Germanodactylus? cristatus? SoS 4593 (formerly PTHE No. 29 III 1950, No. 9 of Wellnhofer (1970)) was considered a juvenile Pterodactylus micronyx and a juvenile Germanodactylus cristatus. Here No. 9 was derived from as sister to another tiny pterosaur, Ornithocephalus, and it phylogenetically preceded yet another tiny pterosaur, No. 31.

Distinct from Ornithocephalus, the skull of No. 9 was longer and sharper. The ascending process of the maxilla was greatly reduced. As in Scaphognathus, the lacrimal process of the jugal leaned anteriorly and the pre-narial portion of the skull was longer. The jugal itself was extremely thin below the orbit, following a trend. The teeth were barely larger.

The caudals were more gracile, as in Scaphognathus.

The humerus was relatively shorter with a larger deltopectoral crest. Fingers I-III were larger.

The pubis was short and ventrally directed, as in Scaphognathus. The ischium had a dorsal process. Metatarsal I was as long as mtII. The pedal unguals were not so deep and II-IV were not aligned.

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.

Several correct and incorrect assignments to Pterodactylus. Click to enlarge. Many of these taxa (specimens) were assigned to the genus Pterodactylus by Wellnhofer (1970) and other authorities before the advent of computer assisted phylogenetic analysis and before most of them were graphically reconstructed and scaled to make comparisons easier. Furthermore, these assignments were made under the false assumption that pterosaurs, like mammals and archosaurus (including crocs and birds) changed as they matured, developing a relatively longer snout and smaller eye. Embryo pterosaurs demonstrate that relatively little changed during maturity, especially in the proportions of the skull.

Bennett SC 2006. Juvenile specimens of the pterosaur Germanodactylus cristatus, with a review of the genus. Journal of Vertebrate Paleontology 26:872–878.

Hone and Benton 2006. Cope’s Rule in the Pterosauria, and differing perceptions of Cope’s Rule at different taxonomic levels. Journal of Evolutionary Biology 20(3): 1164–1170. doi: 10.1111/j.1420-9101.2006.01284.x

Wellnhofer P 1970. Die Pterodactyloidea (Pterosauria) der Oberjura-Plattenkalke Süddeutschlands. Abhandlungen der Bayerischen Akademie der Wissenschaften, N.F., Munich 141: 1-133.