Rear derailluer broken bolt
This looks like the Syntace 142 mm X-12 axis bolt that also serves as the derailleur hanger. 

See https://www.pinkbike.com/news/syntace-142mm-12-norco-2011.html

Syntace catalogue (there are several lengths):
https://www.syntace.com/en_GB/products/liteville/accessories-spare-parts/630/x-12-screw-for-derailleur-hanger-28.5mm


Photo Syntace

In shops (be sure to buy the right length):
https://www.bike-components.de/en/Syntace/X-12-Derailleur-Hanger-Bolt-p24466/
https://www.bike-discount.de/en/buy/syntace-x-12-screw-for-derailleur-hanger-28.5mm-44555