Of the New York Botanical Garden Volume 36
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Memoirs Of The New York Botanical Garden Volume 36 The Systematics of Montanoa (Asteraceae, Heliantheae) V. A. Funk Issued 26 November 1982 MEMOIRS OF THE NEW YORK BOTANICAL GARDEN ADVISORY BOARD GHILLEAN T. PRANCE, Vice-President WILLIAM C. STEERE, President of Botanical Research Emeritus and Senior Scientist The New York Botanical Garden The New York Botanical Garden BASSETT MAGUIRE, Senior Scientist ARTHUR CRONQUIST, Senior Scientist The New York Botanical Garden The New York Botanical Garden NOEL H. HOLMGREN, Chairman, Publications Committee and Curator The New York Botanical Garden EDITORIAL BOARD CLARK T. ROGERSON, Editor The New York Botanical Garden Bronx, New York 10458 WILLIAM R. BUCK, Associate Editor The New York Botanical Garden Bronx, New York 10458 SHERWTN CARLQUIST ROGERS MCVAUGH, Curator Rancho Santa Ana Botanic Garden University of Michigan PETER H. RAVEN, Director JOHN WURDACK, Curator Missouri Botanical Garden Smithsonian Institution The MEMOIRS are published at irregular intervals in issues and volumes of various sizes and are designed to include results of original botanical research by members of the Garden's staff, or by botanists who have collaborated in one or more of the Garden's research programs. Ordinarily only manuscripts of fifty or more typewritten pages will be considered for publication. Manuscripts should be submitted to the Editor. For further information re- garding editorial policy and instructions for the preparation of manuscripts, ad- dress the Editor. Orders for past and forthcoming issues and volumes should be placed with: Publications Office The New York Botanical Garden Bronx, New York 10458 THE SYSTEMATICS OF MONTANOA (ASTERACEAE, HELIANTHEAE) V. A. Funk CONTENTS Summary I Introduction 1 Taxonomic history 2 Synopsis of the taxonomy 4 Generic affinities 4 Morphology and taxonomic characters 7 Leaf morphology 14 Cytology 18 Cladistic analysis 21 Taxonomic treatment 31 Key to the species 32 Subgenus Montanoa 34 Subgenus Acanlhocarphae 67 Doubtful and excluded species 123 Acknowledgments _____1_1____„III_______ „„________!_1_____ .^_ !__J_J ;_: L___ 124 Literature cited 124 Collector abbreviations 126 Index 132 MEMOIRS of THE NEW YORK BOTANICAL GARDEN Volume 36 The New York Botanical Garden Bronx, New York 10458 ISSUED 26 November 1982 Library of Congress Cataloging in Publication Data Funk, V. A. (Vicki A.), 1947- The Systematics of Montanoa (Asteraceae, Heliantheae) (Memoirs of the New York Botanical Garden; v. 36) Based on the author's thesis (Ph.D.—Ohio State University, 1980) Bibliography: p. Includes index. 1. Montanoa—Classification. 2. Botany—Latin America- Classification. I. Title. II. Series. QK1.N525. vol. 36 [QK495.C74] 581s 82-7878 ISBN 0-89327-243-4 [583'.55] AACR2 Copyright © 1982 The New York Botanical Garden All material subject to this copyright appearing in the Memoirs of The New York Botanical Garden may be photocopied for the purpose of scientific or educational advancement. International Standard Book Number 0-89327-243-4 NOVEMBER 1982 MEMOIRS OF THE NEW YORK BOTANICAL GARDEN 36:1-133 THE SYSTEMATICS OF MONTANOA (ASTERACEAE, HELIANTHEAE)1 V. A. FUNK2 SUMMARY Montanoa Cerv. (Asteraceae, Heliantheae) includes woody, white-rayed composites with Latin American distributions. Species recognition has always been difficult in the genus because of variation in such features as leaf shape, size and number of involucral bracts and head size. This variation was studied on the individual, inter- and infra-populational levels. Data collected from extensive field and herbarium studies were combined with the results of greenhouse experiments to determine the use- fulness of such characters for species determination. Characters with high levels of consistency were used to delimit 25 species (30 taxa) within the genus. These taxa are divided into two subgenera, Montanoa and Acanthocarphae DC. Chromosome counts for 21 of the taxa are presented and re- vealed three high level polyploids that are all high altitude trees. A cladistic analysis showed extensive parallel evolution in a number of the more conspicuous characters. Basing the hierarchy of Montanoa on the branching pattern produced from the cladistic analysis has resulted in a more natural and predictive classification. Twenty-two of the species recognized are from the over 100 previously described species. There are three new species described here, M. standleyi, M. josei and M. imbri- cata. Subgenus Montanoa is divided into two sections Montanoa and Echinocephalae sect, nov., with the latter having three series, Frutescentes ser. nov., Amoenae ser. nov. and Apertae ser. nov. Sub- genus Acanthocarphae has five series, all described here: