Alien (Attack the Block)

These here Alien appeared in 2011 movie called Attack the Block. These are an unnamed extraterrestrial species which crash landed on Earth through meteorite-esque cocoons. These aliens are quadrupedal, having long legs (all four legs are the same length), armed with bear-like claws, rows upon rows of sharp fangs, having no eyes, nostrils, or ears to speak of, and communicate through sonar, shrieks, screams, snarls, and growls. They are also a sexually dimorphic species, the females being dog-sized and almost completely hairless, while the males being gorilla-sized and having a very thick coat of hair, so black in color it doesn't reflect any light at all. The males are also seen to have bio-luminescent "glowing" fangs - which were initially mistaken for eyes. Their blood is blackish-blue in colour.

It is theorized in the film, that these aliens are invaders floating through space on solar winds, looking for a planet to "infest", and when the female finds a planet which is suitable, she excretes a musk-like fluid so the males are able to track her and then reproduce after landing on the planet, populating their new home. The fluid itself can be seen with ultraviolet light, although the males will relentlessly track anything with the fluid on it - including other living creatures.