||Post-vent vasculature which forms an interconnecting network of venous tubes. The caudal vein plexus forms via a very active period of angiogenic sprouting, beginning at 25 hpf when venous endothelial cells of the posterior cardinal vein sprout and migrate ventrally, then fuse with neighboring tip cells. This process reiterates during a five-hour window, forming a primordial plexus by 30 hpf. By two days of development, the primitive caudal vein plexus has matured into a complex, well-perfused, venous vascular network. Starting at 4 dpf the caudal vein plexus starts to remodel and simplify.