acanthostyle
From ZooTerms (Dictionary of Invertebrate Zoology)
Bryozoa: Stenolaemata) A type of stylet with a smooth rod core of nonlaminated calcite, with sheath laminae usually strongly deflected toward the zoarial surface as spines; usually larger than paurostyle.
acanthostyle (noun; Greek akantha, thorn, spine; stylos, pillar): 1. (
2. (Porifera) A monactinal spicule covered with thorny processes.