Cymbidium aloifolium (Orchidaceae) and Its Allies

Abstract

In The Orchids of Thailand (1961) Seidenfaden & Smitinand referred to the difficulty they found in identifying a number of Cymbidium species. They wrote of one group in particular: 'It is not possible for us on the basis of our own material and the available literature to solve the complicated problems around the old C. aloifolium-C. pendulum group'. These problems were indeed not new. In the early part of this century R. A. Rolfe, working at Kew, attempted to clarify a confused situation in two articles in the Orchid Review (1915, 1917). In the first, he tried to show how the confusion between C. pendulum (Roxb.) Sw. and C. aloifolium had arisen. In the second, he discussed the relationship between C. aloifolium, C. pendulum, C. bicolor, and C. finlaysonianum, all of which he considered distinct species. He thereby rejected the view held by J. D. Hooker (1891) that C. aloifolium and C. pendulum should be united and, in order to resolve matters, distinguished an additional species which he named C. simulans. Throughout, Rolfe appears not to have questioned the original separation of C. aloifolium and C. pendulum by Swartz (1799). The purpose of this discussion is to examine, in particular, that early nomenclature and consider the implications of any conclusions reached. The principle names in this group of closely related Cymbidium species are: C. aloifolium, C. atropurpureum, C. bicolor, C. finlaysonianum, C. pendulum, C. pubescens and C. simulans. Although neither C. atropurpureum nor C. finlaysonianum had a trouble-free early passage (Rolfe 1903, 1917), these two appear to be accepted as distinct species by modern authors (Holttum 1964, Backer & Bakhuizen 1968), who usually distinguish them by the size of the flowers, the colour of the sepals and petals, the shape of the side-lobes of the lip, the shape of the keels and the breadth of the leaves. To answer some of the questions about the remaining names the starting point seems to be a consideration of the earliest of these: C. aloifolium and C. pendulum. Swartz himself thought that the latter was 'very much like' the former, apparently separating them only by whether the scape was erect or pendulous. His difficulty was that these two species had been based by Linnaeus and Roxburgh on drawings rather than plant material, as King & Pantling (1898) and later Rolfe (1917) pointed out. C. aloifolium was based on very similar drawings in two early books: Rudbeck's Campi Elysii (1701) and Rheede's Horti Malabarici (1703). Johannes Commelinus appears to have had a hand in the entries in both works, but as that in the latter was accompanied by a very full description under the heading 'Kansjiram-Maravara', it seerris as though the later publication was taken as definitive. C. pendulum was based