Paphiopedilum delenatii var dunkel may be called Paphiopedilum delenatii forma vinicolor in some references. When it was first introduced it was called ‘dunkel’, which is German for dark so we are using that name. The term is certainly accurate as this is the darkest form of the species. The flowers have intensely colored pouches and even the foliage is darker than the type form. Jay’s online encyclopedia lists it as f. vinicolor in his references.
This is also one of the few Paphiopedilum species that is fragrant. A nice bonus to go with the attractive flowers. This species blooms from spring into early summer. We sometimes see flowers in the fall but it is unusual. Typically you will get one flower per spike, but it can produce two flowers from time to time.
This is a good form of the species to use for hybridizing. Hybrids like Ho Chi Minh and Magic Lantern made with dunkel instead of type have much more intense color. That makes this plant highly desirable for hobbyists and breeders alike.
This form of the species grows a little more slowly than the type. This is more of an issue with small seedlings. Mature plants grow and flower reliably. Just grow them like most mottled leaf Paphs as we describe here.