Lymanbensonia choquequiraensis, a new species from Cusco, Peru, is described and illustrated. This species is only known from the vicinity of the archaeological site of Choquequirao. L. choquequiraensis is compared to L. micrantha and L. crenata. The stems resemble L. micrantha (the geographically closest species from Puno, Peru) but differ in having four angled stems rather than two or three ribs. The flowers of L. choquequiraensis are much smaller than L. micrantha, of equivalent size to L. crenata but with significant morphological differences. This new species increases the number of Lymanbensonia species currently known to five.