TWO NEW TAXA OF MARCGRAVIASTRUM (MARCGRAVIACEAE) AND A CATALOGUE OF COLOMBIAN TAXA OF THIS GENUS1

A new species of Marcgraviastrum is validated, described, and illustrated. The new species is known only from the Colombian Guayana (Departments of Caquetá, Guaviare, and Vaupés). Its morphological relationships are discussed. Furthermore, a new combination into Marcgraviastrum is published. A checklist of the nine Colombian species of the genus is presented.

TWO NEW TAXA OF MARCGRAVIASTRUM(MARCGRAVIACEAE) AND A CATALOGUE OF COLOMBIAN TAXA OF THIS GENUS

Dos nuevos taxones de Marcgraviastrum(Marcgraviaceae) y catálogo de las especiescolombianas delgénero

DIEGO GIRALDO-CAÑAS 
STEFAN DRESSLER

Instituto de Ciencias Naturales, Universidad Nacional de Colombia, Apartado 7495, Bogotá, D. C., Colombia. dagiraldoc@unal.edu.co

Forschungsinstitut Senckenberg, Herbarium, Senckeberganlage 25, D-60325 Frankfurt/Main, Germany. Stefan.Dressler@senckenberg.de

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ABSTRACT

A new species of Marcgraviastrum is validated, described, and illustrated. The new species is known only from the Colombian Guayana (Departments of Caquetá, Guaviare, and Vaupés). Its morphological relationships are discussed. Furthermore, a new combination into Marcgraviastrum is published. A checklist of the nine Colombian species of the genus is presented.

Key words. Colombian Flora, Neotropical Flora, Marcgraviaceae, Marcgraviastrum, Norantea.

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RESUMEN

Se valida, describe e ilustra una nueva especie de Marcgraviastrum. La nueva especie sólo se conoce de la Guayana colombiana (departamentos de Caquetá, Guavire y Vaupés). Se discuten sus relaciones morfológicas. Adicionalmente, se publica una nueva combinación en el género Marcgraviastrum. Se incluye el catálogo de las nueve especies del género presentes en Colombia.

Palabras clave. Flora neotropical, Flora de Colombia, Marcgraviaceae, Marcgraviastrum, Norantea.

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Recibido:   17/02/2011 
Aceptado:  01/03/2012

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INTRODUCTION

When the U.S. American Hollis Gail Bedell presented her comprehensive thesis on the Norantea complex (Marcgraviaceae) in 1985, she unfortunately did not validate her new taxa therein (explicitly stated on page ii). The Dutch botanist Adrianus Cornelis de Roon had studied Marcgraviaceae earlier for his Ph.D. thesis (1975) but had agreed with Bedell to share authorship of his new findings in the complex genus Norantea and gave his notes for use in her work. She elevated the subgenera to generic rank and generated thourough descriptions of all species. Consequently, new taxa were assigned with the authorship de Roon & Bedell in her thesis but only one new combination, Schwartzia spiciflora (A. L. Juss.) Bedell, was validated by herself thereafter (Bedell 1989). All other names remained unpublished. Before validating some generic names in 1997 (de Roon & Dressler 1997) the authors had invited Bedell to take part in this publication with no success.

Over the years a considerable number of these names have been validated (Pool 1993, de Roon & Dressler 1997, 1999, Dressler 1999, Giraldo-Cañas 2002a, de Roon & Giraldo-Cañas 2006). Furthermore, a number of taxa in the genus Schwartzia have been published under different names [e.g. Schwartzia lozaniana Gir.-Cañas =Schwartzia venusta de Roon & Bedell (ined.), Schwartzia chocoensis Gir.-Cañas = Schwartzia foreroi de Roon & Bedell (ined.), Schwartzia antioquensis Gir.-Cañas = Schwartzia sclerophylla de Roon & Bedell (ined.),Schwartzia renvoizei Gir.-Cañas = Schwartzia micradenia de Roon & Bedell (ined.)] (Giraldo-Cañas 2001a, 2001b, 2002a, 2002b, 2003, 2004, 2005).

Two of de Roon & Bedell's names are still invalid. One species requires combination into the genusMarcgraviastrum and one new species needs to be properly described. Its name was already used in a publication (Cárdenas López et al. 2008: 84, 135 incl. photo). In order to end this unfortunate situation these taxonomic novelties are validated here.

