[Nerwen]

I know. "Shelob" sounds scary. "Kankra"... nothing much. Could be a disease.

In this case I think the translator may as well have kept "Shelob". The name doesn't mean anything in Standard English anyway.

By the way–

If anyone is curious about the words "bunyip" and "yowie" (from the celebrated Australian translation), they refer to legendary monsters.

A yowie is a large shaggy humanoid (like a yeti). A bunyip is a water monster that lurks in lakes, swamps and, of course, billabongs, preying on unwary swimmers. Nobody knows what they look like, since nobody has ever seen one and lived to tell the tale.

On the other hand, everyone in Australia knows someone whose friend's uncle saw a yowie one night.