Artist’s name: crysothemis 
Artist websites: own website Chez Crysothemis, and on deviantart (and just 2 artworks on AO3, which I'll link below).
About the artist: Crysothemis is a USA-based fanartist and fanfic writer who used to be active in SGA fandom -  it's an older body of work, no longer being added to as far as I know. 
Why this artist is awesome: Crysothemis's art will be well known to SGA fans but I still love these drawings and watercolours and wanted to share them.  
Type of media used by this artist: mostly traditional - pencil drawings and watercolours, and a few digital works on Chez Crysothemis.
Fandoms in which the Artist has been active:  Stargate Atlantis, due South

Links to some of my favourite artworks by this Artist:

John Sheppard with, um, wings - a good example of Crys's skill with pencil drawings, also a cute pic of Sheppard looking wry about his wings.

In Depth Examination - a wonderful view of shenanigans in the waters under Atlantis. Click through a few times to see the whole pic for the depth and perspective, then for the close-up of the bottom of the ocean.

Renaissance men and Vitruvian John (NSFW - nudity) - an AU John and Rodney in a Renaissance setting. The first pic has strategic objects protecting John's modesty, but not the second one!