Life history of Palaeozoic mayflies
Mayflies (Ephemeroptera) represent a very archaic group of insects. In a recently published paper, we presented results of our research on the Palaeozoic mayfly fossils from the Permian period.
Fig.: Larva and imago of the Paleozoic mayfly of the genus Misthodotes.
Specifically, the material consisted of several specimens of the genus Misthodotes, excavated in a famous Russian Tshekarda fossil site in the 60ies. Those specimens, measuring less than two centimeters and being more than 270 million years old, are excellently preserved, allowing us to observe minute details such as mouthparts, wing venation or tarsal claws.
We also described the thorax structure including details of the wing articulation for the first time in such an ancient lineage. According to our results, it was surprisingly very similar to the situation in their recent relatives. Contrary to the present day mayfly fauna, the Palaeozoic forms did not exhibit a well-known extremely short mayfly life expectancy. Adult mayflies today do not possess functional mouthparts and being unable to feed, they inevitably die very soon. In Misthodotes however, we documented a well-developed and probably functional mandibles, allowing them to enjoy life a bit longer.
We also studied nymphs of those Palaeozoic mayflies, which fossilized together with the adults. They exhibited a life style similar to modern forms, being aquatic (evidenced by well-preserved gills) and judging from the leg morphology, probably burrowing in the bottom substrate. Our work thus offer an insight on to how insects lived hundreds of millions of years ago.
Sroka P., Godunko R. J., Sinitshenkova N.D., Prokop J. (2021) Life history, systematics and flight ability of the Early Permian stem‑mayflies in the genus Misthodotes Sellards, 1909 (Insecta, Ephemerida, Permoplectoptera). BMC Ecology and Evolution 21: article number: 97. DOI: 10.1186/s12862-021-01820-x