Taxonomic keys to the species listed in Rio Mayo plants Item Type text; Thesis-Reproduction (electronic) Authors Soares, José de Ribamar Pinto, 1940- Publisher The University of Arizona. Rights Copyright © is held by the author. Digital access to this material is made possible by the University Libraries, University of Arizona. Further transmission, reproduction or presentation (such as public display or performance) of protected items is prohibited except with permission of the author. Download date 24/09/2021 05:59:07 Link to Item http://hdl.handle.net/10150/554577 TAXONOMIC KEYS TO THE SPECIES LISTED IN RIO MAYO PLANTS by Jose de Ribamar Pinto Soares A Thesis Submitted to the Faculty of the DEPARTMENT OF BIOLOGICAL SCIENCES In Partial Fulfillment of the Requirements For the Degree of MASTER OF SCIENCE WITH A MAJOR IN BOTANY In the Graduate College THE UNIVERSITY OF ARIZONA 1 9 7 3 STATEMENT 'EY AUTHOR This thesis has been submitted in partial fulfillment of re­ quirements for an advanced degree at The University of Arizona and is deposited in the University Library to be made available to borrowers under rules of the Library. Brief quotations from this thesis are allowable without special permission, provided that accurate acknowledgment of source is made. Requests for permission for extended quotation from or reproduction of this manuscript in whole or in part may be granted by the head of the major department or the Dean of the Graduate College when in his judg­ ment the proposed use of the material is in the interests of scholar­ ship. In all other instances, however, permission must be obtained from the author. SIGNED APPROVAL BY THESIS DIRECTOR This thesis has been approved on the date shown below: / f ^ 7 3> CHARLES tD'MASON, Jr J Date Professor of Biological Saiences ACKNOWLEDGMENTS The author wishes to express his gratitude to D r • Charles T » Mason, Jr., for his time, thoughtful advice, and expert guidance throughout the graduate program. In addition, acknowledgment is given to the other members of his thesis committee, Drs. James W. O'Leary and Willard Van Asdall, who critically reviewed this paper and offered helpful suggestions. The author also thanks the sponsors who made the studies at The University of Arizona possible, such as the United States Agency for International Development (U.SoA.IoD.) and Universidade Federal do Ceara (U.F.C)/ University of Arizona (U.A«) Contracte The author's appreciation is also extended to Dr. W. G. Matlock, Campus Coordinator-Brazil Program and to his secretary Mrs. Evelyn Jorgensen, as well as his colleagues at the Departamento de Biologia do Centro de Ciencias da Universidade Federal do Ceara, Brazil, for their understanding and cooperation. Finally, the author owes a debt of gratitude to his wife, Aleuda, and children, Aleksey and Liana, who graciously relinquished some of the time they would have preferred to have spent with their husband and father. TABLE Of CONTENTS Page ABSTRACT v INTRODUCTION ......................... 1 PROCEDURE . , , . , . « . .. 3 KEY TO THE DIVISIONS « . « , . , , , . « . .• , 5 I . PTERIDOPHYTA .......... ' ^ . , , , 6 Key to the Families of Pterldophyta < «»,*<«,.«.. 6 II. SPERMATOPHYTA....................... 15 Key to the Classes of Spermatophyta« . .......... 15 Class I. GYMNOSPEREAE .................. 16 Key to the Families of Gymnospermae ......... 16 Class II. ANGIOSPERMAE.............. 18 Key to the Sub-classes of Anglospermae. ....... 18 Sub-class I. MONOCOTYLEDONEAE .............. 19 Key to the Families of Monocottyledoneae ....... 19 Sub-class II. DICOTYLEDONEAE. ..... 55 Key to the Series of Dicotyledoneae ......... 55 APPENDIX: NOMENCLATURE CHANGES. , . » . 260 LIST OF REFERENCES ......................... 274 iv ABSTRACT Rio Mayo Valley in Sonora, Mexico, is an area highly convenient for biological studies. A Sub-tropical zone between the Lower Sonoran and Upper Sonoran life zones is an important feature of this area» Plant collections in the valley have been made by many ex­ plorers. The most faithful record is the Gentry collection representing about 3200 specimens. His publication, Rio Mayo Plants, also, is the first one regarding geography, vegetation, plant census, succession and plant uses. This study was undertaken to provide a means for the identifi­ cation of the species cited by Gentry in his work through the Rio Mayo Basin. Keys are given to separate all taxa: 131 families, 532 genera, 1245 species, and 94 subspecific categories. An appendix is included to bring up-to-date the nomenclature for the taxa. v INTRODUCTION According to Gentry (31), the Rio Mayo with a drainage basin of about 17,648*26 square kilometers (6814 square miles) is one of the most important rivers in the State of Sonora, Mexico* Originating in the Sierra Madre of western Chihuahua, it discharges into the Gulf of Cali­ fornia 64 kilometers (40 miles) north of the boundary between Sonora and Sinaloa* The environmental combinations of climate, soil, drainage pat­ terns, geological history, and many other factors have