Two new conulariid species, Conularia clarkei Babcock and C. paraguayensis Babcock from the Vargas Peña Shale, are the first Silurian conulariids to be described from Paraguay. They increase to three the number of Silurian species to be described from South America. The concept of Conularia Miller in Sowerby, 1820, is emended. It includes as junior synonyms Conularia (Plectoconularia) Bouček, 1939, Diconularia Sinclair, 1952, and Yangoconularia Xu and Li, 1985. The age of the Vargas Peña Shale has long been disputed, but conclusions based on organic-walled microfossils indicate an Early Silurian (Llandoverian) age for the unit.