Fossil insects

Despite the large number of extant species, fossil insects are found in a few deposits only, scattered across the globe and through time. Their fossilisation has been facilitated by the composition of their external skeleton, including a molecule resilient to alteration, namely chitin. One of the various forms of fossilisation, inclusion in amber, was popularised in a 1990’s science-fiction movie, Jurassic Park.

Presentation

Fieldwork and donations resulted in one of the world’s largest collections of inclusions in amber, as well as in Mesozoic and Cenozoic lacustrine laminites. It currently includes 30,000 fossil insects from lacustrine sediments and 20,000 preserved in amber, 10% of which are types and figured specimens, mainly from France. Most specimens are composed of complete individuals or of isolated wings.

History

The collection is based on a historical collection from the 19th century, comprising some of the first insects ever described, in ca. 1830. Over the last 20 years it increased more than tenfold.

The ancient collection mainly concerns the Upper Carboniferous, with the world’s largest series of insects from Commentry (Allier, France), including the famous giant ‘dragonfly’ Meganeura monyi. This set consists mainly of stem-groups of cockroaches & mantises (dictyopterans), grasshoppers, crickets & locusts (orthopterans), dragonflies & damselflies (odonates), as well as extinct groups. This collection contains several hundreds of specimens.

The Commentry insects were collected at the end of the 19th century in open pit coal mines. Scientific publications began with Charles Brongniart, from 1878 to 1893. These early  contributions were the beginning of a new research field. During the early 20th century, F. Meunier took over and established many new taxa. The material later underwent multiple revisions, notably by Franck M. Carpenter, from 1943 to 1964, and, during the 2000’s, by MNHN scientists. This led to a drastic reduction in the number of recognised species, and new proposals on the actual affinities of these insects. Finally, his investigation of the Commentry material led the Belgian entomologist Auguste Lameere to propose, in 1922, the insect wing venation groundplan commonly used nowadays.

Owing to its remarkable preservation and ‘exoticism’, the Commentry material is favoured by authors of popular science literature. In addition, uncertainties on the phylogenetic affinities of several of these very ancient species regularly bring scientists to revise this material, in the light of recent discoveries made in other deposits.

Recent activities

The collection is used to carry out research in insect systematics and phylogeny, biogeography and palaeoecology, dealing with all the main insect lineages. Several tens of papers including data from this collection are published annually. Moreover, the collection includes numerous fossils used as temporal calibration points for phylogenetic reconstructions, a trend currently prevalent in the field of evolutionary biology.

Recent collections are the result of excavations led by the MNHN staff, sometimes with the financial support of private partners. Voluntary excavations conducted from 1980 onwards also contributed greatly to the increase of the collection. Areas of focus are, among others, the late Permian in the vicinity of Lodève, and the early Cretaceous of Charentes and Provence.

Contacts

Olivier Béthoux, Lecturer and co-Loan Manager
obethoux [@] mnhn.fr
Tel. +33 1 40 79 30 61

André Nel, Professor
anel [@] mnhn.fr
Tel. +33 1 40 79 33 85

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