This is Klenn, a dragon I made that was modeled a good bit after a bat (if that wasn't already obvious...)

He is a small Wyvern with no breath weapon.
The quills along his ruff and base of his tail act as sort of outward telltale signs of his basic emotions:

Relaxed = at ease
Somewhat upright = curious, alert, or mild surprise
Up = interested, shock, or annoyance
Standing straight up = angry, very surprised, or embarrassed
Down = groggy, sad, or wary
Flat down against back = scared or upset

His species is as of yet unnamed and he is various shades of brown in color, with his eyes being dark orange with flecks and streaks of grey

He is small for a dragon and though young is as big as he's ever going to  get
2'7" tall
3'5" tip of snout to tip of tails
4'8" wingspan

His quills and tail tips are sensitive to air pressure and his late ears help him to pick up many frequencies of sounds from very far away, loud noises frighten him.

He has a forked tongue akin to a snake's that helps him do much the same in the way of "smelling".

He is a nocturnal species and largely consumes vegetation though is omnivorous and will eat meat as well.

His eyes, though not nearly as good as his ears, are very sensitive as well. He cannot stand harsh light.
His sense of smell is lacking, however, as is his sense of taste. Touch is intermediate.

To sleep his species usually finds a branch or something high and hand from it upside down by their tail, much like a bat.

His teeth are actually tiny compared to his body size and he isn't able to chew things like bones and such, thus his preferred foods are softer things.

Each individual is different but here is Klenn's personality:

He is cheerful, easily startled, curious about everything, a tad naïve, strives to be helpful, friendly, forgiving, and somewhat energetic.