Morphology of the Mouthparts of Several Species of Phytophagous Mites

The morphology of the mouthparts of 5 families of phytophagous mites was studied. In tetranychid mites the stylets, or movable digits of the chelicerae, are concave mesally, forming a duct. A tiny dark line extending along the medial surface of one of the stylets may represent a groove which “hooks in” the opposing stylet when both are protracted. In the Tenuipalpidae, the tip of the rostrum is blunt, suggesting these mites feed differently from tetranychid mites in which the rostrum is cup-shaped apically. The eriophyoid rostrum consists of 5 stylets bordered closely by a pair of palps. Five segments compose the eriophyid palp, with the terminal segment pad-like. This segment perhaps adheres to the leaf surface, providing for forceful insertion of the stylets during feeding. In rhyncaphytoptid mites the terminal palpal segment is not pad-like but elongated, suggesting these mites feed in a different manner than eriophyid mites. In the Tarsonemidae, the mouth parts are located in the retractable capitulum. The palps are closely associated with the chelicerae.