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Following the latest government announcement concerning the current Covid-19 pandemic the Society headquarters at Mansion House has now closed.

Where possible emails will be monitored, any urgent enquiries should be forwarded to info@royensoc.co.uk

Membership applications will be put on hold until further notice.

Our "identify that insect" service will continue, but our Director of Science cannot accept any physical samples to inspect during this time. identifythatinsect@royensoc.co.uk

Our Librarian will not have access to our collections from home, but will be happy to try and locate references available to download from the internet. val@royensoc.co.uk

All events and meetings have been cancelled until further notice https://www.royensoc.co.uk/events

We hope that everyone stays well and we hope that normal business can resume soon for everyone, thank you for your understanding during this difficult time that the world finds itself in.

Kirsty Whiteford - Registrar

Palaeoptera

The winged insects, or Pterygota, are undoubtedly a monophyletic group in that wings have developed only once in their evolutionary history; moreover the possession of wings has probably been the single most important factor in the success of insects as a whole. Within this group there are two distinct kinds of wing construction; in the Palaeoptera the wings can only be held upright or outstretched at rest, whereas in the Neoptera the wings can be flexed or folded flat over the body. The difference is simply due to a muscle attached to a small sclerite at the base of the wing. By enabling the twisting and folding of the wings this small muscle has probably enabled insects to evolve the complex wing-cases seen in several groups, as well as other adaptations. It seems clear that the presence of this flexor muscle, along with other related features, means that the Neoptera are a monophyletic group. The situation in the Palaeoptera is less certain, as some characters support the monophyly of the group, while others suggest that it is paraphyletic. In either case, the Palaeoptera are generally considered as the most primitive of the winged insects, comprising the Ephemeroptera and Odonata. The fact that both groups have aquatic juvenile stages is probably the result of convergence, as it is unlikely to be the primitive condition of the insects.

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