If you have any difficulty fitting yours to the pictures there are some other sites that have pics of other Scarab grubs also, I just wasn't sure which were most likely in your area so went with the MO site.
One that we have around here that isn't on that Missouri list is the European chafer. On the MO site above you can ignore the black turfgrass ataenius because it's a little itty bitty thing compared to the others!
One thing with peering at the raster pattern is that the grubs usually take a very dim view of proceedings making it difficult to see. I saw a suggestion the other day that setting them in sand with their bottoms up can help. Another less pleasant way is to cut the grub in half so that it can't curl the raster away from you. Have fun
