Love the word "reveries"
A state of dreamy meditation, or did you know it can also mean composition of a vague and dreamy character.
You capture a simple moment of your dog snoozing and turn it into something more very well.
You manage to portray an almost rhythmic image of sleep where you can feel how relaxed your dog is and how you almost join him in his meditation, interestingly when you read again you almost read it at a slow, sleepy pace. It is a great art to have a poem flow so similar to its context. The pauses are in just the right places,
After descended on us, and tiny releases.
Like the final imagery in the last stanza, the double meaning of running either consciously or subconsciously.

However after saying all that, the first two lines both contain seven syllables each. They seem to flow one into the other, could you repeat this throught whilst keeping what I now decree as context pace?

I have to admit that when I read this, I teared up a little bit. It reminded me of my dog, and I miss him very much.

"He lays carelessly
on his side,
as I sit mere inches away
and watch how he sleeps
with his brown and white
spots lost in dreams
on his fur...."

^ This makes me think that he likes to sleep in your bed with you. I even bet that he had a tendency to take up most of the bed :D This is a beautiful image.

"His breaths come in
tiny releases,
his whiskers twitching
whenever he snores
too often,"

^ Beautiful picture right here in this stanza. I have always heard that when they are twitching, they are actually dreaming :) I always thought it was funny to watch them do that, because sometimes they reeeeeeally twitch, or at least mine did o.O I sometimes wondered if he was chasing a rabbit or something :D

Overall, beautiful poem even if it is to a dog :) I'm sure that if he was able to read that he would be jumping up and licking your face. Every pet deserves an ode sometime in their life for just being there :)

Excellent
5/5