markedly influ­ enced the vegetation in the valley, where Gentry (31) reports the most conspicuous natural feature is the presence of a subtropical zone as a northern extension of the tropics, between the Lower Sonoran and the Upper Sonoran life zones* An excellent description of the vegetation of the drainage area, of which the Mayo Valley is included, is given by Gentry (31), and provides good information about the plant census, succession, and use as well as the list of species that compose the flora * Since the area is suitable for biological studies plant collec- / tions have been made as early as the Carl Lumholtz Expedition of 1890, when Co V. Hartman and F* E* Lloyd went through the Sierra Madre from Bavispe Valley, in Sonora, to Casas Grandes, Chihuahua * Subsequent field work was undertaken by other explorers; however a catalogue of their collections and observations on the character or distribution of the vegetation has not been published (Gentry, 31)* 2 Forrest Shreve (in Gentry, 31) states that Gentry's collection made between 1933 and 1939 is one of the most faithful records of the flora of the Rio Mayo Basin. Gentry collected about 3200 specimens representing 1245 species and varieties, some of which have been deter­ mined as new. In his publication Rio Mayo Plants he brings together the records of the collections, observations on the distribution and composition of the vegetation, and information on the geography and physical features of the valley. He did not include keys for the iden­ tification of the plants listed in the flora * The chief purpose of this study, then, is to provide a means for identifying the species cited by Gentry in the account of his ex­ ploration through the Rio Mayo Valley. It is supposed, of course, that a paper such as this will add much to the usefulness of the book, and in addition, aid the many students having an interest in the flora and a need for the identification of the plants of the Rio Mayo Basin. PROCEDURE In order to attain the objective of the study5 keys are provided to the families, to the genera, and to the species. In a few instances the infraspecific categories of subspecies or variety are keyed„ The General Key follows that of Arizona Flora by Kearney and Peebles (63). The order of Families is that of Genera Siphonogamarum by Da11a Torre and Harms (18). Within the family the genera are ar- - . ranged alphabetically, except for Leguminosae, Gramineae and Compositae where they are arranged in Tribes or Subfamilies» The non indented Mdichotomous key" is employed throughout„ It can be short and limited to a single couplet, or it may be composed of an extensive series of these o The keys and descriptive data were, in general, adapted from Arizona, Flora by Kearney and Peebles (63), Trees and Shrubs of Mexico by Standley (145), Vegetation and Flora of the Sonoran Desert by Shreve and Wiggins (141), Flora of Guatemala by Standley and collaborators (146), Manual of the Vascular Plants of Texas by Correll and Johnston (15), Grasses of Southwestern United States by Gould (35), Manual of the Grasses of the United States by Hitchcock (47), Ferns and Fern Allies of Texas by Correll (14), Ferns and Fern Allies of Chihuahua, Mexico by Knobloch and Correll (67), and various monographs and revisions• Also, numerous portions of North American Flora by various authors were uti­ lized as sources of information for keys and descriptions* 4 Monographss revisions and portions of North American Flora are cited after the name of the taxon under consideration by number in pa­ rentheses. Citation of these publications5 correspondingly numbered3 is given in the list of References. Descriptions to families, genera, and species are:not included in this work. However, they will be found in the mentioned citation* General comments of each species to aid in the identification are given in Rio Mayo Plants under each specific name. The information includes distribution and abundance of each species in the Rio Mayo Valley, habitat preference of each species, and a brief description of the living plant, including its seasonal development. When possible Gentry supplied the common name applied to the plant by the Indians of the area as well as any use they made of it. Reference marks, * and -f, placed before any specific name indid­ eates it differs from that of Gentry’s book. The asterisk (*) indicates a change in nomenclature resulting from synonym, and the plus (+) indi­ cates the specimen was originally misidentifled. The nomenclatural changes are listed in alphabetical order in the appendix, and below each new name is the corresponding name in the booko KEY TO THE DIVISIONS 1. Fern or fernlike plants without true seeds; reproduction by means of spores. .............. .. I. PTERIDOPHYTA p. 6 1. Plants producing true seeds containing embryos ........... ........ .......... II. SPEKMATOPHYTA p. 15 ' 5 lo PTERID OPHYTA Key to the Families of Pteridophyta lo Leaves scale-like or elliptic to subulate3 sometimes coalesced into cylindrical sheaths around the stem.