Homo helmei is one of many human species that has failed to gain widespread recognition. Textbooks tend to either mention it only in passing, or not at all. The species was assigned to the single partial skull which was recovered in 1932 by Professor T.F. Dreyer from the depths of the hot spring at Florisbad, some 50km (30miles) from Bloemfontein, South Africa. The skull comprises the right side of the face, most of the forehead and portions of the roof and sidewalls. A single upper right wisdom tooth was also found with the skull and in 1996 two small samples of enamel from this were found to be 259,000 years old using a technique known as electron spin resonance. In 1935, Dreyer described the find as Homo helmei to mark its distinctiveness from other fossil Homo sapiens. Homo helmei is not widely accepted, largely because it is still known only from this one specimen and it is usually “lumped” into Homo heidelbergensis ("archaic Homo sapiens").
The etymology of Homo helmei is something I have yet to find listed in any textbook and it took a good deal of digging around on the internet until I eventually came across the website of the National Museum, Bloemfontein, which provided the following insight:
The town of Florisbad is named for Floris Venter, a local entrepreneur who in 1912 enlarged the pools at the spring for use as a spa. Later that year an earthquake caused a new spring to open up, revealing stone tools and fossils. During the late 1920s, zoologist Professor T.F. Dreyer and his assistant Ms. A. Lyle carried out excavations in the vicinity of the spring. These were funded by Captain R.E. Helme and produced further quantities of animal fossils. The story goes that Venter feared loss of revenue if his baths were temporarily drained and Dreyer and Ms. Lyle had to wade around in the waters and grope for bones. On one such occasion, Dreyer plunged his hand into the spring deposits underwater and – rather in the manner of Little Jack Horner – pulled out part of a human skull, with his fingers stuck between its eyes!
This was the find later described as Homo helmei - it simply means "Helme's Man" and was named for Capt. Helme, whose funding had made the discovery possible.