An Enviromarxist is a Marxist that uses the environment as a front for their attempt to destroy the socioeconomic status quo and implement a Marxist system. They do this to hide their true intentions and to gain support from affluent PC Liberals who want to appear as if they give a damn.
A primary example of Enviromarxism would be the opposition to the extension of the Keystone Pipeline from Alberta, CA to Texas, USA. President Obama has supported Enviromarxists in this endeavor. The Enviromarxist claims that the environmental damages that would be caused are too significant, when in fact any credible geologist says otherwise.
Another would be their opposition to fracking, which they claim causes earthquakes.