Levels and spatial patterns of effective population sizes in the southern damselfly (Coenagrion mercuriale): On the need to carefully interpret single-point and temporal estimations to set conservation guidelines

The effective population size (Ne) is a key parameter in conservation and evolutionary biology, reflecting the strength of genetic drift and inbreeding. While demographic estimations of Ne are logistically and time-consuming, genetic methods have become more widely used due to increasing data availability. Nonetheless, accurately estimating Ne remains challenging, with few studies comparing Ne estimates across molecular markers types and estimators such as single-sample methods based on linkage disequilibrium or sibship analyses versus methods based on temporal variance in allele frequencies. This study aims at bridging this gap by analysing single-sample and temporally-spaced populations in the southern damselfly (Coenagrion mercuriale), a bioindicator Odonata species of conservation concern found in southwestern Europe’s freshwater stream networks. 77 local populations were sampled from a semi-urbanised area located in eastern France near Strasbourg city, yielding 2,842 individuals th..., , , # Levels and spatial patterns of effective population sizes in the southern damselfly (Coenagrion mercuriale): on the need to carefully interpret single-point and temporal estimations to set conservation guidelines

[https://doi.org/10.5061/dryad.83bk3jb34](https://doi.org/10.5061/dryad.83bk3jb34)

## Description of the data and file structure

-Microsatellite genotypes (samples locations and genotypes at 10 microsatellite loci)

-2092 SNPs genotypes (samples locations and genotypes at 2092 SNPs loci)

### Files and variables

#### File: Southern\_Damselfly\_Sample\_microsatellite\_genotype\_and\_locations.xlsx

**Description:** Southern_Damselfly_Sample_microsatellite_genotype_and_locations.xlsx – File containing for each sample: the name of the individual (Sample_Name), the name of the site where it was sampled (ID_Site), the sampling year (Year), population location (Longitude_EPSG4326 [East], Latitude_EPSG4326 [North]), individual multilocus genotypes at 10 microsatellite loci.

All...