First record of the introduced ladybird beetle, Coccinella undecimpunctata Linnaeus (1758), on South Georgia (sub-Antarctic)
Data files
Sep 05, 2023 version files 10.83 MB
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Ladybird_measurements_ref.xlsx
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Ladybird_pictures_used_for_measurements.zip
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README.md
Abstract
Biological invasions represent a growing threat to islands and their biodiversity across the world. The isolated sub-Antarctic island of South Georgia in the South Atlantic Ocean is a highly protected area that relies on effective biosecurity including prevention, surveillance and eradication to limit the risk of biological invasions. Based on an opportunistic field discovery, we provide the first report of an introduced ladybird beetle on South Georgia. All specimens discovered belong to the Eurasian species Coccinella undecimpunctata Linnaeus (1758) (Coleoptera: Coccinellidae). Tens of individuals of both sexes were discovered at a single location, indicating that the species may already be established on South Georgia. Transport connectivity with this site suggests that the species most likely arrived recently from the Falkland Islands as a stowaway on a ship. We discuss the implications of our discovery for the continued development of South Atlantic biosecurity.
README: Data associated with "First record of the introduced ladybird beetle, Coccinella undecimpunctata Linnaeus (1758), on South Georgia (sub-Antarctic)":
Pictures of specimens under the stereomicroscope and associated metadata for size calibration associated with scientific article "First record of the introduced ladybird beetle, Coccinella undecimpunctata Linnaeus (1758), on South Georgia (sub-Antarctic)." Author: Pierre Tichit
Description of the Data and file structure
"Ladybird_pictures_used_for_measurements.zip" contains the original pictures of ladybird beetles taken under the stereomicroscope that we used to measure the pronotum and head width, as well as a picture of a 1 mm reticule used for calibration.
"Ladybird_measurements_ref.xlsx" contains raw and calibrated measurements of pronotum and head width.
- Column 1: numbered indexing of the 18 measured ladybird beetles;
- Column 2: Date of capture (dd/mm/yyyy);
- Column 3: Raw measurement of the pronotum width in pixels;
- Column 4: Raw measurement of the head width in pixels;
- Column 5 Raw measurement of the calibration 1 mm reticule in pixels;
- Column 6: Calibrated measurement of the pronotum width in mm (Column 4 / Column 6);
- Column 7: Calibrated measurement of the head width in mm (Column 5 / Column 6).