[Acantharia] Motor organelles consisting of contractile bundles of nonactin filaments (2-4 µm), twisted by pairs in elementary microstrands. Myonemes are located peripherally in the cell, grouped as umbrella ribs around each spicule. Myonemes can be flat, ribbon-shaped, cylindrical, triangular, etc.

schematic cross section
Pristacantha polyodon

Alternative form for Myonemes : Myofriscs.