Common cutter beetle

Pikmin 4 the world to free
Tikes notes

I must say, these are quite the fighting machines. I was just luaghing on how slow they were, but Just after me saying that... it cut open one of my pikmin.. sign. I must be aware that until I have some way to remove their thick shells, It's going to be a rough battle for me. I also found out that their skins really some prickly. However, I found something that even more interesting. It's skin could have actually been harder than it own shell, but to how thin it is, it's still weaker.

Alices notes

Yuck! These creatures could really afford a makeover. They are indeed have roundish bodies with a knife like blade attached to it shell. Despite it's ugliness, they are actually quite friendly unless you anger or provoke it. However I always try to tell tike about this, but he won't listen. I wonder why?''

Spoilers 

Captain pikmins notes

Pink pikmin are the best against them because since with enough power, they can yank that shell right off to reveal that weak point. Without the pinks, bomb rocks shall do the trick.''