Identification of Roman Denarius

Hello, 

could you please help me to identify portrait on reverse of this Marcus Aurelius Denarius? 

I think it could be walking Mars but I can not connect the coin with exact RIC number. 

There is text “COSIII” on reverse. Diameter 18 mm, weight 2,84 g. 

Thanks a lot.

Second picture enlarged.

Salus with snake in her arms ? 🙂

for other emperor, same reverse : https://www.acsearch.info/search.html?id=200633

 Obverse looks something like this, 

with lettering starting below portrait - 

also similar ribbon behind 

 ANTONINVS AVG PIVS P P TR P III or similar 

 The other side was a miniature and not clickable 

https://en.numista.com/forum/images/69d911a454aed.png 

 Also reverse may show Salus standing right 

 Something like this, with that design above (not this one below) 

but the year before - COS III not COS IIII on reverse 

https://www.vcoins.com/en/stores/noble_roman_coins/325/product/antoninus_pius_denarius_salus_reverse/1995644/Default.aspx