Ovalifoliae, Quadrangulares, Hibiscifoliae, Intermediae and Grandiflorae. [Montanoa, Asteraceae, cytology, morphological variation, cladistics] INTRODUCTION Montanoa Cerv. in Llave & Lex. is a genus of attractive, woody Asteraceae, appropriately referred to as the "Daisy Trees" because of their white rays and yellow disc florets. Most members of this genus are shrubs, but a few are truly arborescent, and when in flower they present a spectacular display. The genus is widespread in Latin America and several species are cultivated in the warmer parts of the world. Montanoa is a well-defined genus occupying an isolated position within the tribe Heliantheae. Although definition of generic boundaries has never been a serious problem, the taxonomy within the genus has long plagued synantherol- ogists. The only revision of Montanoa was by Robinson and Greenman in 1899. While adequate for the time, this study was based entirely on herbarium material 1 Based on a dissertation submitted in partial fulfillment of the requirements for the degree of Doctor of Philosophy, Ohio State University, Columbus, Ohio, 1980. 2 Curator, Department of Botany, Smithsonian Institution, Washington, 0.C. 20560. Formerly Museum Intern, The New York Botanical Garden, Bronx, New York 10458. 2 MEMOIRS OF THE NEW YORK BOTANICAL GARDEN [VOL. 36 and therefore could not effectively deal with the two major problems in the genus: extensive morphological variation and widespread parallel evolution. The most extensive variation occurs in the leaves, but the involucral bracts, pubescence, disc florets and achenes also vary widely. In the present treatment the problem of morphological variation was ap- proached from three directions. First, variation on the individual and populational levels was examined during nine months of field studies in Latin America. Sec- ond, over 6000 herbarium sheets were examined in the laboratory to determine broad patterns of variation throughout the range of the taxa. Based on these field and laboratory observations, hypotheses were generated concerning the extent and causes of the variation. Third, whenever possible, these hypotheses were tested in greenhouse studies. These data were combined with information from cytological studies and correlated with patterns of geographical distribution; the result has been an improved understanding of the taxa. Once the morphological variation in Montanoa had been documented and the taxa circumscribed, an evolutionary branching pattern was constructed, using the method of Hennig (1950, 1966), to help understand the phylogeny of the genus. The resulting branching diagram (cladogram) was used to identify the characters that had probably undergone parallel evolution. An understanding of the morphological variation and an interpretation of par- allel evolution in Montanoa has resulted in a classification in the present treat- ment that is believed to be both informative and predictive. Also, the methods that have been used in studying the patterns of morphological variation in Mon- tanoa may be useful to other workers in dealing with variable genera in other parts of the Asteraceae as well as in other families. TAXONOMIC HISTORY Montanoa was first described by Kunth in Humboldt, Bonpland and Kunth (1820) as Eriocoma with the single species E. floribunda. This name, however, was a later homonym and therefore illegitimate because Nuttall in 1818 had used the same name for a genus of the Poaceae. The first valid description of Montanoa was by Cervantes in La Llave and Lexarza (1825), named for Dr. Luis Montana, a physician and naturalist from Puebla, Mexico (Blake, 1926a). One species, M. tomentosa, collected from the riverbanks near Mexico City, was included in the genus. Several other generic names have been applied to Montanoa. Cassini (1829 [reprint 1975]) used Eriocarpha, perhaps because he was aware that Eriocoma was a later homonym but not aware of the work of Cervantes. De Candolle (1836) changed the spelling of Montanoa to Montagnaea to more closely approximate the Spanish pronunciation of Dr. Montana's name (Koch, 1864). In his treatment he recognized eight species in two subgenera: Eriocarphae (distinguished by five ligules and hirsute pales) with two species; and Acanthocarphae (10 ligules and sparingly hirsute pales mucronate at the apex) with six species. All of the species in the second subgenus were new. De Candolle also listed in synonymy Priest- ley a, a Sesse and Mocino name for an unpublished plate of the Flora Mexicona. Two species were listed: P. longifolia (=Montanoa grandiflora) and P. squarrosa (=M. frutescens). A final monotypic genus, Uhdea, was published by Kunth (1847) as a taxon closely related to Montanoa but having larger flowering heads. It was named after the Prussian consul, Uhde, who sent seeds from Mexico to Paris where the