NORTH-WESTERN JOURNAL OF ZOOLOGY;
Volume: 22 (No.1) - pp. 1 - 7 - Art no:e261101
They are here - Obama nungara - another invasive Geoplanidae species newly recorded in Bulgaria (Platyhelminthes: Tricladida)
Full-length research papers → Non-arthropod invertebrates
Authors
Vera ANTONOVA1, Simeon BORISSOV1, Teodora POPOVA2, Nikolay SIMOV3,*
1. Department of Animal Diversity and Resources, Institute of Biodiversity and Ecosystem Research, Bulgarian Academy of Sciences, 2 Gagarin Street, 1113 Sofia, Bulgaria.
2. Sofia University, Faculty of Biology, 8 Dragan Tsankov Blvd., 1164 Sofia, Bulgaria.
3. National Museum of Natural History, Bulgarian Academy of Sciences, 1 Tsar Osvoboditel Blvd, 1000 Sofia, Bulgaria.
* Corresponding author: N. Simov, E-mail: myrmedobia@gmail.com
DOI https://doi.org/10.61215/nwjz.2026.22.1.01
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Keywords
alien species, European Union, Black Sea Coast, mitochondrial DNA, land flatworms.
Abstract
The first record of the alien land flatworm Obama nungara (Platyhelminthes: Tricladida: Geoplanidae) in Bulgaria and on the Balkan Peninsula is presented. It was found in flower stocks and markets with exotic plants outside greenhouses near the cities of Plovdiv, Pazardzhik (Southern Bulgaria), and Burgas (Southern Black Sea) in 2024 and 2025. The locality in Burgas is the easternmost known in Europe. This is the second non-native terrestrial planarian species found in the country in the last two years. To confirm its identity with molecular data, mitochondrial COI sequences were obtained from eight specimens. Four unique genetic lineages were found in the Bulgarian material, comprising two clusters, each with two haplotypes. They correspond to the two clades ‘Argentina 1’ and ‘Argentina 2’, introduced to Europe. Both clades are known from France, Spain, and Italy. The species has likely reached Bulgaria through the intensive ornamental plant trade. The climatic conditions in Bulgaria seem suitable for successful overwintering outside greenhouses. Given the fact that O. nungara was officially added to the list of Invasive Alien Species of Union Concern in 2025 (EU 2025/1422), its presence in Bulgarian nurseries necessitates urgent phytosanitary oversight and measures. We recommend regular monitoring of invasive flatworm distribution, as they could contribute to a decline in soil biodiversity, primarily by reducing earthworm populations.
Article history
Received: 24 February 2026 / Accepted: 14 May 2026 / Published online: 15 June 2026 / Printed: 30 June 2026
Authors` ORCID IDs
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