What are the two primary body segments of an arachnid?

Arachnids are classified as having two primary body segments: the cephalothorax and the abdomen. The cephalothorax is a fused segment that combines elements of the head and thorax, containing the eyes, mouthparts, and legs. This unique structure distinguishes arachnids from many other arthropods, which typically have a clearly separated head and thorax. Following that, the abdomen houses the reproductive organs and digestive systems. This segmentation is crucial to understanding arachnid anatomy and differentiates them from insects, which have three body segments (head, thorax, and abdomen). Recognizing these two segments is essential for proper identification and study of arachnid behavior and physiology.