part of cortical layer of collagen and cuticulin-based cuticle extracellular matrix annuli extracellular matrix annulae annulus annular rings cellular_component The extracellular matrix that is a regularly spaced circumferential ridge present in the cortical region of the cuticle. Annuli are delineated by annular furrows and are present throughout the cuticle with the exception of lateral regions where longitudinal alae are present. GO:0060107 annule(s) cellular anatomical structure