The flower of Pachycarpus galpinii has five sepals with pointed tips curving back slightly from the dark, shiny outside surface of the corolla. The sepals are greener than the upper margins of the corolla lobes above them, yellower than the leaves below them and hairy unlike both.
The cup-shaped corolla is dark red to purple-red or almost black, inside and out. Only the five strongly recurving corolla lobes that hide their tips are yellow-green, appearing hairless.
The five narrow, V-angled corona lobes are erect, becoming marginally taller than the corolla. They are also dark red to purple-red with shorter side appendages inside the cup. The style head, slightly depressed in the centre has membranous anther appendages over it (Leistner, (Ed.), 2000; iNaturalist).