IS MANDEVILLA (APOCYNACEAE, MESECHITEAE) MONOPHYLETIC? EVIDENCE FROM FIVE PLASTID DNA LOCI AND MORPHOLOGY Author(s): André O. Simões , Mary E. Endress , Timotheüs van der Niet , Luiza S. Kinoshita , and Elena Conti Source: Annals of the Missouri Botanical Garden, 93(4):565-591. 2006. Published By: Missouri Botanical Garden DOI: http://dx.doi.org/10.3417/0026-6493(2006)93[565:IMAMME]2.0.CO;2 URL: http://www.bioone.org/doi/ full/10.3417/0026-6493%282006%2993%5B565%3AIMAMME%5D2.0.CO%3B2 BioOne (www.bioone.org) is a nonprofit, online aggregation of core research in the biological, ecological, and environmental sciences. BioOne provides a sustainable online platform for over 170 journals and books published by nonprofit societies, associations, museums, institutions, and presses. Your use of this PDF, the BioOne Web site, and all posted and associated content indicates your acceptance of BioOne’s Terms of Use, available at www.bioone.org/page/terms_of_use. Usage of BioOne content is strictly limited to personal, educational, and non-commercial use. Commercial inquiries or rights and permissions requests should be directed to the individual publisher as copyright holder. BioOne sees sustainable scholarly publishing as an inherently collaborative enterprise connecting authors, nonprofit publishers, academic institutions, research libraries, and research funders in the common goal of maximizing access to critical research. IS MANDEVILLA (APOCYNACEAE, Andre´ O. Simo˜es,2 Mary E. Endress,3 MESECHITEAE) Timotheu¨s van der Niet,3 Luiza S. Kinoshita,4 and Elena Conti3 MONOPHYLETIC? EVIDENCE FROM FIVE PLASTID DNA LOCI AND MORPHOLOGY1 ABSTRACT In order to test the monophyly of Mandevilla Lindl., the largest genus in tribe Mesechiteae (Apocynaceae, Apocynoideae), and its affinities to other genera in the tribe, maximum parsimony analysis was conducted on a data set comprising DNA sequences from five plastid loci (rpl16, rps16, and trnK introns; trnSGCU-trnGUUC intergenic spacer; and matK gene), as well as morphological data for 65 taxa of Mesechiteae (48, Mandevilla) and nine taxa from other tribes of the subfamily. Mandevilla,as circumscribed by Pichon, was found to be monophyletic, whereas Woodson’s circumscription proved to be polyphyletic. Thus defined, Mandevilla forms a strongly supported clade that can be divided into six clades of species groups. Most of the infrageneric taxa of Mandevilla proposed by Woodson and Pichon are polyphyletic. Many of the diagnostic characters previously used to define taxonomic groups are shown to have arisen multiple times, rendering them unsuitable for classificatory purposes. The similar growth form and tubular flowers of Macrosiphonia Mu¨ll. Arg. and Telosiphonia (Woodson) Henr., two geographically disjunct segregates, represent the most extreme case of parallel evolution within Mandevilla, with their striking similarities most likely correlated to colonization of open, dry habitats and pollination by hawkmoths. Key words: Apocynaceae, Mandevilla, matK, Mesechiteae, morphology, phylogenetic systematics, rpl16, rps16, trnK, trnSGCU-trnGUUC. Mandevilla Lindl., a member of tribe Mesechiteae, flowers up to 9 cm long. The genus is traditionally is the largest Neotropical genus in Apocynaceae and characterized by the following set of traits: racemose comprises about 150 species (Simo˜es et al., 2004; inflorescence; leaf blade with one to many colleters on Sales et al., 2006). It is distributed throughout the the adaxial surface, sometimes extending along the Neotropics, from Mexico to Argentina, in a wide midrib; and style head with five strongly protruding, variety of habitats such as deserts, savannas, tepuis, well-developed longitudinal ribs (Woodson, 1933; open grasslands, and forests. Morphological variation Pichon, 1948; Henrickson, 1996; Morales, 1998; is remarkable in the genus in both vegetative and Simo˜es & Kinoshita, 2002; Simo˜es et al., 2004). reproductive parts. Most species are vines, but erect A combination of high morphological diversity and shrubs are also common, while unbranched subshrubs broad geographic distribution makes Mandevilla one and epiphytes occur less frequently. Flower size and of the most challenging and complex genera of structure are also very diverse, ranging from in- Neotropical Apocynaceae, a fact that is reflected in conspicuous white, tubular flowers less than 1 cm its taxonomic history. The currently accepted circum- long to brightly colored, showy infundibuliform scription of Mandevilla was defined by Woodson in 1 The authors thank the following persons for providing plant material: Leonardo Alvarado Cardenas, Alberto Burquez, Mark Fishbein, Andre´ia Silva Flores, Paul Forster, Leonardo Galetto, Gu¨nter Gerlach, Sueli Maria Gomes, Phil