Pterodactylus? kochi? B St 1878 VI 1 ((Zittel 1882, No. 13 of Wellnhofer 1970) Late Jurassic was originally considered a variation of Pterodactylus kochi. Here, derived from a sister to SMNK-PAL 6592, No. 13 was a phylogenetic predecessor to the much larger Eopteranodon and Eoazhdarcho.

Overall much smaller than and distinct from SMNK-PAL 6592, the skull of No. 13 was relatively smaller. The orbit was larger and the antorbital fenestra was smaller. The lacrimal was larger. The mandibular symphysis was longer and slightly more deeply keeled.

The cervicals were more gracile. The sacrals were shorter. The caudals were smaller.

The humerus was smaller. The distal wing elements were shorter. Fingers I-IV were more robust and shorter.

The pelvis was shorter with a larger space between the pubis and ischium. The hind limb was shorter and more robust. Metatarsal III was as long as mt II. Pedal unguals II-IV were aligned. Pedal 2.1 was shorter than p2.2.

The skull of No. 13 appears to have been closer to Muzquizopteryx and Eopteranodon, while the skull of SMNK-PAL 6592 appears to have been closer to Pteranodon occidentalis. On the other hand, the enlargement of the metacarpus and reduction of the antorbital fenestra in Eopteranodon points to a evolutionary path that first included a long metacarpus and long legs before the legs shortened in Muzquizopteryx and Pteranodon.

Size comparisons between germanodactylids are here. The family tree of the Ornithocephalia and Germanodactylia is here. The expanded family tree of the Pterosauria is here.

Hone and Benton (2006) reported, "The remarkable extinct flying reptiles, the pterosaurs, show increasing body size over 100 million years of the Late Jurassic and Cretaceous, and this seems to be a rare example of a driven trend to large size (Cope’s Rule)." They arrived at this "result" by drawing a straight line from early pterosaurs, like Anurognathus, to the Late Cretaceous pterosaur, Quetzalcoatlus over time and by deleting all purpoted juveniles. They did not realize that 1) there were four pterodactyloid-grade lineages; 2) the purported juveniles were actually adults; and 3) any sort of a roller-coaster effect of size increase/decrease/increase/decrease over time would be negated by drawing a straight line.