Abstract Aim To determine if the distributions of lizard species from Seasonally Dry Tropical Forest (SDTF) enclaves within the Cerrado biome in central Brazil are associated with the Tropical Seasonal Forests Region, a recently proposed phytogeographic unit of South America, corroborating the existence of a Pleistocenic Arc of SDTFs. Location SDTF remnants in the Paranã River valley, municipality of São Domingos, Goiás, Brazil. Methods Lizards were extensively sampled using haphazard sampling, funnel traps, and pitfall traps with drift fences during four expeditions. The composition of the SDTF lizard assemblage was compared with those from other South American phytogeographic regions (Caatinga, Cerrado, Chaco, Llanos, and the dry forests of Colombia and Bolivia), based on the literature and our own unpublished data. Results The SDTF lizard assemblage contained 20 species, including 11 species with extensive distributions among the regions considered, seven species shared exclusively with Cerrado localities, a single species shared exclusively with other SDTFs, and one endemic species. The presence of Lygodactylusklugei (Smith, Martin & Swain, 1977), presumably endemic to the Pleistocenic Arc formed by the Tropical Seasonal Forests Region, considerably extends the known distribution of this species, suggesting historical connections between Caatinga and Cerrado SDTF enclaves. Main conclusions The composition of the lizard assemblage in Cerrado SDTF enclaves seems to corroborate the recent proposal that the SDTF should be recognized as a phytogeographic unit (or dominium). The presence of disjunct populations and endemic species highlights the urgency of considering the uniqueness of the Paranã River valley SDTFs and the importance of its conservation.