Acheilous is the first and most pleasing of them (even if the dictionary suggests that achilous is a better way to spell it). It means "without a lip".
Adventious (the same as adventitious), aerious (airy), affectious and anemious are all rare, arsenious is chemical and arterious is archaic, but I could see myself working caesious into a conversation if I ever needed a word for bluish or greyish green. To neglect such a word would be tragedious.
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