Vol. 77 2025

ARTICLES

Variations in Coat Colouration of the Romanian Hamster (Mesocricetus newtoni Nehring, 1898) with the First Description of a Black (Atypical Melanistic) Form

Yasen Gensuzov*, Yordan Koshev

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*Institute of Biodiversity and Ecosystem Research at the Bulgarian Academy of Sciences, 1 Tsar Osvoboditel Blvd., 1000 Sofia, Bulgaria; ¹E-mail: gensuzi@gmail.com, ²E-mail: bgsouslik@gmail.com

https://doi.org/10.71424/azb77.4.002954

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Abstract

The Romanian hamster (Mesocricetus newtoni Nehring, 1898) is an extremely rare rodent, endemic to Bulgaria and Romania and listed as Vulnerable by the International Union for Conservation of Nature (IUCN). The article reviews variations in fur colouration in individuals caught by the authors, as well as in museum collections, scientific publications and photographs on websites and social media. We observed variations in the size and shape of the black chest patch, variations in the length of the black stripe on the cheeks and others. A black (atypical melanistic) form was described for the first time in M. newtoni. That variant was rare, occurring in only 0.6% of the total 167 individuals examined or described. We believe that the reduction in population abundance, which, according to literature data, has decreased by about three times, leads to a reduction in genetic diversity, a high level of inbreeding and the appearance of similar melanistic specimens.

Key words

Dobrudzha hamster, collections, melanism, population decrease, Bulgaria

How to Cite
Gensuzov Y. & Koshev Y. 2025. Variations in Coat Colouration of the Romanian Hamster (Mesocricetus newtoni Nehring, 1898) with the First Description of a Black (Atypical Melanistic) Form. Acta zoologica bulgarica 77 (4): 515-521.

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