Small-sized Megasecopteromorpha (Insecta: Palaeoptera) occurred also in the Pennsylvanian

ABSTRACT

Pennsylvanian insects were popularised as past giants, but recent discoveries unravelled a yet poorly known component of small-sized forms. A new species of the extinct Megasecopteromorpha, a diverse but unabundant group iconic of late Palaeozoic times, is described from the early Pennsylvanian Xiaheyan locality based on a single individual preserving two wings. While Microhymen inconspicuus gen. et sp. nov. can be confidently assigned to the Bardohymenidae, its very small size, with a ca. 20 mm wingspan, makes it a distinctive member of this family. Its wing morphology is reminiscent of later, distantly related Permian Megasecopteromorpha belonging to the Protohymenidae and Asthenohymenidae. This new record allows highlighting traits likely to be acquired convergently as a consequence of size reduction.

KEYWORDS:

• Megasecoptera
• Xiaheyan
• late carboniferous
• new species
• convergence

Acknowledgments

We are grateful to two anonymous reviewers and Corentin Jouault for their useful comments and to the editorial board of the journal for handling peer reviewing and publication process; to Susan Butts, Jessica Utrup and Evan Chang (Yale Peabody Museum) for providing photographs of Megasecopteromorpha material from Elmo they are in charge of, and which helped us assessing wing venation homologies. We thank the President and Fellows of Harvard College for permission to use MCZ copyrighted material. This research was supported by grants from National Natural Science Foundation of China [No. 32020103006] and Support Project of High-level Teachers in Beijing Municipal Universities [No: BPHR20220114].

Disclosure statement

No potential conflict of interest was reported by the author(s).

Additional information

Funding

The work was supported by the National Natural Science Foundation of China [32020103006]; Beijing Municipal Universities [BPHR20220114].