whered the last alien come from

I forget his name, but a security officer did get face wrapped for like 5 sec.  An baby xeno was placed in him, but because it was such a short amount of time, the xeno didn't get past his throat and came out of his mouth in the movie (at least that is how I remember it).  The security officer got wrapped on Paradise, made it to the Covenant ship, then the xeno came out of him.

There was also Oram who got facewrapped. Two others got spores.

evbenji, there was only two Protomorphs (the black, xeno-type things.) One was birthed form the captian and began hunting people in the temple and was the same one that Daniels killed with the crane. 

The second protomorph (the one on the Covenant) came out of Sargeant (spelling??) Lope. He was the one who almost got facehugged David's workshop. He also escaped the temple with Daniels. It was that guy. It seems a little silly that the embryo was placed inside of him without the full facehug and gestation of that, but that's how it happened. And, I Moon Girl, I believe that it did indeed burst from his chest (his body on the ground of the medbay seemed to have alarge hole in the chest)

Yep. A big hole. 

tdby2 well unlike you, i havent watched the cam job 18 times with a note pad, cup of tea and cookies, i saw it last night once at the cinemas only

yes thanks I Moon Girl, that explains it. 

didnt like that david didnt have a stab hole under his chin at the end, and the whole theory ive read that david uploaded his binary into walter is a bit too far fetched for the average non techie viewer 

noting also that merging binary i think is stupid too. I cant merge my windows 7 with a windows 10 ghost image, there can only be one. hiding what ever david did to walter might have added to the mystery but its left a massive hole to the story

nonetheless i was quite surprised there were lots of new concepts and when the civilization of the planets city and people was introduced that was incredible. the trailer showed nothing but replicated concepts from previous movies so was awesome to get some new intrigue in the saga during the movie

again david is therefore the creator/father of the Protomorphs?

also is this planet the same one that ripleys crew visits?