trifasciata vs.laurentii: Part.II
Which came first: the chicken or the egg? Which is the "good" species: trifasciata or laurentii?
In Part.I I tried to show You that S.trifasciata Prain is not a good species and that this worldwide known ornamental plant is still waiting for its taxonomic recognition. Now let s give a look to the plant we know as S.trifasciata var.laurentii (De Wild.) N.E.Brown.
It is a variegated form, with broad yellow stripes along leaf margins. These are layers of cells with a different genetic pattern from the green ones (chimeric tissue).
We don t know if it is the result of a single or of many mutations that occurred to an all-green plant. We don t find many variegated plants in the wild, as the lack of chlorophyll is an obvious handicap in the struggle for life.
A single clump of this striking plant was discovered by the Belgian botanist Emile Laurent in a garden near Stanleyville in Belgian Congo, the very "heart of darkness" of the African continent. Laurent didn t survive his explorations and died aboard of a steamboat while returning home in 1904. His cousin Marcel Laurent arranged the 3,500 collected specimens after his death. Two living specimens ( "deux pieds" ) were successfully grown in the Botanic Garden of Bruxelles, while Emile De Wildeman was the Director. A cutting taken from these plants was sent to Kew Gardens in 1909.
Emile De Wildeman never travelled to Africa, but safely worked as "Conservateur"of the Garden, identifying and describing more than 1,000 of the plants collected by Laurent. He was soon fascinated by this new, colourful S. and described it as a new species on April 20th, 1904 (Revue de Cultures Coloniales, tome XIV, Nr.147, 20 Avril 1904, pag.231). Then, he described it again in his extensive article on the African species of S. (Les Sansevieria africains, in: "Notices Plantes Utiles...du Congo", pag.628, 1905. He described it for the third time in : "Mission Emile Laurent" Vol.II, pag.45, 1907, accompanied by two small pictures. In the meanwhile, his colleague, Louis Gentil, had republished the same description together with a beautiful, two pages size, hand coloured illustration (by M.lle Helene Durand, daughter of the Director of the Botanic Garden) in : Revue de l Horticulture Belge et Etrangere, vol.XXX, pag.169, 1904. A beautiful (black and white, of course) photo of the plant was published on the world famous "Gardeners Chronicle" on May 29th, 1909 (pag. 347) and republished on August 22nd, 1914 (pag. 144). A dried specimen taken from the mother plant is in the Kew Herbarium (RBGK: K000255745). A hand written note signed by N.E.Brown says: " Sansevieria laurentii De Wildem.! From a portion of the type plant! Received from Brussels Botanic Garden in 1909. Kew Gardens April 13.1910". Please note that the exclamation mark, in a taxonomic writing, means the author has personally seen the specimen. As one only plant was found by Laurent, and as everyone knows that "laurentii" cannot be propagated true but from rhizome cuttings, this is undoubtedly the type plant (well, so ANY "laurentii" plant in the world is the type plant, indeed).
I see no problems in making a species of a plant only known from cultivated specimens, and not growing in the wild. This happened to many well known plants, i.e. Ginkgo biloba, Capsicum pubescens, Vanilla tahitensis, Cycas aenigma, Zantedeschia elliotiana, Corypha taliera etc. Not to mention most of the present-day crop plants. I am waiting a reply by some expert: my aim is not to stir a quarrel, but just to show You that taxonomy is a living science and a still unexplored world full of mysteries.