Welcome to the Marine Lab at Museum Victoria. Under the microscope today are three of the world's smallest starfish. They're about as big as your little fingernail; each arm is about five milimetres long.
Notice something wierd for a starfish? Well, the coolest thing, I reckon, about them is that they don't have five arms, they have six and they make new starfish by chopping themself in half and then growing new arms. This is called fissiparous reproduction and you can see it here. There are three long arms and three newly-developing ones. Here's another one with two big arms and four smaller ones, barely visible.It's just starting out a new life, this animal.
So, that's the world's smallest starfish. It's called a Paddle-spined Seastar and it was found here in Port Phillip Bay back in 2007.