The orange twining stems of the native parasite Cuscuta tasmanica growing on an unidentified succulent species at Lake Bolac, Victoria, Australia.
Commonly called "Dodder", this is a parasitic plant with orange thread-like stems that attach themselves to a host plant via haustoria. Once attached, the stem decays near the base and severs connection to its root. The Dodder then survives by taking nutrition from its host.
It is for this reason that the plant is orange; it has no chlorophyll and therefore doesn't produce its own energy from sunlight and carbon dioxide like most plants do.
Photographed with a Canon EF-S 60mm f/2.8 macro USM lens.