Ben and I had a conversation about some of this in game and I will attempt to summarize the more coherent parts...
I do NOT believe that there are separate subraces between some aquatic and non-aquatic version. It is more likely that they have gills/underwater breathing capability left over from some prehistoric time when their desert homelands were actual oceans. The majority (perhaps all) of their current cultural history will be based on desert habitats.
re: Swimming ability. This is more based on environment and experience. All reptilians have the capability of swimming but only those living near water will know how to do it well. So it's a skill for which they have innate aptitude, but a skill none-the-less.
They probably don't have webbed fingers... though a broadness of hand and/or foot may still be well adapted for swimming. In the non-warrior class, it is likely that there tail could be used for swimming also.
Going along lines of the "warrior class" being a bred-in sub-race, the farther you get away from the ancient seats of culture, the more the reptilian people will resemble some combination of these traits. So things like tail length/shape, musculature, facial shape, horn placement/size can all be continuous variations between one specimen and another. Very few will exhibit all warrior or all non-warrior traits anymore.
Do they have claws? There hands are functional. If they have claws then they are more like well-kept talons. In all but the strongest of warriors, finger claws may be minimal. It is likely that a single or double claw appears somewhere on the forearm. Either some kind of retractable hook on the inside forearm (kind of like a velociraptor's hooked toe) or long exposed bones/horns that lay down on the outside of the arm (towards the elbow) that can be used for defensive blocking or in a back-hand hooking maneuver for holding prey close. Perhaps there is a crossed arm (elbow over elbow) opening move that can form deep slices in a prey's belly while also providing a good defensive posture before performing the move. (Imagine long teeth that protrude from directly outside the wrist, laying down towards the elbow. If you cross your arms nearly elbow-over-elbow then these 'teeth' are facing your prey. If you rapidly uncross your arms... well, I wouldn't want to be in the path of that.
)
Warriors probably aren't well adapted to swimming. They still have underwater breathing but their breed would not have needed swimming (heavy armor + swimming doesn't mix) and so are less suited to it the more warrior traits they have.
Reptilian skin may be marked or variegated. This may also indicate innate ability. I struggle with how to indicate things like a "shaman" of the tribe. Tattoos and piercings are one way... a natural coloring denoting a magic sensitivity are another.
Another possibility is that they may have some form of primitive feather that acts like hair. Like dinosaur feathers...
http://news.nationalgeographic.com/news/2011/09/pictures/110915-amber-dinosaur-feathers-color-science-birds-alberta/http://hardcorenerdity.com/files/2011/09/dei_head.jpgThis could be another distinction between warriors and non-warriors... either in relative amounts of hair, length, placement.
If it can be made to look cool and not stupid. I was actually kind of impressed with the dinosaur head pic there, though.
...and it would be unique.
Warriors will tend to be bigger and bulkier. More horns, etc..
The other end of the spectrum will be sleeker/stealthier. All still "scaly" like a lizard... and not slimy.
Mostly carnivores, though that may have been covered somewhere above.
...I think that's all that came out of the conversation. Maybe I forgot something... I definitely elaborated on a few of them.