Download high resolution image here.

This is a closeup of the lateral view of the larva's head, best showing its medial crest in profile. The anterior view shows the crest is wedge-shaped, thinning to a knife-edge ventrally. I used a lime-green background for this shot to show clearly that you can see the through a triangular area at the bottom of the wedge. This is a thin transparent plate or blade supporting the crest (as opposed to an open area) based on the refractive distortion of the view of moving objects seen through it with a dissecting microscope.

This image is from a CombineZP processed stack of 177 images with a 0.9 micron step taken with a Nikon BD 60X 0.80NA microscope objective + adapter/extension tube + Nikon D300 camera.