I have jupyter/anaconda/python3.5.
How can I know which conda environment is my jupyter notebook running on?
How can I launch jupyter from a new conda environment?
As mentioned in the comments, conda support for jupyter notebooks is needed to switch kernels. Seems like this support is now available through conda itself (rather than relying on pip). http://docs.continuum.io/anaconda/user-guide/tasks/use-jupyter-notebook-extensions/
conda install nb_conda
which brings three other handy extensions in addition to Notebook Conda Kernels.