Rear Wheel Axle Nut "and greasing"

Hi
followed Mr Intruders instructions on how to remove the real wheel - a very good easy to follow instruction.

I noted whilst it is all apart and getting cleaned - that the nut - the same as Mr intruder had pictured does not appear to have any thing to stop it undoing - in the OEM diagrams there is a split pin pictured.

Question - when I put it all back together do I need to put locking solution on the nut? - has it lost a bit of grippy plastic? (technical term) and I need a new nut?

+ sorry two questions for the price of one - what should I grease - if at all - what should I grease it with (Christmas is coming and there is a goose in the freezer )

Cheers Guys

It is a lock nut Barney, it has a metal thingymebobv (technical term) inside to stop it coming loose, and just use general purpose grease on the spindle and 60% moly paste on the hub where the wheel is driven.

Thanks for the reassurance.  Now need to get 60% poly paste. I only hope if I pass away my wife doesn't sell my bike for what I said I spent on it!