Pantropical weed from a Neotropical origin. Known as Blue Snakeweed, and by names such as Rabo de Zorro in Spanish. Used against Malaria in folk medicine.
Despite having Java its name, this species in native to eastern Africa, where it is known as Musukudu. It has been widely planted under names such as Lemon Bush. Photo from near Mbeya, Tanzania.
Known as Margarita Puzo locally and as Peruvian Mock Vervain in English. Native to Peru, Bolivia, Paraguay and northern Argentina. Photo from near Sta. Cruz, Bolivia.