wouldn't like to say for certain as there has been some terrible cross breeding with other large cichlids over the past few years, these have then been sold in shops as true sysnpillum.
however yours does look like a sysnspillum, though it is quite dark.
whether its male or female usually can be identified by the male developing a hump on its head.
as your fish still looks reasonably small (tell me if i'm wrong and its really 12"+!!!) it could be a female or an immature male.
sorry i can't be of more certainty.
i'm sure someone else will come along soon and make their comment.
could also be worth putting the post in the new world cichlids.