German botanist (1818–1883).
Heinrich Poselger (25 December 1818 – 4 October 1883) was a German botanist who specialized in studies of succulent plants. From 1849 to 1851 he collected plants, especially cacti, along the U.S.-Mexico border, and in the process took part in the United States and Mexican Boundary Survey. His collections of cacti were sent to the herbarium at Jena. He was a resident of Berlin, where he maintained an impressive collection of succulents. He is the taxonomic authority of numerous species within the family Cactaceae, and has a number of cacti species bearing his name, a few examples being Corypha