Horseshoe crab

The chitinous armor of the horseshoe crabs is bisected, similar to that of scorpions.

An excerpt from the article 22 facts about Horseshoe crab
It consists of an anterior part or prosoma and a posterior part or opisthosoma. Prosoma of horseshoe crabs consists of 6-7 segments, while opisthosoma consists of 10 segments. The posterior-most division of the body of animal is called telson which is a long spike.