One of the Salarian entries brings up their naming traditions, which I hadn’t thought of since I last played through ME1. To quote:
Salarian names are quite complex. A full name includes—in order— the name of a salarian’s planet, duchy, barony, fiefdom, family, and finally, the given name.
And that got me thinking about Mordin. His name as it appears on dossiers and such, “Dr. Mordin Solus,” is, I imagine, a sort of Anglicized version, like how Japanese names are switched from surname/firstname to firstname/surname in other countries to follow local naming structure. Same way we rarely call a Hispanic person by their full name, which, if memory serves, uses both parents’ surnames (maiden name included).
So given that, I’m assuming Mordin is still the salarian doctor’s given name. Would Solus be his family name, then? I’m assuming he wouldn’t use any of the other possibilities, since that would give him a much broader identification, making it much easier to be confused with other, hypothetical Mordins.