Black Butterfly

On weekend in early morning, I have seen one butterfly which just born from worm. We can see near the butterfly, there is one thing that look similar to worm. That one is the shell of the butterfly before it grows enough.

It is the first time that I have seen something nature which butterfly just leave its shell.

Black butterfly, what does it mean?
Excluding its wing, this butterfly body look like mosquito. Even thought, it is like that but it still look beautiful.

Started from first time I posted photo. There are two photos of butterfly with the same color black. But the shape and size are different.