The thin, laminar to low domical, encrusting stromatoporoid Pulchrilamina spinosa is reported from the Tremadocian—Floian in Hubei and Guizhou provinces, South China. The Chinese Pulchrilamina appeared earlier (late Tremadocian—early Floian) than North American equivalents (early Floian), which possess large domical forms and are the main framework-builders. Pulchrilamina appeared much earlier than the observed diversification of other stromatoporoids. These skeletal reef-builders thus provide excellent clues for understanding the initial evolution of the stromatoporoids and the subsequent development of the skeletal-dominated (especially stromatoporoid-dominated) reefs that reached their first acme in the late Middle—Late Ordovician.