Marcgraviastrum (Wittm. ex Szyszyl.) de Roon & S. Dressler is a small genus of the Neotropical family Marcgraviaceae comprising 15 species distributed in wet lowland forests or montane rain and cloud forests in Central (Nicaragua to Panama) and South America (Colombia, Venezuela, Guianas, Ecuador, Peru, Bolivia, and Brazil) (Dressler 2004a, Giraldo-Cañas 2011). The different species of Marcgraviastrum are sprawling epiphytic, hemi-epiphytic or terrestrial shrubs and lianas with sessile or petiolate leaves, and the venation is pinnate brochidodromous. The inflorescence in Marcgraviastrum is a terminal umbelliformly contracted raceme and this is erect when is in bud and flower, while when the fruits mature may become pendulous in some species. The number of flowers per inflorescence varies from 2-3 to 18-22, and this number is correlated with the size of the flowers; thus, species with large flowers have fewer flowers per inflorescence than those species with small flowers (Bedell 1985).

This genus is easily distinguished from Norantea Aubl. and other related genera of the subfamily Noranteoideae by its umbelliformly contracted raceme. This character is shared with Marcgravia L., the only genus of subfamily Marcgravioideae, but Marcgraviastrum differs from this genus in having 5-merous flowers (4-merous inMarcgravia), petals free or variously connate (completely connate into a calyptra in Marcgravia), and leaves spirally arranged (distichous in Marcgravia). Furthermore, in Marcgraviastrum like in the whole subfamily Noranteoideae each pedicel bears a nectary. This is in contrast to the situation in the genus Marcgravia where only the central flowers of the inflorescence, which remain sterile and vestigal, develop a nectary. For further characteristics and a key to the genera of the family see Bedell (1985), Dressler (2004a, 2004b, 2008), de Roon & Giraldo-Cañas (2006), and Giraldo-Cañas (2007, 2011).

MATERIALS AND METHODS

This study is based on the examination of herbarium specimens from A, AMES, AAU, B, BM, CAUP, CHOCO, COAH, COL, CR, CUVC, F, GH, HUA, JAUM, K, MA, MEDEL, MEXU, MO, MPU, NY, P, PMA, PSO, S, SI, U, US, VEN, W, and WU [abbreviations according to Holmgren et al. (1990)]. The morphological species concept is based on Crisci (1994) and Uribe Meléndez (2008). The description and the Latin diagnosis are based on Bedell (1985), with some changes made herein.

RESULTS AND DISCUSSION

Marcgraviastrum elegans de Roon & Bedell ex Gir.-Cañas & S. Dressler, sp. nov. TYPE: COLOMBIA. Vaupés. Mitú and vicinity; lower Río Kubiyú, savanna, 11 November 1976, J. L. Zarucchi 2210 (holotype: COL!; isotypes: AMES!, COAH!, MO [not seen, fide Tropicos], US!). Fig. 1.

Frutex. Folia elliptico-oblonga (3) 5.8- 13,5 cm longa et (1.4) 2.5- 3.5 (4) cm lata, basibus cordatis, apicibus acutis; glandes hypophyllae 2 vel 3, 3- 5 mm distantae ex marginibus folii. Axes inflorescentiarum 1- 2.5 cm longi; flores (8) 9-15; pedicelli 4- 7.5 cm longi et 2- 3 mm lati; nectaria sacciformia (1.5) 1.8- 2.7 cm longa et (5) 7- 9 mm lata, inserta 1.2- 1.7 cm ex basibus pedicellorum; stamina 42-48; ovarium 5-locullatum.

