Steven gives it to you on the route east of fortee city.
You have to find Steven and he'll give you Devon Scope and you use that on the invisible object.
you have to find steven get a Devon scope and use it on the invisible keckleon in front of the gym
im sure you should use devon scope and if not i dont know and where is that route?!
Make your way to lilycove. Use the map and devon scope. It should be south then east.
Kecleon can be found in Routes 118, 119, 120, 121 & 123, as well as by the Devon Scope on 120 (going down to the water and on the bridge - Steven will guide you to the latter). You startle one in Fortree (on the way to the gym), but it leaves.
Devon Corp. is located in the north-west corner of Rustboro City.
mauvile city
You go past Fortree city and go through some more tall grass and there will be a bridge. Go down the bridge and Steven will give you the DEVON SCOPE.
in the cave where aaron are found
You deliver Devon's Goods to Captain Stern who is in Slateport City's museum.
head back to the Devon building to report mission sucsess
If given to the Devon researcher in the Devon corporation the claw fossil can be revived into Anorith.