Some species have compound leaves in stead of simple leaves: Trichosanthes elmeri and Trichosanthes trifolia.
Trichosanthes elmeri has palmately compound leaves (spot-character 49)
Trychosanthes costata (syn. Gymnopetalum chinense) has ridges fruits (spot characters #110)
Trychosanthes scabra has a rough leaf surface.
Gymnopetalum is a synonym of Trichosanthes.