The researchers who did the work on the split, proposed American and Siberian..... Alström, P, Coiffard, P, Crochet, P-A, Doniol-Valcroze, P, Dufour, P & Robb, M. 2023. Molecular and acoustic evidence support the species status of Anthus rubescens rubescens and Anthus [rubescens] japonicus...