Microphone access for SMS (Prime SE)

Hello all and a Merry Xmas to everyone.,

I have a Prime SE (using stock launcher) and was hoping someone might be able to tell me if the microphone is accessible from the small icon on the keyboard?
I would like to be able to compose and and respond to text messages by tapping the microphone icon direct from the keyboard and speaking a message (as I can do on my phone but my fingers are a little too stubby for stress-free keyboard typing on the watch).

Any help is gratefully appreciated. Thanks!