I noticed that bug is aliased to arthropod while bugs is to insect. This doesn't seem right, one is just the plural of the other, shouldn't they just point to the same thing?
Relevant links I found:
https://e621.net/tag_aliases/3244
https://e621.net/tag_aliases/5798
https://e621.net/forum_topics/3480
https://e621.net/forum_topics/8556
https://e621.net/forum_topics/16386
https://e621.net/forum_topics/31464
Searching the forum for bug is difficult, maybe I missed something.