Timarcha lugens (Chrysomelidae) is a wingless leaf beetle endemic to the high mountains of the Sierra Nevada (Spain). The genus Timarcha comprises a group of herbivorous species, widely distributed in Europe, Turkey, North Africa and Western North America, which inhabit a broad range of habitats, including high mountains, humid forests and sandy coastal areas. In the Iberian Peninsula, Timarcha is represented by more than 25 species, some of them inhabiting montane regions. In the Sierra Nevada, this genus is represented by four species, although only three of them, T. lugens, T. insparsa Rosenh., and T. marginicollis Rosenh., occur over altitude. While T. lugens and T. insparsa are endemic species of the Sierra Nevada mountains, T. marginicollis is also present in other mountain ranges in southern Spain. T. lugens distribution area spans from above sea level, being the most abundant chrysomelid at these high-altitudes.