Abstract
Stylotrichium is a small genus in which all the five species are restricted to the rocky field vegetation (campo rupestre) in Chapada Diamantina, Bahia state, Brazil. From recent field collections in the area we have recognized a new species based on morphology. Stylotrichium hortensiae is distinguished by laminae oblanceolate to oblong (3.5–8 × 1–3 cm), greater number of flowers (35–45), anther connective appendage as long as wide, style 6.5 mm long, and pappus 1–1.5 mm long. A species description, illustrations, a key to the species, comments, and a distribution map are provided.