Palynological characterization of a diverse desertic ecosystem: the Peruvian Lomas

Abstract

The Pacific coastal Peruvian landscapes are dominated by desert and dry-forest biomes, which have undergone shifts in extent and floral composition in response to Plio–Pleistocene climatic fluctuations. Within this context, the coastal Lomas develop as seasonal vegetation patches, renowned for their high endemism, rich floral diversity, and essential ecosystem services. Despite growing within the desert biome, the Lomas exhibit characteristic elements and vegetation structure typical of a dry-forest biome, evidencing an active species migration between xeric biomes. However, assessing the historical evolution of this arid flora and, by extension, the coastal desert landscape, presents challenges. The scarcity of continental sedimentary records and a lack of extended and well-described palynological references impede these efforts. In response to this, our study offers a thorough morphological review of the Lomas palynoflora, encompassing over 194 genera from 76 families, representing approximately 80% of the known Lomas flora. Our review includes at least one species per reviewed genus, featuring 37 palynomorphs from endemic species (18.5% of the studied flora). This palynological characterization is intended to serve as accessible reference material for investigating the historical and long-term evolution of the coastal dry flora. Furthermore, these findings facilitate the analysis of honeys and bee floral foraging patterns, as well as the study of animal–plant or human–plant interactions from middens and archaeological remains.