How to list only the last line of each directory?

I learned thanks to you, how to display only the last line of a listing,e.g.

ls -ltr | sed '$!d'

Now I thought, how to combine it with the find command, in order to repeat this onto each directory exitent, but I got only to a false solution:

find / -type d | xargs ls -ltr | sed '$!d'

If i read it right, this would not display the last line of each directory, but only the last line of all listings of all directories.

How to do it right ?