The pattern, red edges to the fins, lips all scream Mozzy.
Niloticus have red eyes.
Males are most stunning when showing. Singly they develop a bit slower and don't color nearly as dramatically as a male showing for a beautiful lady does.
I loooove me mozzies. I've been keeping them for 5 years.
Young male
2-3" sexually active male.
4" non-sexually active male (he was allowed to become the dominant male of his group and thus matured much faster than any other male but was separated to allow other males to delevop faster)
5" spawning male
A good 16-18" single male. The father and grandfather and great-grandfather of all my mozzies.
18" niloticus for comparison
The shape of the mouth varies from specimen to specimen. I notice the males that develop the earliest always look the best with the widest mouths and smoother profile. I've had males color up in breeding dress and dig out their 3x their size spawning pits at barely an inch.
OP's looks to me like it could have been a late-blooming male. Considering how hybridized most Tilapia species are for aquaculture purposes I don't doubt it may not be pure mozzy, but that can be said of most hobby-bred species.
From what the fish looks like and from experience though, The fish looks like O. mossambicus.
