Sometimes they come back – Platypsyllus castoris Ritsema, 1869 (Leiodidae, Coleoptera) new genus and species for the fauna of the Balkan Peninsula

Rostislav Bekchiev; Nedko Nedyalkov; Rumyana Kostova; Nikolay Simov; Mario Langourov; Ilya Acosta-Pankov

Rostislav Bekchiev https://orcid.org/0000-0001-6143-0184; Nedko Nedyalkov https://orcid.org/0000-0003-4586-3224; Rumyana Kostova https://orcid.org/0000-0002-8119-3275; Nikolay Simov https://orcid.org/0000-0003-1626-2964; Mario Langourov https://orcid.org/0000-0001-6756-3420; Ilya Acosta-Pankov https://orcid.org/0000-0001-7275-0482

Volume 48 (Issue 4): 93–95 · 1 April 2026

Abstract: The parasite beetle on Eurasian beaver Platypsyllus castoris is reported for the first time from Bulgaria.

Keywords: beetles, Castor fiber, commensalism, Europe, Platypsyllinae

References [11]

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Turillazzi F., Mori E., Viviano A., Baratti M., Pucci C., Gobbi M., Sassera D, Bisaglia B., Romeo G., Lombardo A., Mariacher A., Domanico M.G., Roversi P.F., Mazza G. 2024 Beavers are not alone: parasitic assessment of released Eurasian beavers in Central Italy. Mammal Research 69 33–41. https://doi.org/10.1007/s13364-023-00715-0

Yavorskaya M.I., Jałoszyński P., Beutel R.G. 2022 A unique case of commensalism: The beaver beetle Platypsyllus castoris (Leiodidae, Coleoptera) and its morphological adaptations. Journal of Morphology 284: e21532. https://doi.org/10.1002/jmor.21532

Additional information

Received: 26 February 2026 · Accepted: 5 March 2026

Editor: Kal Ivanov

Conflicts of interest:
No potential conflict of interest has been reported by the authors, reviewers, or subject editor. As members of the editorial board, Nikolay Simov, Mario Langourov and Ilya Acosta-Pankov withdrew from discussions and decisions on the manuscript.

Authors’ contributions (using CrediT ↗):
Rostislav Bekchiev: conceptualisation, data curation, writing—original draft; Nedko Nedyalkov: methodology, writing—original draft; Rumyana Kostova: conceptualisation, visualisation, writing—original draft; Nikolay Simov: project administration, writing—review and editing; Mario Langourov: writing—review and editing; Ilya Acosta-Pankov: writing—review and editing.