Cuscuta is an example of:

Explanation

Cuscuta is a total stem parasite which is a good example of ectoparasitism. It is commonly found growing on hedge plants. It has lost chlorophyll and leaves in the course of evolution. It attaches and wraps itself around the stem of the host plant and produces haustoria that gets inserted into the vascular system of the host. The parasitic plant sucks all the nutrients from the host plant with the help of haustoria. Cuscuta is known to receive even the flower inducing hormone or florigen from the host.