For $su(p,q)$, I found Selim, Taufik Mohamed On maximal subalgebras in classical real Lie algebras. Selected translations. Selecta Math. Soviet. 6 (1987), no. 2, 163–176. See also this [MO problem][1]. [1]: https://mathoverflow.net/questions/102560/reference-request-for-the-list-of-maximal-subgroups-of-su3-1?rq=1%20%22MO%20problem%22.