The fossil shows remains of the soft parts, such as membranes and hair-like filaments. This was the first unequivocal proof that pterosaurs had a layer of hair-like filaments covering their bodies, later named pycnofibres. The pycnofibres served as insulation, an indication the group was warm-blooded, and provided a streamlined flight profile. The pycnofibres are present in two main types: longer at the extreme part of the wing membrane and shorter near the body. In the 1990s, David Unwin argued that both types were essentially not hairs but reinforcing fibres of the flight membranes.Elgin, R.A., Hone, D.W.E., and Frey, E. 2011. The extent of the pterosaur flight membrane. Acta Palaeontologica Polonica 56 (1): 99–111. Later he emphasized that "hair" in the form of pycnofibres was indeed present on the body, after the find of new specimens clearly showing this.
