Pteranodon longiceps
"long-headed wing without teeth"

Above: Field guide style drawing of a large male Pteranodon longiceps. The pose is a partial crouch. It's likely that pterosaurs walked with more or less parasatagial front limbs, and this is borne out by known footprints. However, that wouldn't prevent the animal from moving a bit, as obviously the arms needed to splay during flight.

This is based on specimen YPM 2437, probably an old male, though Kellner 2010 considered it P. sp. tentatively, presumably due to the more upright crest. However, that's probably due simply to ontogenic change, as you can see in my modified Pteranodont profiles (below: left version reflects Bennett's taxonomy, the right Kellner's).

Note that Bennett considered "Geosternbergia" maysei an old P. longiceps, but given the weird crest incompletely preserved, and higher stratigraphic level, it's probably a distinct species. Bennett argued that all Pteranodon were a single anagenic lineage, so it really should be Pteranodon maysei, even if you place P. sternbergi in its own genus.

The Dawndraco specimen is an interesting case. On the one hand, it looks like it should fit in with the Geosternbergia complex, given the size and shape of its bill. Kellner 2010 noted that the crest base indicates an angle in between the largest-crested proper Pteranodon (which he referred to as P. sp) and the P./G. sternbergi holotype. The base is narrow like Pteranodon so it probably indicates a more traditional, narrow crest. It's tempting to think this can be slotted in as the most mature growth stage of P. longiceps, which would indicate a growth pattern for that species where an individual starts with a small stubby crest and short, stout bill. By adulthood, the bill and crest become hyper-elongated and the crest gradually angles upwards, becoming nearly vertical in the oldest individuals. However, given the apparent lack of any good associated bill material for adult male P. longiceps this would be difficult to test.

Image Details:
Media: Digital, Adobe Photoshop CS3 with WACOM Graphire 3
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