I have a U. geyri, red phase (coloring looks like DoubleMom's Gizmo but orange). And when he gets warm and more hyper, his colors intensify, becoming more vibrant. When cooler, particularly in the morning, Gnuby can be very brown with muddy orange tones on top, his belly usually stays pretty bright regardless. Also, when warmer Gnuby's slight banding becomes more apparent and distinct. If you're just seeing pictures, the differences of lighting and flash use can greatly change the way these lil guys look!