http://anglers-diaries.blogspot.com/2008/12/double-rib-slim-profile-nymphs.html
The thread or quill body overlayed with a wrapped rib accentuates that segmented bi color appearance. I have found materials similar to Krystal Flash to be an excellent material for constructing sleek, wet looking body materials for chironomids and abdomens on nymphs and more life like than thread. Photo~ChromeOnChrome.com.
SwittersB & Exploring 