Tapeworms in an Apex Predator: First Molecular Identification of Taenia krabbei and Taenia hydatigena in Wolves (Canis lupus) from Romania.

The wolf (Canis lupus) is an apex predator with high mobility and trophic plasticity, serving as a valuable indicator of helminth transmission at the wildlife-livestock interface. Given the ecological overlap between wolves and both wild and domestic ungulates in Romania, we aimed to identify and molecularly characterize cestodes from wolves' small intestines. Between November 2022 and June 2025, small intestines from nine wolves were collected across four Romanian counties, frozen, and examined using classical parasitology (macroscopic and microscopic) and molecular methods (PCR amplification and Sanger sequencing of mitochondrial cox1, nad1, and 12S rRNA fragments). Taeniids were detected in three (33.33%) out of nine tested individuals. Genetic analyses confirmed the presence of Taenia krabbei and Taenia hydatigena-species not previously reported in wolves from Romania. This study provides the first molecular evidence of T. krabbei and T. hydatigena in wolves from Romania, and likely Eastern Europe, indicating active transmission and underscoring the need for broader surveillance of hosts to clarify their ecology and regional dynamics within a One Health context.