existence!
My registration here currently has the aliases "cjhs", "cjhs aka Sylas" and "Sylas aka cjhs". I have never used the alias "cjhs aka Sylas"; that can also be deleted if you like.
Members may define as many aliases as they like, and they may move back and forth between them, too. This can all be done from the profile page, as you've already discovered. I haven't defined a way to delete an alias, and probably wouldn't permit it anyway if messages had already been sent under it, because it would orphan those messages.
If you hover your mouse cursor over your name, in most places it will list your aliases.
But "Sylas" is a separate account, so thanks for letting me know - that account is already gone.