A while back we looked at the new Changchengopterus (the one that did not nest with the holotype). Here is a closer look at the hand.
Figure 1. PMOL Changchengopterus manus in situ and reconstructed. Click to animate to show flexor and extensor tendons. Note the presence of digit 5. The unguals invivo point ventrally, When crushed, like this, they often show their anterior (medial) faces. Shapes of the unguals are shown in gray. The pteroid articulates with the radiale.
Earlier we solved the problem
of flexor tendon insertion and flexion, here, here and here.
Figure 2. Traditionally digit 5 has been overlooked. Hopefully this GIF animation will help you see it. Look for an ungual, two other phalanges, a metacarpal and an carpal, as in Longisquama and Cosesaurus, but in this case all overlain by soft tissue (probably tendons) and riddled with cracks.
Earlier we looked at
the manual digit 5 problem in pterosaurs here, here and here. The reduction of manual digit 5 is documented here. Cosesaurus and Longisquama, two pterosaur outgroups, retain a distinct manual digit 5 of the same morphology.
Zhou C-F and Schoch RR 2011. New material of the non-pterodactyloid pterosaur Changchengopterus pani Lü, 2009 from the Late Jurassic Tiaojishan Formation of western Liaoning. N. Jb. Geol. Paläont. Abh. 260/3, 265–275 published online March 2011.