Although some molluscs, such as landsnails, live on land, or in fresh water, like freshwater pearl mussels, the majority is in fact marine. We know of around 70,000 species, but there could be twice that number of species in existence.


Presentation
The marine, terrestrial and freshwater mollusc collection is essentially a scientific research collection, but also a historical and museological one. It comprises around 900,000 lots, representing around 5 million specimens from all over the world. Some of these specimens are dry preserved (dried animals, shells) and some are preserved in alcohol, including over 100,000 specimens fixed specifically for molecular analyses. The Typothèque contains the types of 13,000 nominal species. The collection is also of exceptional importance for endangered terrestrial and freshwater fauna, in particular from the Pacific Islands, where many species have become extinct.

History
The beginnings of the collection can be traced back to Michel Adanson (shells from Senegal, 1757) and Napoleon I’s Egypt Expedition. It then increased thanks to donations, bequests and institutional purchases, as well as the activities of in-house scientists and other travelling naturalists, in particular during the colonial exploration period. This diversity of sources persists to this day. However, expeditions have played a dominant role and continue to do so, particularly through the ongoing Tropical Deep-Sea Benthos and Our Planet Reviewed programmes.

Research
An estimated 50% of the world’s mollusc species are thought to be unknown. In this respect, the collection is an exceptional research infrastructure, fueling an international user network that combines professional systematists and high-level amateurs. A hundred or so visitors per year representing 1,500 person-days, and 80-90 loans representing 10,000 lots, are the source of a hundred or so scientific publications based on these collections. One out of two new marine mollusc species described in the world today is described based on this collection – representing an annual increase of 250 to 300 holotypes.
The oceanographic campaigns and major expeditions are the source of an average annual growth of 25,000 lots. The collection also contains samples collected by the IRD, CNRS and Ifremer teams as part of their own programmes. A large proportion of the collection is used specifically for DNA analyses: over 40,000 specimens have been sequenced, leading to the production of 50,000 sequences.
Part of the collection (types, published material and most of the collection fixed for DNA analyses) is directly consultable online. The WoRMS taxonomic authority list also features the Muséum national d’Histoire naturelle’s types. The molecular data relating to the collections are online in the BOLD (Barcode of Life Database) and GenBank databases. Station data and other information on research cruises and expeditions is found on http://expeditions.mnhn.fr/?lang=en_US.

Contacts
Philippe Bouchet, Head of Conservation of the General Collection
philippe.bouchet@mnhn.fr
Tel. +33(0)1 40 79 31 03

Philippe Maestrati, Curatorial Assistant of the General Collection
philippe.maestrati@mnhn.fr
Tel. +33(0)1 40 79 57 53

Virginie Héros, Head of Conservation of the Types Collection
virginie.heros@mnhn.fr
Tel. +33(0)1 40 79 31 04

Nicolas Puillandre, Head of Conservation of the "DNA" Collection
nicolas.puillandre@mnhn.fr
Tel. +33(0)1 40 79 31 73

Barbara Buge, Curatorial Assistant of the "DNA" Collection
barbara.buge@mnhn.fr
Tel. +33(0)1 40 79 38 19

Cystiscid microgastropod from the Madang lagoon © MNHN/PNI/IRD - Laurent Charles

Cystiscid microgastropod from the Madang lagoon © MNHN/PNI/IRD - Laurent Charles, par Laurent Charles

"New generation" collections
Beside the dry preserved shells, "new generation" collections include photos of live animals and tissues for sequencing. Above is a cystiscid microgastropod from the Madang lagoon, sampled during the Our Planet Reviewed expedition in Papua New Guinea.