Here's a simple guide to help prevent confusion between bosses and Shinies.
Growth
All Pokemon, whether is boss, normal, or shiny, will have different sizes. Every time you level a Pokemon, they increase in size. The growth rate that these Pokemon have can be one out of seven different possibilities. The smallest is Pygmy, with everything after that being larger, and the largest is Enormous.
Normal Pokemon
This is a normal Charmander, everyone has seen and fought normal Pokemon; they are the most common kind of Pokemon. These Pokemon can drop certain items that can be used for many things.
Shiny Pokemon
As you can see, Shiny Pokemon also have white text for their name, the only difference is that they are discoloured. There is a 1/8192 chance for a normal Pokemon to spawn as a Shiny.
Blue boss
Blue bosses are coloured blue, and will have a blue name. They can also be called a boss 1 or bossmode 1. They are the most common of bosses and drop a variety of stuff.
Red boss
Red bosses are coloured red, and will have a red name. They are fairly uncommon as far as bosses go but when you see them you can get some great loot from them! They are boss 2 or bossmode 2.
Yellow boss
Yellow bosses are coloured yellow, and will have a yellow name. They are the rarest of bosses available and are sure to drop some good stuff when killed.
We do not recommend catching these bosses for they sometimes mess up data files if done a certain way. I am still looking into that. They will not stay the same colour or size upon catching them.