We describe a new species of Ischnocnema from upper montane rainforest in La Paz, Bolivia. Unlike its congeners, the new species possesses notched ungual flaps, a short dorsolateral fold, and a small axillary gland. The new species resembles I. sanctaecrucis and is the third species of Ischnocnema known from Bolivia. UNTIL the 1970's, the genus Ischnocnema was represented by I. quixensis from the Upper Amazon and I. verrucosa from the Atlantic rainforests of Brazil. Recently, addi-tional species of Ischnocnema have been dis-covered in the Andean foothills. Lynch (1974) described I. simmonsi from the Cordillera del Condor, Ecuador, and Duellman (1990) dis-covered I. saxatilis in San Martín, Peru. Harvey and Keck (1995) first reported the genus from Bolivia when they described I. sanctaecrucis from cloud forests of Parque Nacional Amboró , Santa Cruz. Ischnocnema verrucosa has rarely been collected (Lynch and Schwartz, 1971) and is known only from the Atlantic rainforests of Brazil. Duellman (1978, 1990), Lynch (1972, 1974), Lynch and Lescure (1980), and Toft and Duellman (1976) published distributional data for I. quixensis in upper Amazonia. Recently collected specimens extended the range of this species to Cusco and Madre de Dios in south-ern Peru (Harvey and Keck, reported I. quixensis from Pando in northern Bolivia, but did not give more precise locality information (the speci-men came from San Sebastian; Reserva Tahua-manu; 11.407228 S, 69.01758 W, S. Reichle, I. De la Riva, personal communication). Additional specimens of I. sanctaecrucis were later found in Cochabamba (Reichle, 1999), and Reichle (1999) described this species' call. During the last ten years, M. B. Harvey and field parties from the Colecció n Boliviana de Fauna made several expeditions to the Serra-nía de Bella Vista, a humid ridge covered in upper montane rainforests in the foothills of La Paz, Bolivia. An earlier paper (Harvey and Noonan, 2005) reported centrolenids collected at this locality. Among the rocky seeps in rainforests on the lower slopes of the serranía, Harvey collected specimens of a distinctive new Ischnocnema, which we describe herein.