Here are a couple underwater creatures, a deep-sea lobster from far off the shores of Metru Nui, and a Mahri Nui crab with asymmetric claws:
How about some forest dwellers? This flexible tree lizard and poisonous tree frog are common creatures that Toa Lewa grew up around. The blue & green Fikou tree spider, on the other hand, is a rare spectacle.
In the mildest climate zones around the Matoran Universe you might have occasionally come across a parakeet-like winged rahi like so: