586. DRACULA CORDOBAE Orchidaceae. Clare Drinkell

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1 586. DRACULA CORDOBAE Orchidaceae Clare Drinkell Summary. Dracula cordobae Luer from Ecuador is illustrated. Its taxonomy, relationships and distribution are discussed and a full description provided. With their high seed production, ability to travel long distances and to adapt to specialised habitats, orchids are one of nature s ecological pioneers. Pollination of a compatible flower may result in the production of thousands of dust-like seeds, increasing the possibility of mutations and perhaps the evolution of new taxa. The volcanic Ecuadorian Andes have remained constantly active and extensive areas of vegetation are regularly being destroyed and new habitats created, providing opportunities for colonization by orchids (Dodson, 2003; Tremblay, 2005 ). In addition to tectonic activity, there are many varying climatic and topographic conditions that have influenced the colonization and dispersal of orchids in Ecuador. These include the cold Humboldt and warm California currents which create exceptional fluctuations in climate unusual for an equatorial region; the position of the sun is nearly directly overhead throughout the year, causing minimal annual fluctuations in temperature; coastal regions are affected by seasonal rainfall; the east-west wind-flow and seasonal heavy rainfall on the east slopes of the Andes; elevation, which affects temperature and rainfall, created by the uplifting by the west-east sliding of the tectonic plates forming abrupt west-facing slopes in the western part of the Andes, and gentler east-facing slope in the eastern part. These and other factors have contributed to Ecuador having one of the world s richest orchid floras, estimated at 3784 known species ( Dodson, 2003 ). The genus Dracula belongs to subtribe Pleurothallidinae, which includes such diverse genera as Masdevallia, Pleurothallis and Stelis. It was established by Carlyle Luer in 1978 to include the 51 species previously referred to Masdevallia section Saccilabiatae. Three subgenera are currently recognized in Dracula, viz. Dracula, the largest with 5 sections including one subdivided into two subsections, represented by all but two species; Sodiroa solely represented by D. sodiroa (Schltr.) Luer; and Xenosia, solely represented by D. xenos Luer & Escobar. The Board of Trustees of the Royal Botanic Gardens, Kew Published by Blackwell Publishing Ltd, 9600 Garsington Road, Oxford, OX4 2DQ UK and 350 Main Street, Malden, MA 02148, USA 101

2 The name Dracula, translates from Latin as little dragon, and was chosen by Luer because of the dragon or bat-like appearance of the flowers ( Luer, 1993 ). Luer stated that if he had realised that Bram Stoker s fictional vampire character would have had such an influence on Twentieth Century culture, he would have chosen a different name ( Ferrusi, 1997 ). Species of Dracula, in common with Masdevallia, have short leafbearing stems (ramicauls) and long caudate sepals. The petals are highly reduced in both genera, the role of display taken over by the sepals. Dracula is distinguished from Masdevallia by a set of characters including thin leaves with a prominent, sharply dorsallycarinate midrib; sepals connate toward the base, pubescent within; petals short and thick; lip usually inflated, with elevate radiating nerves; 2 pollinia ( Hermans & Hermans, 1997 ). The open, pendent flowers of Dracula cordobae measure 12 cm in diameter. The periphery and tails of the sepals are intensively spotted red-brown, contrasting sharply with the creamy-white interior which is covered with long white hairs. The lip is white with a rounded, concave epichile and has denticulate margins and numerous, radiating lamellae. Vogel (1978) suggested that the amazing fungus-like lip epichile in Dracula imitates the inverted cap of a gilled mushroom, and that the flowers are pollinated by fungus gnats. These inhabit the dark, damp habitats favoured by species of Dracula. The gnats normally lay their eggs on mushrooms and do likewise on the flower mimics, being deceived by smell, sight and touch. Pollinia become attached to the hairy thorax of the gnats ( Vogel, 1978 ). The floral fragrance of D. chestertonii (Rchb.f.) Luer was analyzed by Kaiser (1993) and found to contain 1-octen-3-ol and 3-octanone and other minor components which produce a mushroom-like scent. Approximately 120 species and 2 subspecies are currently recognised in Dracula, 44% occurring in Ecuador, of which 73.6%, including D. cordobae, are endemic ( World Checklist of Monocotyledons, 2006 ). In the past 28 years 69 species and two subspecies of Dracula have been described, representing an average of 2.5 species per year. The current interest in Dracula and other members of the Pleurothallidinae is in large part due to the monumental publications of Luer. In addition, there has been considerable effort made to document the botanical diversity of Ecuador, helped by the construction of new roads into previously inaccessible areas. From 1931 to 1975, a total of 3187 herbarium collections on average per annum 102 The Board of Trustees of the Royal Botanic Gardens, Kew 2007.

