Rhodochiton is a genus of flowering plants within the family Plantaginaceae, native to southern Mexico and neighbouring Guatemala. They climb by means of twining leaf stalks. One of the three species, "Rhodochiton atrosanguineus", the purple bell vine, is grown as an ornamental plant. All three species are sometimes included in "Lophospermum".
There are two other species of plants in the Rhodochiton genus besides Rhodochiton atrosanguineus.
It's definitely correct because the sentence says "one of three species...etc", so there must be three species in that genus, two of which are not the species listed. It's difficult because the system might not understand how species/genus classification works.