nympha
From ZooTerms (Dictionary of Invertebrate Zoology)
Arthropoda: Chelicerata) In Acari, sclerites beneath the epigynium.
nympha (noun; plural -phae; Greek nymphe, bride): 1. (
2. (Mollusca: Bivalvia) The immersed area behind the beak that strengthens the margin to which the ligament is attached, or reinforcement for the normal hinge structure; ligament fulcrum; sometimes nymph.