The Lauer Foundation for Paleontology provided
this tiny crushed Ctenochasma? elegans? Fig. 1) to the Field Museum, Chicago, USA. The foundation number is: #LF 2296. It enters the large pterosaur tree (LPT, 250 taxa; Fig. 2) distinct from all other tested pterosaurs.
Tiny, yes, but not a juvenile.
As we learned earlier, pterosaur hatchlings have adult proportions. Pterodaustro presents the phylogenetically closest example, in this case. Phylogenetic miniaturization is how we get tiny pterosaurs. And tiny pterosaurs are transitional taxa. That’s how we get derived pterosaurs. Note the tiny Ctenochasma? elegans specimens all nest together (Fig. 2). These tiny pterosaurs are adults that would have produced 8x smaller hatchlings, often about the size of house flies. and therefore unable to fly without risking desiccation due to a high surface-to-volume ratio. In other words, hatchlings of tiny pterosaurs could have flown, but needed to keep their wings folded. So they walked, picking up small prey in damp leaf litter. And that’s why so many pterosaur tracks are from pterodactyloid-grade pterosaurs, many of which continued to feet quadrupedally as they grew into phylogenetically larger genera.
Earlier we looked at the Fossilienatlas.de specimen
assigned to Ctenochasma elegans #204 (Fig. 4), which provides a similar morphology in reconstruction. No scale bars were provided with the Lauer Collection specimen, but the size can’t be too far off from this.