Sexing Nigerians is relatively easy. Check the bellies - if they're bright with black striping, they're male. If it's light colored with faint stripes it's likely female.
For care info, go to the uromastyx care sheets here on Kingsnake. There's several really good pages there including info on breeding. You can also look at www.deerfernfarms.com for good care info as well as photos of male and female Saharans (Nigerians).
Be aware that if they are freshly imported, this species is very sensitive and can be difficult to acclimate. Keep a close watch on them for the first several weeks and don't hesitate to get them to a vet if they seem off.
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Torey
Eugene, Oregon, USA
1.1 Uromastyx geyri (Joe and Arthur)
3.0 Uromastyx dispar maliensis (Tank, Turtle, and Spike)
1.0 Uromastyx ornata
1.2 Anolis carolinensis (Bowser, Leeloo, and Sprocket)
0.1 African dwarf frog (Sheila)
1.0 Betta splendens (Mr. Miagi)
1.1 Felis domesticus (Roscolux and Jenny)
