Help Identifying Antoninus Pius Coin 138-161 Ad

I had wondered about that Tanman2001. Thank you for the information :)

Another reason that the portrait is not Antoninus Pius who was emperor from 138-162 AD is that he was born in 86 AD. So he first was emperor at age 52. The image is that of a teenager. A real image of Antoninus Pius as emperor would show an older man. Also the legend says ..."AVG" which is an abbreviation for Augustus, or emperor. Further, the legend states TRPIIII, which means the coin was supposedly minted in the fourth year that the emperor was Tribune of the People. In other words, he was four years younger when he became emperor. At least four years younger. That means that that the emperor pictured would have been a child.
In order, the youngest emperors of Rome are as follows:
Valentinian age 4
Valentinian III age 6
Gratian age 8
Honorius age 10
Gordian III age 13
Elegabalus age 14
Severus Alexander age 14

Coins labeled Antoninus may be from Antoninus Pius, Caracalla or Elegabalas. There are many articles to sort out which is which.

The names of Antoninus and Marcus Aurelius were adopted by very many later emperors .
Around 15 I believe !

BTW
The list of juvenile emperors is missing both Caracalla ie Marcus Aurelius Antoninus (age 10) AD 198 and Diadumenian ie Marcus Antoninus (age 10) circa AD 218