Robust and scandent shrubs 2- 3 m tall; branches ligneous and subterete with papery, yellowish-red bark on young branches, glabrous and red-brown on mature branches. Leaves sessile to subsessile (petiole up to 0.3 cm long), glaucous on both surfaces, dark green above and pale below, producing a long ciliate fracture when broken perpendicular to the midvein; lamina (3) 5.8- 13.5 cm long, (1.4) 2.5-3.5 (4) cm wide, elliptic-oblong, basally cordate, apically acute to obtuse through the loss of the mucro, with revolute margins and 2 or 3 smallhypophyllous glands per side 3- 5 mm from the margin and usually only visible with a hand lens; midvein obscure above, subprominent below, the lateral veins obscure on both surfaces or subprominent below.Inflorescence axis 1- 2.5 cm long with (8) 9-15 flowers on slender pedicels 4- 7.5 cm long, 2- 3 mm wide; foliaceous bracts 1- 3.5 cm long, 0.4- 1.4 cm wide, elliptic-oblong, with one pair of hypophyllous glands;nectariferous bracts (1.5) 1.8- 2.7 cm long, (5) 7- 9 mm wide, leathery and reddish-green, saccate, with a revolute or trumpet-shaped margin with an apiculate lip around the slightly constricted orifice, recurved and pendulous, sessile, and attached 1.2- 1.7 cm from the base of the pedicel, or, frequently, with the nectaries on the lower two or three pedicels not developing completely but remaining leaf-like and only slightly evaginated.Flowers leathery and greenish-white; buds (7) 9- 12 mm long; bracteoles 4- 6 mm long, (4) 5- 7 mm wide, suborbicular, appressed to the calyx; sepals (4) 5- 7 mm long, (5) 6- 8 mm wide, orbicular to suborbicular;petals (8) 9- 14 mm long, (5) 7- 8 mm wide, free, oblong; stamens 42-48, 9- 12 mm long; filaments free, linear; anthers sagittate with yellow pollen; ovary 6-8 (9) mm tall, pyriform, 5-locular with 16-20 ovules per locule;style 3- 4 mm long, cylindrical; stigma capitate and somewhat 5-radiate. Fruit 1.1- 1.8 cm in diameter, red or bright orange, with persistent styles; seeds 2.5- 4 mm long, 12-16 per locule, reniform, shiny reddish-black.

Etymology. Elegans, elegant, fine, referring to the graceful appearance of this species.

Distribution and habitat. Marcgraviastrum elegans has only been collected from quartzite or granitic soils ("lajas", inselbergs) along the edges of forest or savannas in Caquetá, Guaviare, and Vaupés (Colombian Guayana) (Fig. 2).

Remarks. This species is recognized by its robust habit and unusual leaves that are narrow, elliptic-oblong and basally cordate. It is probably most closely related to Marcgraviastrum mixtum (Triana & Planch.) Bedell, from which it is readily distinguished by features given in Table 1.

Paratypes. COLOMBIA. Caquetá: Municipio de Solano, Solano, Estación Puerto Abeja, sector sur-oriental del parque nacional natural Chiribiquete, 19 Nov 1999, A. M. Eusse 830 (COAH). Guaviare: San José del Guaviare; río Guaviare, sabana y cerros graníticos, ca. 270 m, 12 Nov 1939, J. Cuatrecasas 7685 (COL, US). Mesa La Lindosa, cerrito a 15- 20 km al sur de San José del Guaviare, 400- 600 m, 13-15 Dec 1950, J. M. Idrobo & R. E. Schultes 623 (COL, GH, U, US). Municipio de San José del Guaviare, a 20 minutos del casco urbano, en el sitio turístico Los Pozoz Naturales, aguas arriba, en la antigua represa, afloramientos rocosos en sabanas degradadas, 262 m, 27 Mar 1997, R. López & O. J. Rodríguez 2413 (COAH, COL). Serranía La Lindosa, quebrada Los Pozoz, Feb 2000, J. Pinzón 95 ( COL). San José del Guaviare, antigua represa, sobre roca de arenisca, 200- 250 m, 27 Dec 1993, C. Sastre et al. 9195 (COL, P [not seen]). Municipio de San José del Guaviare, serranía de La Lindosa, afloramiento rocoso, quedraga Agua Bonita entre charco La Lindosa hasta La Reserva, 19 Mar 2008, D Cárdenas et al. 21335(COAH). Vaupés: Savanna de Yapobodá; near Maloca de Yararaca, Alto Río Cuduyarí, 10 Dec 1943, P. H. Allen 3227 ( COL, MO [not seen], US [not seen]). Municipio de Mitú, sabana de Yapobodá, entre la entrada a la sabana desde el cerro Umukû hasta las cuevas de Umukû, 500- 520 m, 19 Mar 2003, J. Betancur et al. 9971 ( COAH, COL). Río Kuduyarí, sabana con arenisca de Yapobodá, ca. 350- 400 m, 25 Jun 1958, H. García Barriga et al. 16015 ( COL, GH). Caño Cubiyú, comunidad indígena La Sabana, 200 m, 26 Apr 1993, S. Madriñán et al. 1171 ( COL). Municipio de Mitú, río Vaupés, comunidad de Mandi, Oct 1993, A. Mejía et al. 2713 ( COAH, COL). Río Kuduyarí (tributary of Río Vaupés), Yapobodá, quartzite savannah near head waters, ca. 300 m, Apr 1953, R. E. Schultes & I. Cabrera 19986 (U, US). Mitú and vicinity; along lower Río Kubiyú, sandstone savanna, 31 Mar 1975,J. L. Zarucchi et al. 1131 ( AMES, COL); 25 Sep 1975, J. L. Zarucchi 2141 ( AMES, COAH, COL, INPA [not seen]).

