This is a hand-painted illustration of an Alien Xenomorph from the Aliens films, as designed by H.R. Giger.
The surface is gessoed illustration board, measuring approximately 14" x 17". It was penciled, then painted with an acrylic underpainting, then airbrushed. More acrylic was used to paint in the deeper shadows and details.
This piece is currently up for sale.
A process video will be online soon as well.