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S C HW E R P U N K T 50 »Bad Boy« of the beetles An international team of insect researchers has succeeded in recon- structing a long-extinct beetle with the help of a fossil. Despite being an impressive 250 million years old, Ponomarenkia belmonthensis has astounded researchers with its very »modern« features, which present scientists with a real taxonomic problem. PA L E O N T O L O G Y BY JULIANE DÖLITZSCH He is Australian, around half a cen- timetre long, fairly nondescript, 250 million years old—and he is currently causing astonishment among both ent- omologists and palaeontologists. The discovery of a beetle from the late Per- mian period, when even the dinosaurs had not yet appeared on the scene, is throwing a completely new light on the earliest developments in this group of insects. The reconstruction and interpretation of the characteristics of Ponomarenkia belmonthensis was achieved by Prof. Dr Rolf Beutel and Dr Evgeny V. Yan of Friedrich Schiller University Jena. They have published this discovery together with renowned beetle researcher Dr John Lawrence and Australian geologist Dr Robert Beattie in the »Journal of Sys- tematic Palaeontology«. It was Beattie who discovered the only two known fossilised specimens of the beetle in for- mer marshland in Belmont, Australia. »Beetles, which with nearly 400,000 de- scribed species today comprising almost one-third of all known organisms, still lived a rather shadowy and cryptic life in the Permian period,« explains Jena zoologist Beutel. »The fossils known to date have all belonged to an ancestral beetle lineage, with species preferring narrow spaces under bark of coniferous trees. They exhibit a whole series of primitive characteristics, such as wing cases—elytra—that had not yet become completely hardened or a body surface densely covered with small tubercles.« Earliest form of the »modern« beetle In contrast, the species that has now been discovered, assigned to the newly introduced family Ponomarenkiidae , can be identified as a »modern« beetle, in spite of its remarkable age. Modern char- acteristics are the antennae resembling a string of beads, antennal grooves, and the unusually narrow abdomen, taper- ing to a point. What is more, unlike previously known Permian beetles, the wing cases are completely hardened, the body’s surface is largely smooth, and the thoracic segments responsible for locomotion show modern features, notes insect palaeontologist Yan. In ad- Fossilised specimen of the »Bad Boy« Ponomarenkia belmonthensis (late Permian period, Age around 250 million years). 1 mm