Sinosauropteryx prima

Sinosauropteryx was a small theropod from the Early Cretaceous of Liaoning, China. It has the distinction of being the first non-avian dinosaur found with simple filamentous feathers preserved. Melanosomes preserved in the filaments show that they are not sub-dermal collagen fibers, and also indicate that Sinosauropteryx had a banded, reddish/brown tail, making it one of the first dinosaurs with a scientifically reconstructed color pattern.

Sinosauropteryx is usually considered to be a compsognathid, a proposed group of small, basal coelurosaurian theropods. That has recently been challenged, with Andrea Cau suggesting that instead Sinosauropteryx may be a juvenile of a larger, more basal tetanuran theropod, and that this might apply to other putative “compsognathids.” This is a new hypothesis that is not yet widely accepted, so we’ll have to see how it plays out in the scientific literature in years to come.