Phantom Menace

I actually dont think they are similar, other than having an elongated body.

Because one is an insect with segments, looking more like a dragonfly with the body of a centipede, while the Star Wars one is more of a reptile mixed with a sea cucumber or eel and with the mouth of a crocodile.
Besides, they were in different planes, it had no wings, and the insect probably cant swim, they are just not the same kinda thing.

I have noticed that Miyazaki uses a lot of flora & fauna designs from the Devonian time period, mostly its fish, since it was the age of fish. The plants usually also look like prehistoric plants, maybe from the Carboniferous period.
But i dont think the Star Wars creatures are typical of known eras, other than early human history, with some exceptional animals like mutants or isolated monsters.
What im trying to say is that i think that Star Wars seems to go more modern fantasy with its designs, while Miyazaki seems to use more prehistoric designs.

On the other hand, i think Avatar is like a live action version of the Toxic Jungle.
The way they linked to animals also felt similar to the Ohm tentacles, and the floating jellyfish too. The Avatar idea itself felt more like Ghost in the Shell or something, but thats not relevant.

But to be honest, ive not really inspected the prequels much, ive only seen them twice so far, well except for RotS, but that one doesnt contain any special creatures as far as i remember.

I skip reading the bottom line, because it is usually some lame signature.