A step up from the usual lift-the-flap animal board books, Spot the Animals by the AMNH has a rainbow theme featuring six accurately depicted animals with their proper names — e.g the red crab is a ghost crab, the green snake is the emerald tree boa, etc. — as well as some basic facts about them.
My daughter loved to point to and name all the colours and the animals, and she didn’t get tired of it despite reading it daily for over a month!