3 Plate 586 Dracula cordobae ANDREW BROWN

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5 were made. Since 1975 the rate has increased to an average of collections per annum. This represents an increase of around 18 collections per 100 km 2 at the start of last century to more than 200 collections per 100 km 2 at its end ( Jørgensen, 1999 ). Draculas are found in moist, montane forests throughout the Western neotropics, from SE Mexico south to Peru. They are usually found as epiphytes in shady humid cloud forest, or as terrestrials on embankments, where they prefer rich, well-drained soils. Most species occur at elevations between 500 and 2500 m. D. cordobae is unusual in being found at relatively low elevations between 500 and 1000 m in the Ecuadorian provinces of El Oro, Los Ríos, Pichincha and Zamora-Chinchipe ( TROPICOS, 2006 ). The population of Ecuador increased from under 4 million in 1957 to over 10 million in Building, road construction, and exploitation of natural resources such as petroleum extraction have Dracula cordobae. A, dorsal sepal, 1; B, lateral sepals, 1; C, petals, 8; D, petal, viewed from side, 8; E, column, face view, 8; F, anther cap anterior, 15; G, anther cap posterior, 15; H, pair of pollinia, 15; J, labellum, 4; K, column, ovary and labellum, lateral view, 4; L, ovary transverse section, 10; Drawn from Kew Spirit Collection 72001, by Andrew Brown. The Board of Trustees of the Royal Botanic Gardens, Kew

6 Typical Dracula habitat, cloud forest in Ecuador. Photo. Phillip Cribb. Typical Dracula habitat in Ecuador; a branch covered in Bromeliads and orchids, in this case Dracula andreetae (Lauer) Lauer. Photo. Phillip Cribb. 104 The Board of Trustees of the Royal Botanic Gardens, Kew 2007.

7 also increased, with the inevitable destruction of vast areas of forest. Orchids are currently under threat in the wild throughout the world, and Ecuador is no exception ( Dodson & Escobar, 1994 ). Very high levels of endemism are found in Dracula, 61.33% of species being known from a single site. Many of these are in demand by nurseries and amateur growers. Unscrupulous collecting for the horticultural trade has resulted in many species facing near extinction in the wild (Koopowitz, 1993 ). Dracula cordobae is among these threatened species and has been classified as Vulnerable (Vu A4d) by Valencia et al., (2000). Dracula cordobae was first discovered in 1979 by Calaway Dodson and Clever Cordoba, after whom it was named. Dodson writes I was on a collecting trip with the late Dr. Al Gentry and Roberto Estrada of Guayaquil to the very wet tropical montane forest about 12 km west of Pinas in southwestern Ecuador in Roberto had an excellent orchid collecting assistant named Clever Cordoba who had climbed down the extremely steep roadside in search of orchids. He came back carrying a flowering plant of what was later described as Dracula cordobae Luer. It was spectacular and showed promise of being an excellent parent in crosses that would provide warmer temperature tolerance. The elevation of the site was 800 m and therefore rather low for larger flowered Draculas. The plants grew on the trunks of large trees in very wet cloud forest. Also growing on the roadside embankment were flowering plants of Sievekingia reichenbachiana, Polycycnis morganii, and Benzingia estradae among many other interesting orchids ( Dodson pers. com., 2003 ). C ULTIVATION. Dracula cordobae is grown at Kew in a cool greenhouse, with an ideal winter minimum temperature of 12ºC and maximum of 14ºC, and with constant moisture and humidity of 75 85%. It prefers a well-drained compost of pine bark mix, using medium and fine grades, charcoal and perlite. Dracula species send their flowers down through the compost, so they need to be grown in baskets and preferably repotted yearly. The plant figured here flowered in October 2003 at Kew and the flowers are preserved in the Kew Spirit Collection (72001). Dracula cordobae Luer, Selbyana 5: 146 (1979). Type : SW Ecuador, Prov. of El Oro, between Pinas & Santa Rosa, alt. 800 m. July 1979, Dodson, Morgan, Perry & Cordoba 8469, ( holotype SEL). The Board of Trustees of the Royal Botanic Gardens, Kew

