The work comprises an etymological and semantic analysis of micro-toponyms used in the south-east part of the Beskid Niski Mountains, derived from the names of plants and animals. The presented micro-toponyms reflect the pre-war ethnic variety of the researched area, and what follows – language diversity. Among the considered local names are forms belonging to the Polish language system, e.g. Leszczyny, Olszyny, Grabiki, Tarnie; the Lemko system, e.g. Berezynky, Wilszyny, Potik Wilchowy, Leszczackyj Potik, Werbina Łuka as well as Polish-Lemko contaminations, e.g. Pod Jablinką, Pod Jałyciami, Pieprzowa Hirka. The researched toponyms have been discussed in motivation and semantic groups created, for example, by topographic names, cultural names, metaphoric names, names which are ambiguous with regard to name origin, mixed or relational.