Maxillipeds

Maxillipeds are specialized mouthparts found in crustaceans, especially in the subclass Malacostraca. They are the first three pairs of thoracic appendages that have been modified for feeding rather than locomotion. In decapods such as crabs, lobsters, and shrimp, the maxillipeds lie immediately behind the mandibles and in front of the walking legs, helping to handle and process food before it enters the mouth.

Each maxilliped is a multi-segmented limb with a proximal base and distal segments that end in a grasping or processing tip. They commonly bear sensory setae and may have enlarged margins or structures that aid in tearing, sorting, or directing food toward the mouth. The exact morphology can vary among species, reflecting adaptations to different feeding strategies.

Functionally, maxillipeds primarily seize, transport, and position food, aiding in prey capture, maceration, or the separation of edible material from debris. In some species, they also contribute to sediment brushing, filtering, or sorting tasks during feeding.

Taxonomic significance and variation: Maxillipeds are most prominent and readily identifiable in decapods, where the first three thoracic appendages are modified as feeding limbs. In many other crustacean groups, mouthparts are arranged differently, and the term maxilliped may not apply. Across taxa, the degree of modification and segmentation of maxillipeds can vary, making their morphology a useful character in crustacean classification.