A new combination in Marcgraviastrum

Marcgraviastrum obovatum (G. Don) Bedell ex Gir.-Cañas & S. Dressler, comb. nov. [in Bedell, H.G., 1985: A generic revision of Marcgraviaceae I, The Norantea complex. Ph.D. Diss. (ined.), Univ. Maryland, College Park, MD., p. 370.] = Norantea obovata G. Don, Gen. Syst. 1: 625. 1831. TYPE: Iconotype Ruiz & Pavón, Fl. Peruv. 5: pl. 436 (ined., publ. in E. A. López, Anales Inst. Bot. Cavanilles 16: 393, pl. 436 [p. 443]. 1958). EPITYPE (hic designatus): Peru "in silvis Pillao ad Chacahuassi" [Ruiz & Pavón apud E. A. López 1958: 394], Ruiz & Pavón s.n., a. 1787 (Epi: MA, Iso: Bdestr. [F-neg. no. 9707], F-842882, F-843295 [fragm. ex MA], MA; possibly same collection: G [F-neg. no. 23876], GFW, HAL [0021195]).

Catalogue of the genus Marcgraviastrum for Colombia

Marcgraviastrum (Wittm. ex Szyszyl.) de Roon & S. Dressler: Nine species in Colombia (two endemic species). 
Marcgraviastrum apaporensis de Roon & Bedell 
Ref.: R. E. Schultes 14589 ( COL, GH, US ). 
Region: Amazonia, Guayana (0- 500 m) 
Departments: Amazonas, Vaupés. 
Endemic

Marcgraviastrum elegans de Roon & Bedell ex Gir.-Cañas & S. Dressler

Ref.: J. L. Zarucchi 2210 (COL, US). 
Region: Guayana (0- 500 m) 
Departments: Caquetá, Guaviare, Vaupés. 
Endemic

Marcgraviastrum gigantophyllum (Gilg) Bedell ex S. Dressler

Sin.: Norantea gigantophylla Gilg 
Ref.: J. L. Luteyn 10672 ( JAUM, NY). 
Region: Biogeographic Chocó (0- 1500 m) 
Departments: Antioquia, Chocó. 
Native

Marcgraviastrum macrocarpum (G. Don) Bedell ex S. Dressler

Sin.: Norantea eoetvoesorum V. A. Richt., Norantea macrocarpa G. Don, Norantea pardoana Weberb. & Gilg 
Ref.: D. Giraldo-Cañas 5026 (COL). 
Region: Andes (1500- 3000 m) 
Departments: Cundinamarca, Boyacá, Nariño, Santander. 
Native

Marcgraviastrum mixtum (Triana & Planch.) Bedell

Sin.: Norantea curva J. F. Macbr., Norantea mixta Triana & Planch., Norantea peduncularis Poepp. ex Wittm.,Norantea uleana Pilg. 
Ref.: D. Giraldo-Cañas 3306 (COL). 
Region: Amazonia, Andes, Biogeographic Chocó, Cauca Valley, Guayana, Magdalena Valley, Orinoquia (0- 2000 m) 
Departments: Amazonas, Antioquia, Boyacá, Caquetá, Cauca, Chocó, Cundinamarca, Huila, Meta, Nariño, Putumayo, Quindío, Santander, Tolima, Valle del Cauca, Vaupés. 
Native

