Selbyana 28(2): 117-122.2007. DENDROBIUM SWARTZ SECTION HERBACEA KRANZLIN (ORCHIDACEAE) HOWARD P. WOOD, M.D. Associate in Botany, Academy of Natural Sciences of Philadelphia, Philadelphia, PA 19003, USA. Correspondence: 3300 Darby Road C-802, Haverford, PA 19041, USA. Email: [email protected] ABSTRACT. Dendrobium Sw. Section Herbacea Kraenz!. is revived for two Asian species, Dendrobium herbaceum Lind!. and D. parcum Rchb.f. Definitive characters are branching, deciduous habit; short, few­ flowered racemes arising from the branches, often apparently terminal; and small simple flowers with decurved saccate mentum. The type species is D. herbaceum. There appears to be a third, unidentified, species. Key words: Orchidaceae, Epidendroidere, Dendrobiinre, Dendrobium herbaceum, D. parcum, D. ramosis­ simum, section Herbacea Two species of Dendrobium have never fit 1981, Joseph 1987). It is evidently common in well into any of the sections of the genus in the Western Ghats, although I have not seen or current use. These are Indian D. herbaceum read about its cultivation in the West. The best Lindl. (1840) and Southeast Asian D. parcum drawings among the above sources appear in Rchb.f. (1866). These plants are similar and Pradhan (1979) and Abraha= and Vatsala very distinctive, with multiple upcurving, linear (1981). to fusiform branches, leafy on the terminal Dendrobium herbaceum may reach 90 cm (35 branches or branchlets only, and usually decid­ inches) in height. The flower has lip down­ uous before flowering. The leaves are acumi­ curved and constricted near the middle, with the nate; the roots are smooth. Short racemes bear proximal edges slightly rolled upward, forming up to about 5 flowers, each 1 cm or less in di­ rudimentary side lobes. The blade is ovoid, ameter. The inflorescences usually appear to be coming to a blunt point. The flowers are de­ terminal on the leafless branches, but may also scribed as green (Lindley 1840), greenish-white be lateral. The flowers have a deflexed, saccate (Santapau and Kapadia 1966) and pale yellow mentum and prominent lip. In D. parcum the (Joseph 1987). Abraham and Vatsala (1981) de­ column is short, rostellum bifid, anterior surface scribe them as white with a yellow lip (FIGURE of the column foot hollowed and broadened 3). As discussed below, some authors may be around and below the orbicular stigma. The pol­ referring to a third species. linia are unusually short and broad for the genus. Apparently unaware of Lindley's taxon, Rob­ Drawings of D. herbaceum, in the references cit­ ert Wight, surgeon-botanist for the East India ed (FIGURES 1, 2, 3), show similar features. The Company in Madras, described from dried ma­ only obvious distinguishing character among the terial a (misspelled) D. ramossissimum ("very species, including an unnamed entity discussed branched") (FIGURE 4). The description and below, is lip structure. drawing (FIGURE 5) in his leones are labeled, t. Dendrobium herbaceum ("yellow-green"), 1648 (Wight 1852). Below, following Lindley, I described by John Lindley (1840), is endemic to refer to his drawing as "R. W. t. 1648." The the peninsula of India. Although reported from specimen, now in Wight's herbarium at Kew, other locations, this species typically inhabits the had been collected by Jerdon in the Coorg (now Western Ghats, the range of mountains extend­ Koorg) jungles in the Western Ghats, midway ing the length of the west coast of the peninsula. down the peninsula. Wight's detailed drawing Lindley sketched the lip shape clearly on his shows the distinctive lip of D. herbaceum. He type sheet (FIGURE 2), where he noted that the describes the flowers as yellow. specimen had been imported by the firm of Lod­ Lindley's sheet of D. ramosissimum (he cor­ diges from the "East Indies," a term which in rected the spelling) is in his own herbarium, now those days included India. This species is dis­ kept separately at Kew (FIGURE 6). It contains cussed, with drawings but without photographs, not Wight's but two later specimens. Indicating in subsequent literature on the orchids of India that he (incorrectly) considered it a type, Lindley (Hooker 1890, Fischer 1928, Santapau & Ka­ attached a label across the base of the stem of padia 1966, Pradhan 1979, Abraham & Vatsala the plant on the right, marked "R. W. Ie. 1648" 117 118 SELBYANA Volume 28(2) 2007 FIGURE 2. Dendrobium herbaceum Lindl., type sheet drawing, enlarged detail. FIGURE 1. Dendrobium herbaceum Lind!. type Wight described and figured. In addition, Abra­ specimen; published with permission from The Royal ham and Vatsala (1981) show, for one of the two Botanic Gardens, Kew. flower specimens of "D. herbaceum" in their sketch, the lip distally expanded and grooved. This flower resembles that of the Ker plant. and noted its ongm as "Dalzell, S. Concan Lindley, seven years after Wight's description, R.160, 52 Herb J. E. Stocks." Labeling this