metastoma
From ZooTerms (Dictionary of Invertebrate Zoology)
metastoma (noun; plural -metastomata; Greek meta, after; stoma, mouth): 1. (Arthropoda: Crustacea) The lower lip posterior to the mandibles, usually cleft into paragnaths; hypostoma; hypostome; hypopharynx; labium.
2. (Arthropoda: Insecta) In Orthropera, the hypopharynx.