8 D ESCRIPTION. Medium-sized to large epiphytic herb. Roots slender. Ramicauls densely caespitose, cm long, slender, erect, enclosed by 2 3 loose, tubular sheaths. Leaves cm long (including 2 4 cm long petiole), 2 4 cm wide, narrowly elliptical, gradually narrowed and conduplicate at the base, acute, carinate, thinly coriaceous, erect. Infl orescence a congested, successivelyflowered raceme; peduncle 8 19 cm long, slender horizontal to descending, with sparse bracts; floral bract 1 cm long, tubular. Flowers medium in size, sepals creamy-white, suffused and intensely spotted with red-brown on the margins, tails dark brown, petals white, marked brown, lip white, column white. Pedicel-with-ovary cm long, terete, minutely subverrucose. Dorsal sepal cm, long-pubescent within, ovate, acute, connate with lateral sepals for 0.6 cm to form a flat, widely spread flower, contracted into a slender, erect, 4 7 cm long tail. Lateral sepals cm, long-pubescent within, obliquely ovate, acute, connate for 1.2 cm to form a shallow mentum, contracted into slender tails similar to the dorsal sepal. Petals cm, oblong, cartilaginous, apex bivalvate, papillose between the laminae, inner lamina acute, outer rounded, recurved. Lip cm, spathulate; hypochile cm, oblong, with acute marginal angles, centrally cleft, with a concave base hinged to the column-foot; epichile cm, suborbicular-elliptical, concave, margins erect, denticulate, concavity ornamented with 3 irregular, branching, elevated nerves and numerous secondary nerves to either side ending in the marginal teeth. Column 0.45 cm long, semiterete; foot 0.3 cm long, stout. D ISTRIBUTION. Ecuador in the provinces of El Oro, Los Ríos, Pichincha and Zamora-Chinchipe. H ABITAT. Hill forest and lower montane cloud forest, embankments on rich, well drained humic soils; m. F LOWERING TIME. January to March, July and October. A CKNOWLEDGEMENTS. The author thanks Dave Roberts and Jeffrey Wood for their comments, and Paloma Malaxechevarria for comments on the cultivation of Dracula at Kew. REFERENCES Dodson, C.H. & P.M. ( 1980 ). Icones Plantarum Tropicarum 1, Pl. 53 ; The Marie Selby Botanical Gardens, Sarasota, FL. Dodson, C. ( 2003 ). Why are there so many Orchid species? Lankesteriana 7 : Dodson, C.H. Escobar, R. ( 1994 ). Native Ecuadorian orchids I. Hola Colina, Medellin. Ferrusi, M. (1997 ). The genus Draculav. The Pleurothallid Alliance News IX: 1. Hermans, J. & Hermans C. (1997 ). An Annotated Checklist on the Genus Dracula. Reprinted from the Orchid Digest 61(4), Oct., Nov., Dec. Jørgensen, P.M. & León-Yánez, S. ( 1999 ). Catalogue of the vascular plants of Ecuador. Missouri Botanical Garden Press, St. Louis. Kaiser, R. ( 1993 ). The scent of orchids: olfactory and chemical investigations. Elsevier, London. 106 The Board of Trustees of the Royal Botanic Gardens, Kew 2007.

9 Koopowitz, H. et al. (1993 ). Species distribution profiles of the neotropical orchids Masdevallia and Dracula (Pleurothallidinae, Orchidaceae); implications for conservation. Biodiversity and Conservation 2, Luer., C.A. (1993 ). Icones Pleurothallidinarum X: systematics of Dracula. Missouri Botanical Garden, Missouri. Luer, C. ( 1979 ). Icones Pleurothallidinarum (Orchidaceae): Miscellaneous new species in the Pleurothallidinae Selbyana 5 (2 ): Tremblay, R.L. et al. (2005 ). Variation in sexual reproduction in orchids and its evolutionary consequences: a spasmodic journey to diversification. Biological Journal of the Linnean Society 84 ( 1 ): Van der Cingel, N.A. ( 2001 ). Atlas of orchid pollination: America, Africa, Asia and Australia. A.A. Balkema, Rotterdam. Valencia, R. et al. (2000 ). Libro rojo de las plantas endemicas del Ecuador. Herbario QCA, Pontificia Universidad Catolica del Ecuador, Quito. Vogel, S. ( 1978 ). Pilzmückenblumen als Pilzmimeten I & II. Flora Bd 167 : & World Checklist of Monocotyledons (2006 ). The Board of Trustees of the Royal Botanic Gardens, Kew. ( accessed ; 10.00GMT ). TROPICOS ( 2006 ). The Board of Trustees of the Royal Botanic Gardens, Kew