Tarantulas

Tarantulas are the largests spiders know today (the goliath bird-eater is the largest); they appear on tropical rain forests all over the world.

Biome/Spawn
There are Four species of tarantulas so far (each one have its own Mob Egg):

Mexican Red-Leg (Brachypelma emilia) spawn on Extreme Hills and are Uncommon.

Gooty Sapphire (Poecilotheria metallica) spawn on Roofed Forests and are quite Rare; very wanted for its metallic blue color.

Indian Ornamental (Poecilotheria regalis) spawn on Birch Forests and are Uncommon.

Goliath Bird-eater (Theraphosa blondi) spawn on Jungle Edges and are also Uncommon, but a bit harder to find then the mexican red-leg.

Behavior
Tarantulas have size to attack and kill some of the smaller spiders and beetles; they will be hostile to these mobs, and the Goliath bird-eater will also attack Chickens.

Tarantulas will bite the player if he punches it; they are quite fragile and not a real danger to the player. They make great collectables and can be put inside glasses with other mods. They will be tempt by spider eyes due their cannibalistic behavior. Tarantulas can Climb blocks.

Breeding
Yes; Spider Eye.