Kryptodrakon

Kryptodrakon is an extinct genus of pterodactyloid pterosaur from the Middle–Late Jurassic boundary of China, with an age of approximately 162.7 million years.[1] It is known from a single type species, Kryptodrakon progenitor. When it was named in 2014, Kryptodrakon was the basalmost and oldest pterodactyloid known.

Discovery and naming
In 2001, pterosaur bones were discovered in Xinjiang by Chris Sloan. The bones were first identified as those of a theropod; palaeontologist James Clark later recognized their pterosaurian nature.[3]

In 2014, Brian Andres, Clark and Xu Xing named and described the type species Kryptodrakon progenitor. The generic name means hidden dragon from Greek κρυπτός, kryptos (hidden), and δράκων, drakon (dragon). The name alludes to the film Crouching Tiger, Hidden Dragon. The specific name progenitor means ancestor or founder of a family in Latin, and refers to the animal's status as the most basal member of the Pterodactyloidea.[1]

The holotype, IVPP V18184, was uncovered in a layer of the Shishugou Formation dating from the Callovian–Oxfordian and having a minimum age of 161 million years. It consists of a partial skeleton lacking the skull. It contains fragments of both wings including the right fourth metacarpal, parts of the shoulder girdle and the second sacral vertebra. The bones were not articulated but were discovered in a small area of thirty square centimetres, at a considerable distance from other fossil remains, and thus likely represent a single individual. The bones were largely preserved three-dimensionally, without strong compression. The holotype probably was an adult individual.

Description
Kryptodrakon has an estimated wingspan of 1.47 metres (4.8 ft). Its fourth metacarpal is relatively slender and elongated, a strong indication that Kryptodrakon is a pterodactyloid. The fourth metacarpal has a minimum length of 72.2 millimetres, while the humerus has an estimated length of between 75 and 86 millimetres. These relative proportions are within the range of pterodactyloids. The radius shows an autapomorphy: it possesses an extra lump on the front outer lower side. The skeleton shows no signs of pneumatisation.