Marcgraviastrum pauciflorumde Roon & Bedell

Ref.: A. Gentry 40737 ( COL, MO). 
Region: Andes, Biogeographic Chocó (0- 1000 m) 
Departments: Chocó, Valle del Cauca. 
Native

Marcgraviastrum sodiroi (Gilg) Bedell ex S. Dressler

Sin.: Norantea sodiroi Gilg 
Ref.: D. Giraldo-Cañas 1937-a ( COL). 
Region: Andes (500- 2500 m) 
Departments: Antioquia, Cauca, Nariño, Santander. 
Native

Marcgraviastrum subsessile (Benth.) Bedell

Sin.: Norantea subsessilis (Benth.) Donn. Sm., Ruyschia subsessilis Benth. 
Ref.: E. P. Killip 33217 ( COL, MA, NY, US)). 
Region: Andes, Biogeographic Chocó (0- 1000 m) 
Departments: Antioquia, Cauca, Chocó, Nariño, Valle del Cauca. 
Native

Marcgraviastrum vogelii de Roon & Bedell

Ref.: L. E. Mora 4148 ( COL). 
Region: Andes, Biogeographic Chocó (500- 2000 m) 
Departments: Chocó, Nariño, Santander, Valle del Cauca. 
Native

ACKNOWLEDGEMENTS

We thank Ad de Roon (formerly U) and Paul M. Peterson (US) for valuable help. The curators and staff members of the following herbaria are acknowledged for putting herbarium specimens at our disposal: A, AMES, AAU, B, BM, CAUP, CHOCO, COAH, COL, CR, CUVC, F, HUA, IBGE, JAUM, K, MA, MEDEL, MEXU, MO, MPU, NY, P, PMA, PSO, RSA, S, SI, SP, U, UIS, US, VEN, W, and WU. Visits by D. Giraldo-Cañas to US, MO, and RSA were financed by the Universidad Nacional de Colombia ( Bogotá D.C.), Smithsonian Institution ( Washington D.C., USA ), Missouri Botanical Garden ( St. Louis, Missouri, USA ), and Rancho Santa Ana Botanic Garden ( Claremont, California, USA ). Visits of S. Dressler to COL, COAH, HUA, JAUM, MEDEL were supported by the Andrew W. Mellon Foundation, New York and to A, AMES & GH by the Dr. Senckenbergische Stiftung Frankfurt/M. We thank two anonymous reviewers for their critique of the manuscript. The illustration was elaborated by Marcela Morales (COL). This paper is derived from the project "Estudios sistemáticos en el complejo Norantea Aubl. (Marcgraviaceae)", of the "División de Investigación (DIB) de la Universidad Nacional de Colombia", Bogotá D.C.

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LITERATURE CITED

1. BEDELL, H. G. 1985. A generic revision of Marcgraviaceae, I. The Norantea complex. Ph.D. Dissertation, University of Maryland, College Park.

2. BEDELL, H. G. 1989. Marcgraviaceae. In: R. A. Howard, Flora of the Lesser Antilles 5: 300-310.

3. CÁRDENAS LÓPEZ, D., N. CASTAÑO ARBOLEDA, M. ZUBIETA VEGA & M. JARAMILLO ECHEVERRY. 2008. Flora de las formaciones rocosas de la serranía de La Lindosa. Instituto Amazónico de Investigaciones Científicas Sinchi, Bogotá D. C.

4. CRISCI, J. 1994. La especie: realidad y conceptos: 53-64. In: J. Llorente Bousquets & I. Luna (compiladores), Taxonomía biológica. Universidad Autónoma de México-Fondo de Cultura Económica, México D. F.

5. DE ROON, A. C. 1975. Contributions towards a monograph of the Marcgraviaceae. Thesis, University of Utrecht, Utrecht.

6. DE ROON, A. C. & S. DRESSLER. 1997. New taxa of Norantea Aubl. s.l. (Marcgraviaceae) from Central America and adjacent South America. Bot. Jahrb. Syst. 119: 327-335.

