Requires Unity 3.5.7 or higher.
Update 1.1: The plants have 1-2 small "idle" animation, using bones & skinning. Non-animated plant versions are also present.
Eight alien plants. Each has two variations in textures. Triangle number is 150-1000 (see the screenshots for poly distribution), textures are 512*512 and 1024*1024.
Textures are color (diffuse) only, no normal or specular maps.
You can also observe poly distribution on the wireframe screenshot.