The Eurasian lynx (Lynx lynx) is listed in CITES Appendix II and is protected under the Bern Convention and the EU Habitats Directive, yet it remains a frequent target of wildlife crime, highlighting the urgent need for reliable identification methods. This study focuses on determination and DNA quantification of the Lynx spp. using quantitative real-time PCR (qPCR). The Llynx Qplex quantification multiplex system effectively distinguishes Lynx spp. from other Feliformia species by targeting mitochondrial and nuclear markers. Additionally, we present the results of the developmental validation of the Llyn STRplex system for individual identification and databasing using six STR loci. This study followed ISFG recommendations for non-human DNA testing and developmental validation guidelines. Both systems demonstrate high sensitivity (5 pg genomic DNA for Llynx Qplex and 30 pg of mtDNA for Llyn STRplex) and high specificity to Lynx spp., confirmed by testing against 16 related Feliformia species. Robustness was evaluated, showing sensitivity to temperature variation, and both repeatability and reproducibility were successfully tested across replicates and conditions. Given that forensic casework often involves degraded and limited biological material, molecular tools must be both sensitive and specific to ensure accurate results. Developing precise and efficient tools is essential for supporting investigations of wildlife crime involving the Eurasian lynx, as well as efforts aimed at conserving the species.

Department of Ecology Faculty of Environmental Sciences Czech University of Life Sciences 165 00 Prague Czech Republic

Department of Forensic Medicine 2nd Faculty of Medicine Charles University 120 00 Prague Czech Republic

Department of Legal Forensic Medicine Bulovka University Hospital 180 00 Prague Czech Republic

Forensic DNA Service 170 00 Prague Czech Republic

Institute for Environmental Studies Charles University 128 01 Prague Czech Republic

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