This is a dark red to brown species of Cosmos, native to Mexico. Sadly it has been extinct in the wild for over a hundred years. The species survives today as a single non fertile clone, which was created in 1902 by vegetative propagation. The flowers which are produced by the plant are a rich deep red to brown colour and grow to about 3-4 cm in diameter. The flowers have a lovely vanillin fragrance in the summer (also found in vanilla beans, some coffee beans and some cacao beans), which also makes it a wonderful ornamental plant. This plant isn't just the colour of chocolate it smells like it too!
Cosmos atrosanguineus is unique because every individual in cultivation today stemmed from the very same original plant introduced in 1902. .All others have become extinct in heir native range of Mexico. Because cosmos are not self fertile there are no existing seeds for chocolate cosmos in existence, preventing the production of any seedlings. It is often referenced in scholarly works dedicated to preserving and protecting botanical genetic diversity.