solenidion
From ZooTerms (Dictionary of Invertebrate Zoology)
Arthropoda: Chelicerata) In Acari, a hollow, microcephalic, pili-, baculi- or claviform, seta-like formation of the tegument with thin walls, and large open roots, on the palp or legs; sense function unknown.
solenidion (noun; plural -ia; Greek diminutive solen, pipe): (