A new species of theraphosid spider, Citharacanthus meermani sp. nov., is described. It was collected in the foothills of the Mountain Pine Ridge and the Vaca Plateau, Cayo District, Belize. It is distinguished from congeners by filiform plumose setae on the basoprolateral faces of both trochantera and femora I-II, and the presence of five prominent keels on the apical division of the male embolus.