Transparent Mesh when rendering I am using camera tracking to make a short film and in render viewport you can see what I am trying to add (yes, those are butterflies). 
After rendering the scene the butterflies appeared transparent
 

As you can see in the first image my material is very basic on the butterfly. 

Here are my compositing nodes:  
They are the default camera tracking nodes... in blender internal.

I am using blender v2.77 on windows 10 with the cycles render engine.  

A similar, yet, unanswered question: Why won&#39;t objects appear in motion tracking?
You have a foreground and a background render layers. The background layer is setup to multiply shadows over the video layer (that's why the butteflies look like... shadows). The foreground is set up as alpha over and it should be the one that combines your scene color information over the background using an alpha channel. The issue is that your foreground layer is empty! You are rendering the contents of an empty layer and using the only layer that contains information as a mask!



Instead of an empty layer, use the layer that contains your scene.