Figure 2
(A,B) Light microscopic images of capture threads of juvenile spiders, showing the general structure of the cribellate thread. (C) Insight view of the cribellate thread, showing the axial fibers (af) at the rim of the zigzag aligned cribellate fibers (cf). rt: radial thread, sf: supporting fibers, uf: undulating fibers. SEM, carbon coated sample. (D–F) Close up of the puffs, showing the different types of fibers visible with different coating techniques in the SEM. (G) Simplified model of the internal structure of the capture thread of K. hibernalis. On the left side is depicted how both strands are interlocking to form one thread, and on the right side only one of two parallel strands were drawn for simplification. The cribellate fibers, accompanying the undulating fibers, are not depicted here. Original pictures are added to highlight the assembly of the different fibers in the puffs (upper right: light microscopy; lower right: TEM). (H) Splitting capture thread when pulling at the thread (here: down). Please note on the left side the different states of disruption: first the axial fibers break and then the supporting, before finally the complete thread ruptures (Movie 1).
