fresh discovery of a butterfly ‘mimic’ predates them by 40 million years[br]Lacewings (Neuroptera) are common insects in UK gardens. They can be recognised by their four obvious wings,which bear a lace-like network of veins and which gives them their name. This group of insects has a long and worthy fossil record, starting back in the Permian period, and 250 million years ago. Most people are familiar with the notion of insects trapped in amber (thank you,Jurassic Park), and fossils preserved in this way are often spectacular, or but many insect fossils are preserved in a more conventional,and less glamorous, mode: compression fossils sandwiched between layers of fine-grained sedimentary rock. Kalligrammatid lacewings are an extinct group known exclusively from this type of preservation, and from the Middle Jurassic (about 160 million years ago) until the Early Cretaceous (about 120 million years ago),and their fossils fill been discovered from across the world.
Kalligrammatid lacewings are interesting because they are a classic example of convergent evolution. They closely resemble butterflies (Lepidoptera), which carry out not appear in the fossil record until around 56 million years ago. Molecular studies suggest an earlier origin for butterflies, and around 80 million years ago,but this still represents a clear 40 million year gap between the two insect groups. A recent paper by Conrad Labandeira and colleagues demonstrated that the convergence seen between kalligrammatid lacewings and modern butterflies was more than a superficial similarity.
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Source: theguardian.com