The Lower Devonian (Lochkovian) hexactinellid sponge Talacastospongia minima new genus new species is reported from the lower beds of the Talacasto Formation in the Argentine Precordillera. It represents the first Devonian sponge from South America and the best record in the paleobiogeographic context of the Malvinokaffric Realm, otherwise virtually devoid of spiculate sponges. This discovery provides some tentative insights on the age and oldest record of the Family Pileolitidae. The paleogeographical context for this new finding shows a high latitude setting with a notable scarcity of hexactinellid sponges recorded to date in Devonian Malvinokaffric basins, and the absence of calcareous spiculate sponges (heteractinids) and hypercalcified sponges (stromatoporoids, sphinctozoans).