Exploring the distribution range and conservation priority areas of the evolutionarily significant genus Schlechtendalia Less. (Barnadesioideae: Asteraceae)

Schlechtendalia luzulifolia is an evolutionarily and ecologically distinctive lineage within the Barnadesioideae subfamily (Asteraceae). It is restricted to the grasslands and savannas of southern Brazil, Uruguay, and eastern Argentina, where it occupies open habitats such as rocky outcrops, native grasslands, and coastal sandy soils. These ecosystems are highly vulnerable to human activities and remain poorly represented within existing protected-area networks. By integrating field surveys, historical herbarium records, and species distribution models, we identified areas with different levels of environmental suitability for the species and evaluated their overlap with protected areas, Key Biodiversity Areas (KBAs), nationally designated biodiversity priority areas, and levels of human impact. Following IUCN guidelines, we also conducted a preliminary assessment of the species’ conservation status. Our results revealed two primary areas of high suitability: one in the highland grasslands of the Araucaria Moist Forest ecoregion, and another across the extensive grasslands of the Uruguayan savanna ecoregion. Although the most suitable areas more frequently overlapped with KBAs, we detected no differences among suitability classes in terms of formal protection within protected areas, nationally designated priority areas, or levels of human impact. The preliminary conservation assessment categorized S. luzulifolia as Least Concern. Nevertheless, the limited protection of its habitat and ongoing land use pressures highlight the importance of monitoring its distribution in order to ensure the long-term conservation of this distinctive Asteraceae lineage and the grasslands it inhabits.