This is a monster from Kamen Rider Kabuto.

This is the Worms' first form, which looks like a chrysalis, but when threatened, the creatures can "molt" into a more powerful forms which enables them to move at blinding speed. Apparently, they do not need to naturally molt, as evidenced when Tendou (in Masked Form) shattered Bellcricetusworm's "cucoon" skin with the Avalanche Break. They seem to take pleasure in stealing their victims' identities. Furthermore, they can use multiple stolen forms to fit into the crowd. In addition, if their victim survives their attack and they cross paths with him/her again, they immediately go into a violent temperament in order to "finish the job." There seems to be some reasons for WORMs to kill the people whom they have stolen their identities from. In episode 14, a stronger type of Worm appears with white skin instead of the usual green. This "white Worm" was destroyed by Drake's Rider Shooting. When a Worm is destroyed, it explodes in the predominant color.

Green Version:
http://i19.photobucket.com/albums/b.....RMS/01Worm.jpg

White Version:
http://i19.photobucket.com/albums/b.....S/01Worm02.jpg

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