Data on 1071 specimens of hoverflies collected or received by Jean Timon-David (1902-1968) and hosted at the Marseille Natural History Museum, France. The data set follows the GBIF format (https://www.gbif.org/darwin-core). In the CSV dataset format used here, fields are separated by tabs, all encoding is UTF-8, which allowed for all diacritic signs to be retained. Apostrophes (') were used wherever appropriate in locality names. Uncertain readings from the labels are indicated by a question mark in the verbatimEventDate or verbatimLocality fields. If the locality name was uncertain, no coordinates were given. This work is licensed under a Creative Commons Attribution (CC-BY) 4.0 Licence. All work derived from the present study should cite it appropriately, including the Museum where the material is held. For details see Nève G., Lair X., Lebard Th., Meunier J.-Y., Teste L.-J., Séguinel L. [submitted 12 Dec 2023] Hoverflies of the Timon-David collection (Diptera, Syrphidae). Biodiversity Data Journal. Fields used in the data set (Column label: Column description): occurrenceID: Individual identification code, same as CatalogNumber catalogNumber: MHNM individual identification: combination of Museum name, collection identification, box number and specimen number within each box basisOfRecord:The specific nature of the data record (i.e. PreservedSpecimen) eventDate: Event date in the format YYYY-MM-DD if the capture date is known to the date, or YYYY-MM if only the month and yaear are known, or YYY if only the year is known year: Year of capture if known month: Month of capture if known day: Day of capture if known verbatimEventDate: Date of capture, as mentioned on the label scientificName: Lowest taxonomic rank possible, usually the species name. If unknown the genus or family names are given. identificationQualifier: In case the identification could be given only to a species group 'cf.' is input. typeStatus: One specimen is a paratype, which is indicated here as such identificationRemarks: Any comment on the identification of the specimen kingdom: Kingdom (i.e. Animalia) phylum: Phylum (i.e. Arthropoda) class: Class (i.e. Insecta) order: Order (i.e. Diptera) family: Family name (i.e. Syrphidae) genus: Genus name specificEpithet: Species epithet of the scientificName sex: Male (M) or female (F) taxonRank: Taxonomic rank of the most specific name in the scientificName identifiedBy: Name of the entomologist who identified the specimen. The name is written within square brackets if it does not appear on the label, but can be inferred from other specimens with similar handwriting, locality and date. dateIdentified: Year of identification identificationVerificationStatus: Whether (coded 1) or not (coded 0) the identification was recently checked previousIdentifications: Species name originally given on the specimen labels minimumElevationInMeters: Lower limit of the range of altitudes indicated on the label or in the associated reference maximumElevationInMeters: Higher limit of the range of altitude indicated on the label or in the associated reference decimalLatitude: Geographic latitude (in decimal degrees) of the capture location decimalLongitude: Geographic longitude (in decimal degrees) of the capture location geodeticDatum: Coordinate system and set of reference points upon which the geographic coordinates are based (i.e. WGS 84) coordinateUncertaintyInMeters: Uncertainty in coordinates, in meters continent: Continent of capture country: Country of capture countryCode: Two letter country code of the specimen origin stateProvince: French departmental administrative division. In the case of non-French data, any relevant country administrative subdivision locality: Location of capture, usually the locality verbatimLocality: Any geographical indication on the label InstitutionCode: Museum where the specimen is held (i.e. MHNM) occurrenceRemarks: Any ecological data or comment on the label LocationRemarks: Any comment regarding the location recordedBy: Name of collector (i.e. legit information) associatedRereferences: Any reference citing the specimen organismQuantity: Number of individuals bearing the same label (usually 1) organismQuantityType: individuals georeferencedBy: Identity of the person who added the Latitude and longitude data, i.e. Nève, Gabriel georeferenceProtocol: How the georeference was computed, i.e. from label data (verbatimLocality) georeferenceSources: Georeference code was inferred from geoportail.fr, French ING maps or googleEarthPro georeferencedDate: Georeference work was performed in 2023 language: The data set is mainly written in French, apart from column headings, which are in English collectionCode: Identifier of collection (i.e. MNHN.15441) otherCatalogueNumbers: Any other catalog number the specimen may have