2026-04-13 ワシントン大学（UW）
The researchers compared a jaw fragment from Galanthis baskini (top) to a complete mandible of the least weasel (bottom). A European cent is shown for scale. Photo: Alberto Valenciano
＜関連情報＞
- https://www.washington.edu/news/2026/04/13/a-fossil-of-a-new-carnivoran-species-effectively-doubles-the-evolutionary-history-of-the-weasel-family/
- https://onlinelibrary.wiley.com/doi/10.1111/pala.70055
イタチ科動物（哺乳綱、食肉目）の最古の証拠は、イタチ亜科が中新世に起源を持つことを示している Oldest evidence of a weasel reveals a Miocene origin of the Mustelinae (Mammalia, Carnivora)
Alberto Valenciano, Qigao Jiangzuo, Chris J. Law, Juan Abella, Diego Sánchez-Hernández, Andrés Fernández-Reyes, Luis Alcalá, Jorge Morales, Daniel DeMiguel
Palaeontology Published: 13 April 2026
DOI:https://doi.org/10.1111/pala.70055
Abstract
Weasels are among the most widespread small carnivores, playing a key role in extant Holarctic ecosystems by preying on other small vertebrates. Despite their substantial diversification during the Pleistocene, the evolutionary origins of these species before this period remain poorly understood. The most widely accepted view is that the oldest known true weasel, Mustela, dates from the Pliocene (4–3.5 Ma) of central Europe. A newly discovered species of a weasel-like mustelid, Galanthis baskini gen. et. sp. nov. from Las Casiones (Spain), demonstrates a Late Miocene (6.56–6.26 Ma) origin for Mustelinae, which is consistent with molecular divergence estimates for Mustelinae. Galanthis baskini emerges as the most basal member of the subfamily, confirming a small size (134.55 g) from the beginning of its evolutionary history. These findings shed light on the early evolution of Mustelinae and show that small forms already existed in the Late Miocene. In addition, Proputorius minimum, a related mustelid from China, is reclassified as Zdanskyictis gen. nov., which is closely related to the subfamilies Lutrinae and Ictonychinae. Galanthis and Zdanskyictis highlighting the key role of Eurasia in the evolution of the Mustelidae during the Miocene.
