My favorite animals have always been snakes. They're just so fascinating. It's pretty incredible to think that they more or less became apex predators in spite of not having any legs. There's also such a wide variety of snakes with very distinct features that makes them easy to identify. You have pythons, boas, mambas, kraits, vipers, seas snakes, colubrids, and of course, my personal favorites, cobras. They're all beautiful and incredible creatures.
Another favorite animal of mine is spiders (I tend to be drawn to animals that could easily kill me). Another facinating group of creatures, spiders are possibly the most misunderstood animal in the world. They're the second most feared animal in the world statistically with only snakes in from of them, but only about 20-30 species of spider has venom strong enough to kill a healthy adult. They eat other bugs like mosquitos and flies which carry diseases that are far more likely to kill us. Spiders play an extremely important part in human survival yet most people's reaction to seeing one is to either scream or kill it. It's a shame and something that I hope changes in the future.