Jenkins, Stephanie Lieberherr, Sigrid Liede, Ulrich Meve, Alicia Marticorena, Stefan Matezki, Francisco Morales, Emerson Pansarin, Siwert Nilsson, Marie Francoise Pre´vost, Ana Lilia Reina, Rodrigo Schu¨tz Rodrigues, Ju¨rg Scho¨nenberger, Tom Van Devender, Steve Yanoviak and Scott Zona; without their generosity, this study would not have been possible. We are especially grateful to Tom Wendt and Lindsay Woodruff of the Plant Resources Center at the University of Texas at Austin, for allowing us to remove leaf tissue from one of the only three known collections of Tintinnabularia mortonii. This study was partly supported by grants to A. Simo˜es from CAPES (Coordenac¸a˜o e Aperfeic¸oamento de Pessoal de Nı´vel Superior), FAPESP (Fundac¸a˜o de Amparo a` Pesquisa do Estado de Sa˜o Paulo) (00/04994-0), and the ‘‘Stipendien fu¨r Doktoriende aus Entwicklungsla¨ndern’’ from the Ressort Internationale Beziehungen and the Unifraustellen of the University of Zu¨rich, Switzerland. 2 Programa de Po´s-graduac¸a˜o em Biologia Vegetal, Instituto de Biologia, Universidade Estadual de Campinas, Caixa Postal 6109, Cep 13083-970, Campinas, Sa˜o Paulo, Brazil. Current address: Institute of Systematic Botany, University of Zurich, Zollikerstrasse 107, 8008 Zu¨rich, Switzerland. [email protected], [email protected] 3 Institute of Systematic Botany, University of Zurich, Zollikerstrasse 107, 8008 Zu¨rich, Switzerland. mendress@systbot. unizh.ch; [email protected]; [email protected] 4 Departamento de Botaˆnica, Instituto de Biologia, Universidade Estadual de Campinas, Caixa Postal 6109, Cep 13083-970, Campinas, Sa˜o Paulo, Brazil. [email protected] ANN.MISSOURI BOT.GARD. 93: 565–591. PUBLISHED ON 15 DECEMBER 2006. 566 Annals of the Missouri Botanical Garden 1933. In a broad taxonomic study of the Neotropical five and eight species, respectively, and are distrib- species of subfamily Apocynoideae, he made signif- uted in Mexico and Mesoamerica. Both of these icant changes in the circumscription of Mandevilla, sections were characterized by flowers with salverform including in its synonymy such genera as Exothoste- to tubular-salverform corollas, anthers with auriculate mon (G. Don) Woodson, Dipladenia A. DC., Laseguea bases, and five nectaries surrounding the ovary, but A. DC., Amblyanthera Mu¨ll. Arg., Heterothrix Mu¨ll. differed from one another in the size of the nectaries, Arg., and part of Echites P. Browne. Macrosiphonia which were said to be equal to or taller than the ovary Mu¨ll. Arg., a small group of shrubby species with long, in section Tubiflorae and shorter than the ovary in white, tubular flowers and a disjunct distribution in section Torosae. the arid zones of the southwestern U.S.A. and Mexico A revised classification of Mandevilla was pub- and the savannas of southern South America, was lished by Pichon in 1948. He expanded Woodson’s maintained by Woodson as a separate genus. He (1933) circumscription by including Macrosiphonia, admitted, however, that the distinctions between which he justified by arguing that the characters used Macrosiphonia and Mandevilla, based on plant habit, by Woodson to differentiate between the two genera flowering time, and style head structure, were were inconsistent and arbitrary. He did not consider extremely tenuous. He also cautiously recognized Woodson’s subgenera Macrosiphonia and Telosiphonia two subgenera in Macrosiphonia (Woodson, 1933: to be each other’s closest relatives, however, and 778), Telosiphonia Woodson and Eumacrosiphonia placed them in two distinct sections, based on the Woodson (5 Macrosiphonia), comprising the species absence of a pedicel, longer staminal filaments, and that occur in the Northern and Southern Hemispheres, larger pollen grains of the former. Within Mandevilla, respectively. Pichon recognized Woodson’s subgenus Mandevilla In addition to broadening the limits of Mandevilla, and subgenus Exothostemon as valid groups but did Woodson (1933) also proposed a morphologically not recognize his five sections within subgenus based infrageneric classification of the genus, with the Mandevilla. According to Pichon, the characters subgenera Exothostemon and Eumandevilla Woodson supporting these two subgenera were reliable, whereas (5 Mandevilla). The two subgenera were differentiat- those supporting the sections were highly inconsis- ed based on the following suite of morphological tent, with no real diagnostic states to define them. characters: species of subgenus Exothostemon have Pichon (1948) proposed a new infrageneric classifi- leaf colleters distributed along the entire length of the cation within Mandevilla, recognizing four sections midrib, calycine colleters with an opposite arrange- (Orthocaulon Pichon, Exothostemon Pichon, Megasi- ment,