Looks like a normal 8 month old dragon to me, maybe just a dot on the small side... how long was it when you got it and how long is it now (head to tail).
They generally don't reach their full size until 2 years of age.
Its definitely a central bearded dragon, theres about 8 other species of bearded dragons and only one more out of those 8 others are in the US, that being the rankins/lawsons dragon and yours is definitely not that.
Can you please post a picture of the full setup?
Its diet is pretty bad so you need to fix that, at his age he should be getting calcium dusted on his insects 5x a week and multivitamins dusted on insects 2x a week.
Feedings should be 2x a day, each feeding consisting of 10-20 bugs.
Cut the pellets out of the diet, they cause digestive issues and don't offer any nutrition that a dragon needs.
Make sure your offering salad daily, that being collard greens, mustard greens, turnip greens, and then fruit added to that once or twice a week.
Heres a feeding guide to help out more, along with a simple
care sheet https://docs.google.com/document/d/18PfjxbgD95KLcfRCqGAVz-ViuMPuP4AvgGBSZzPKRgc/edit?usp=sharing
All life stages eat 10-20 bugs a feeding.
1-4 months 3x a day.
4-12 months 2x a day.
12-20 months once a day.
20+ months twice a week at the least, every other day at the most.
Staple feeders - Crickets, locusts, grasshoppers, silkworms, black soldier fly larvae, dubia roaches, turkish roaches, possibly earthworms.
Treat feeders - Waxworms, hornworms, superworms, mealworms, butterworms.
Wax worms - once a week, 4-5 max.
Hornworms - every other day to every two days, 4-6 max.
Mealworms - every other day to every two days, 5-10 max. Only for beardies above 6 months.
Superworms - once or twice a week, 3-4 max. Only for beardies above 12 months.
Butterworms - once or twice a week, 3-4 max.
Daily greens- Turnip/collard/mustard greens, endive, and kale if added to a mixture of the other staple greens mentioned.
Fruit once or twice a week - Banana, strawberries, blueberries, blackberries, red raspberries.
For more food items -
http://www.thebeardeddragon.org/bearded
http://www.beautifuldragons.com/Nutrition.html
You want two supplements at the very least, a calcium and a multivitamin.
Generally beardies below two years need calcium 5x a week and multivitamins 2x a week.
However beardies above two years or at two years of age need calcium only 2-4x a week with
multivitamins 1-2x a week.
This depends on how your adult beardie is with diet, health, just laid eggs, is laying eggs, etc.
Also what are you monitoring your temperatures with? Temp gun, stick on temp gauge, digital temp gauge with a probe?
What is the basking spot temp
what is the warm side temp
and what is the cool side temp?