Arthropod leg
A jointed appendage attached to an arthropod’s body. It usually enables locomotion, but may be modified for swimming, grasping, feeding, or sensing.
Arthropod: An invertebrate animal with a segmented body, jointed appendages, and a chitinous exoskeleton. Arthropod legs are the jointed appendages characteristic of this animal group.
Arthropod locomotion: Movement by arthropods using legs, wings, body undulation, or other locomotor structures. Legs are the main propulsive structures in many forms of arthropod locomotion.
Raptorial leg: A grasping appendage modified to seize and hold prey or other objects. Predatory arthropods transform leg segments into fast-closing grasping structures.
Arthropod antenna: A paired sensory appendage on the head of most arthropods, especially insects and crustaceans. Antennae are jointed appendages too, but specialize in sensing rather than supporting locomotion.
Arthropod appendage evolution: The evolutionary history of arthropod appendages and their diversification into limbs, mouthparts, antennae, and other structures. Leg diversity reflects evolutionary changes to an ancestral appendage pattern.
Arthropod exoskeleton: The external cuticle that supports and protects an arthropod’s body. The leg’s cuticle forms part of the exoskeleton and must accommodate movement at joints.
Insect gait: The timing and coordination pattern of an insect’s legs during walking or running. A gait coordinates leg movements so the body remains supported while advancing.
Swimming leg: An appendage adapted to propel an animal through water, often with flattened or fringed surfaces. Aquatic arthropods use modified legs as paddles or rowing structures.
Arthropod mouthpart: A modified arthropod appendage used to grasp, manipulate, or process food. Mouthparts share appendage ancestry with legs but are specialized for feeding.
Hox gene: A developmental regulatory gene that helps specify the identities of body regions and appendages. Hox genes help determine which appendage structures develop on particular body segments.