commented on D. ramosissimum: "This is very specimen in a manner he reserved for types near my D. herbaceum (Lindley 1840, Bot. Reg. seems to be one of several uncharacteristic mis­ 1840, misc. 153), but the flowers are white with takes in Lindley'S late work on the Dendrobi­ a yellow lip, not white tinged with green; the lip inae, including the 1859 paper. These may be itself is longer and more fleshy, and the flowers early signs of his fatal dementia. His mental are considerably smaller. I have examined fresh powers failing, he retired from his professorship specimens out of Mr. Bellenden Ker's garden in 1861, had a "breakdown" in 1862 and died from Dharwar." (Lindley 1859). Dharwar, now in 1865 (Stearn 1991, 1999). Hubli-Dharwar or Hubli, is a city 400 kIn (250 Although Lindley (1859) kept the two taxa mi) southeast of Bombay, east of Koorg. For the separate on unclear grounds, the type sheets in­ (erroneous) type reference, in his 1859 paper dicate that D. ramossissimum Wight is a syno­ Lindley writes, "S. Concan, Dalzell in hb. nym of D. herbaceum Lindl. I am retaining both Hooker. (Stocks, 52)." Thus the right-hand spec­ spellings, Wight's and Lindley's, for purposes of imen on Lindley's sheet, Stocks 52, came from clarity, since two taxa seem to be involved and, the Hooker herbarium, and Lindley seems to indeed, the name in either case is illegitimate. have incorrectly considered it his lectotype for The plant on the left side of Lindley's sheet D. ramossissimum Wight. The Ker plant on the for Dendrobium ramosissimum is marked, "H. left and in the drawing is obviously one of those B .. Ker, Dharwar." Adjoining it in the center, and which Lindley received alive and described in similarly labeled, is a drawing of a white flower the quotation above. Thus I believe that it rep­ with a straight, fleshy, rounded lip. The blade is resents a still-undescribed species, which I will yellowish brown with a medial groove extending call "D. ramosissimum sensu Lindley, non to the tip. The rudimentary sidelobes are slightly Wight." uprolled. This plant is certainly not the taxon George Bentham and J. D. Hooker (1883), WOOD: DENDROBIUM SECTION HERBACEA 119 FIGURE 3. Dendrobium herbaceum drawing in Abraham and Vatsala "1981." Introduction to Orchids. Fig. 91, p. 367. Flower images D and H resemble Dendrobium ramossissmum sensu Lindley. when forming a new subsection Ramosissima with a branching stem like D. ramosissimum" (see below), cited only Wight leones t. 1648, (Reichenbach 1866). I have not seen the type indicating D. ramossissimum as the only species. sheet, which is presumably in Reichenbach's Hooker later, however, in his work on Indian or­ herbarium in Vienna. Seidenfaden has discussed chids (1890), reduced D. ramossissimum to syn­ this species, with a drawing and flower photo­ onymy with D. herbaceum. He did not refer to graph, in his treatment of Dendrobium in Thai­ the possible third entity on the Lindley sheet. land (1985). Nunt (1999) has found it in several The later authors listed above have followed parts of Myanmar. him. Since World War II, native orchids have not Dendrobium parcum has long been exported been widely exported from southern India, and from Thailand. I have grown and photographed these plants are not in general cultivation over­ it. The lip is not constricted, and there are no seas. side lobes. The blade gently expands distally, Dendrobium parcum (meaning "scanty, mea­ with a squarish and slightly ecarinate tip. The ger"), the second established species in section flowers are concolor dull yellow, the lip some­ Herbacea, inhabits Myanmar (Burma), Thai­ times variably speckled with purple. Seidenfad­ land, and Vietnam, and presumably also inter­ en (1992) considered the Vietnamese D. parcoi­ vening Cambodia and Laos. After the conquest des Guillaumin (1955) synonymous. At issue are of Burma, the indefatigable Rev. C. S. P. Parish, only the lip markings, inconstant in both taxa. British chaplain at Moulmein, found this species A fifth taxon in the section is D. listeroglossum in the southern peninsular area called Tenasser­ Kraenzl. (1892), which the author later (Kran­ im. The plant was flowered in England by Low zlin 1910) reduced to synonymy with D. par­ & Co., who submitted it to H. G. Reichenbach cum. for identification. Its name fits his comment in George Bentham and J. D. Hooker (1883), in the description: "a very poor-looking specimen their reclassification of Dendrobium, created a 120 SELBYANA Volume 28(2) 2007 FIGURE 4. Dendrobium ramossissmum sensu Wight, detail from type specimen. FIGURE 5. Dendrobium ramosissimum-Wight detail from type drawing. WOOD: DENDROBIUM SECTION HERBACEA 121 FIGURE 6. Dendrobium ramosissimum [sic] Wight type drawing. "Dendrobium ramossissimum" sensu Lind­ ley. Lindley's drawing of specimen Stocks 52. subsection Ramosissimae within section Stach­ land (1985) and Indochina (1992) reluctantly yobium.