ZooKeys authors Sam Heads, of the Illinois Natural History Survey, University of Illinois and Léa Leuzinger of the University of Fribourg, Switzerland, have discovered a 100 million-year-old fossil from a group of large, carnivorous, cricket-like insects that still exist today in southern Asia, northern Indochina and Africa.
“Schizodactylidae, or splay-footed crickets, are an unusual group of large, fearsome-looking predatory insects related to the true crickets, katydids and grasshoppers, in the order Orthoptera” said University of Illinois entomologist and lead author Sam Heads.
The find is from a fossil bed in Brazil. Although the specimen is different from modern splay-footed crickets, its general features are almost the same, revealing that the genus has been in evolutionary stasis for 100 million years.
The article, published in ZooKeys, vol. 77 (see also the wiki page of the species Schizodactylus groeningae) corrects the classification of another such fossil and shows that the genus has experienced almost no morphological change since the Early Cretaceous Period, a time when dinosaurs still lived, just before the breakup of the supercontinent Gondwana.
Evolutionary stasis is a common phenomenon at higher levels of the Linnaean system of biological classification (class, order and family). A body plan evolved in a kind of species, and found to work very well, is then adopted in slightly different forms by species after species. The truly extraordinary thing about the new fossil is that it is so much like its modern counterpart that it can be assigned to an existing genus – the lowest level of classification above a species – rather than to some higher taxonomic group, as is usually the case.
The news of this discovery provoked quite a reaction among scientific bloggers and newsgroups, being covered by the Economist; LiveScience; AstroBiology; NBC; Yahoo; Softpedia; Science Daily; Science Centric; PhysOrg: University of Fribourg; der Standard and others.
It was also covered on the Discovery Channel news show Daily Planet, and a clip is available to watch here (fast forward to 6 mins 50 secs).