What is Sansevieria patens?

The 2004 offering of the I.S.I. (International Succulent Introductions) included what was referred to as “the type clone” of Sansevieria patens (Trager, 2004). This species was described by N. E. Brown (1915) from a plant growing at Kew, with the comment “Origin unknown, but probably British East Africa”. British East Africa is an early name for what is now known as Kenya. My interest was aroused because the identity of S. patens is still a bit of a mystery, and I am not satisfied that I have found anything representing it in Kenya. Clonotype material would be useful, but can the I.S.I. plant really have originated from the Kew specimen on which Brown based his species nearly 100 years ago?. In the I.S.I. announcement the origin of their plant is traced back to 1958, when it was introduced to the U.S.A. by the U.S. Department of Agriculture
(Trager, 2004). The provenance of the I.S.I. plant is given by Trager as:
1958: USDA (no. 254414) ⇒ Koko Crater, Foster Botanical Garden, Honolulu (no. FBG 66.649) ⇒ 1981: Alice Waidhoffer ⇒ Ed Eby ⇒ Dave Grigsby ⇒ John Bleck ⇒ Huntington Botanical Gardens (no. HBG 62111, offered as I.S.I. 2004–35). An earlier publication by Rossovich (1992) brings a little confusion into the story. Whilst Trager states that the USDA imported the plant in 1958 and cuttings from there went to the Foster Botanical Garden in Honolulu, apparently the record card in the Foster Botanical Garden says that the plant there was obtained from Lucknow Botanic Garden in 1965, yet the card shows USDA as the source, with the USDA accession number. Puzzled? So am I. Perhaps this means that the USDA obtained their plant from Lucknow in 1958, and sent it to Honolulu in 1965. Rossovich also states that Waidhoffer saw the plant in Honolulu but it was Eby who carried a plant from Honolulu and propagated it for distribution to growers. Whatever may be the correct details of how the species got around in the U.S.A., the implication is that the plants in cultivation were obtained, by an unspecified route, from Brown’s plant at Kew. The latest list that I have of sansevierias in the living collection at Kew, obtained in July 2002, includes only three species with accession dates before 1915, and S. patens is not one of them. It would be very interesting if the I.S.I. plant really is clonotype material and, if so, to know how it got from Kew to the USDA, via Lucknow or otherwise. I now have a rooted cutting of the I.S.I. offering in my garden near Nairobi, thanks to John Trager and Dr. Bob Webb. My next task is to see if I can match it with living material collected in the field in East Africa. However, firstly I must wait for the airmail size cutting (fig. 1) to grow to maturity. At that time, according to Brown, it should have leaves up to three feet long.