Some Lizardmen designs I did for team-ChOW II on Conceptart.org. The next step was to do a full blown illustration of one of there (my favourite was the second one) but health problems forced me to bail out :[ I might try and finish it on my own at some point though.
There's a whole background story to their race and his character that I wrote down, but the leading factor in these designs was to enable the lizard to warm up or cool down easily as they can't regulate their own body temperature. Therefore their body isn't covered for the most part (their scaly skin is enough protection as is too). Note the foldable armor on the back of the first design, serves the same goal.