Hammerpede

The Hammerpede is a worm like creature seen in the movie Prometheus.

Its origin is unknow, as it is either a native of LV-223 or was brought there by the Space Jockeys.

When it finds a host body it aproaches it and attacks it, then goes down the throat of the host, pesumebly killing the host of suffication.

It could be one of the stages of the Proto-Xeno, seen at the end of Prometheus, but it's not confirmed.