7. DE ROON, A. C. & S. DRESSLER. 1999. New taxa of Sarcopera and Marcgraviastrum (Marcgraviaceae) from the Guayana Shield. Novon 9: 248-252.

8. DE ROON, A. C. & D. GIRALDO-CAÑAS. 2006. Contributions toward a monograph of Norantea complex (Marcgraviaceae, Ericales): Validation of four new species for Marcgraviastrum. Caldasia 28 (1): 15-22.

9. DRESSLER, S. 1999. Marcgraviaceae. In: P. M. Jørgensen & S. León-Yánez (eds.), Catálogo de las plantas vasculares del Ecuador. Monogr. Syst. Bot. Missouri Bot. Gard. 75: 559-560, 955-956.

10. DRESSLER, S. 2004a. Marcgraviaceae. In: K. Kubitzki (ed.), The Families and Genera of Vascular Plants 6: 258-265. Springer, Berlin.

11. DRESSLER, S. 2004b. Marcgraviaceae. In: N. Smith, S. A. Mori, A. Henderson, D. W. Stevenson & S. V. Heald (eds.), Flowering Plants of the Neotropics: 236-238. Princeton University Press, Princeton & Oxford.

12. DRESSLER, S. 2008. Marcgraviaceae. In: W. Milliken, B. Klitgaard, A. Baracat & N. Hind (eds), Neotropikey - Interactive key and information resources for flowering plants of the Neotropics. www.kew.org/neotropikey(accessed 16 May 2011).

13. GIRALDO-CAÑAS, D. 2001a. Dos nuevas especies de Schwartzia (Marcgraviaceae) de Colombia. Revista Acad. Colomb. Ci. Exact. 25 (97): 477-482.

14. GIRALDO-CAÑAS, D. 2001b. Una nueva especie de Schwartzia (Marcgraviaceae) de la vertiente occidental andina de Colombia y Ecuador. Caldasia 23 (2): 383-388.

15. GIRALDO-CAÑAS, D. 2002a. Novedades taxonómicas y corológicas en Marcgraviastrum, Sarcopera y Schwartzia (Marcgraviaceae) de Sudamérica. Hickenia 3 (32): 119-123.

16. GIRALDO-CAÑAS, D. 2002b. Estudios en el género Schwartzia Vellozo (Marcgraviaceae): una nueva especie de la Cordillera Central andina de Colombia. Novon 12 (4): 456-459.

17. GIRALDO-CAÑAS, D. 2003. Revisión de las especies colombianas del género Schwartzia (Marcgraviaceae). Caldasia 25 (1): 1-21.

18. GIRALDO-CAÑAS, D. 2004. Una nueva especie de Schwartzia (Complejo Norantea, Marcgraviaceae) de la región andina de Colombia. Caldasia 26 (2): 423-428.

19. GIRALDO-CAÑAS, D. 2005. Validation of a new species of Schwartzia (Marcgraviaceae) and synopsis of the genus for Ecuador. Novon 15 (1): 123-127.

20. GIRALDO-CAÑAS, D. 2007. Un nuevo género de la familia neotropical Marcgraviaceae (Ericales) y circunscripción del Complejo Norantea. Caldasia 29 (2): 203-217.

21. GIRALDO-CAÑAS, D. 2011. Estudios morfológicos y taxonómicos en el complejo Norantea (Marcgraviaceae): Revisión de Norantea, Pseudosarcopera y Schwartzia. Biblioteca José Jerónimo Triana 22: 1-176. Instituto de Ciencias Naturales, Universidad Nacional de Colombia, Bogotá D. C.

22. HOLMGREN, P., N. HOLMGREN & L. BARNETT. 1990. Index Herbariorum. Part I: The Herbaria of the World. The New York Botanical Garden, New York.

23. POOL, A. 1993. Marcgraviaceae. In: L. Brako & J. Zarucchi (eds.), Catálogo de las angiospermas y gimnospermas del Perú. Monogr. Syst. Bot. Missouri Bot. Gard. 45: 670-672 and 1256.

24. URIBE MELÉNDEZ, J. 2008. Monografía de Frullania subgénero Meteoriopsis (Frullaniaceae, Marchantiophyta). Caldasia 30 (1): 49-94.