Data from: Little bits of dragonfly history repeating exemplified by a new Pennsylvanian family

During its 320 million years evolution, dragon- and damselflies (Odonata)
wing morphology underwent intense modifications. The resulting diversity
prompted comparative analyses focusing on phylogeny. However, homoplasy
proved to plague wing-related characters. Concurrently, limited benefits
were obtained from considering fossil taxa, similarly impacted. Herein we
investigate two aspects particularly affected by convergence, namely the
acquisition of vein-like structuring elements derived from regular
cross-venation, termed conamina; and the evolution of butter knife wing
shape. Conamen implementation is found to be consistently linked with vein
curvature sharpening, itself generating potential breaking points.
Conamina therefore likely evolved to address wing integrity issues during
ever-more-demanding flight performance. Moreover, an existing conamen is
likely to trigger the acquisition of further, associated conamina. As for
butter knife shape, previously documented in the extinct Archizygoptera
and among damselflies, we report a new, 315-million-years-old occurrence
with the rare species Haidilaozhen cuiae gen. et sp. nov. (family
Haidilaozhenidae fam. nov.), from the Xiaheyan locality (China). The
repeated acquisition of butter-knife-shaped wing can be related to
slow-speed flight and, in turn, predator avoidance. In both cases of
iterated regularities, the unique ‘network-and-membrane’ wing design
proper to insects is found to compose a strong, constraining factor.