Okay, I know we know who is dad is (the Black Manta) and that Mera knew this mother but really what do know of this origins - who is his mom. I have an idea who it could be. In the comics they said and I quote from the comicvine page/comics:

While pregnant with Jackson, his mother was attacked and apprehended by Xebelian outlaws in a lifeboat within the Bermuda Triangle. After taking the mother to Xebel, the Xebelian’s performed experiments on Jackson and his mother in an attempt to discover a biological escape mechanism from their underwater prison. His mother was killed during the experimentation, while Jackson lived. The experiments that were performed on Jackson gave him powers to manipulate water constructs, breathe underwater, and instantaneously grow webbed hands and feet.

Mera, fearing that the Xebelian’s or the Atlanteans would kill Jackson due to his suspected power to open the prison within the Bermuda Triangle, kidnapped him when she left Xebel. Mera brought the boy to a surface couple, who raised him as their own in New Mexico.

I think that Mera lied about his origins to project him from his mother who is her own tiwn sister, Hila. Hila, herself, has allied herself with the Black Manta several times and had once been exiled to the Bermunda Triangle. It could possibly be that she could never well be his mother especially after Brightest Day and Hila is current in pursuit of Aqualad and Aquaman for unknown reasons.

I know several fans who come to this conclusion too and believe to be true possibility. What do you guys think?