Pseudacris regilla (Pacific tree frog) seen in Ridgefield National Wildlife Refuge, WA, USA. The frog is really tiny. This photo is 1:1 macro, horizontal field of view is just 17.3mm:
And here is a bit farther away:
If you like the images, prints and apparel available via Redbubble: https://www.redbubble.com/people/sdymchenko/works/42304458-tiny-pacific-tree-frog-pseudacris-regilla-sitting-in-a-flower
You can license the photos for commercial and personal use via Alamy: https://www.alamy.com/tiny-pacific-tree-frog-pseudacris-regilla-sitting-in-a-flower-image259836856.html