Gloomy scale (Melanaspis tenebricosa), an armored scale in the family Diaspididae
Eric Day, Insect ID Lab Manager @ Virginia Tech, kindly shared these wonderful gloomy scales with us one day during Insect Biology Lab. This picture shows two female scales (top-center) with their protective covers removed. The scale insects are the pink round things, and you can see their hardened pygidial (tail) region on their right. The scales in this stage really don’t have legs, eyes or antennae.
Gloomy scale pried from its feeding spot
In this image, the female scale is on its side (tail on the right), and you can see its very long thread-like mouthparts that are used like a straw to drink the juices of the tree.
Here are a couple identification resources for scales:
Virginia scale insects, by Eric Day (VT Entomology Insect ID Lab Manager):
http://pubs.ext.vt.edu/2808/2808-1012/2808-1012.html
List of all scale families, by USDA Agricultural Research Service:
http://www.sel.barc.usda.gov/scalekeys/scalefamilies/key/scale%20families/media/html/scalefamilies/FamilyListFset.html