Arquitectura florial

Manual of Leaf Architecture
Morphological description and categorization of dicotyledonous and net-veined monocotyledonous angiosperms

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©1999 by Smithsonian Institution.
All rights reserved. Published and distributed by: Leaf Architecture Working Group c/o Scott Wing Department of Paleobiology Smithsonian Institution 10th St. & Constitution Ave., N.W. Washington, DC 20560-0121

ISBN0-9677554-0-9 Please cite as: Manual of Leaf Architecture - morphological description and categorization of dicotyledonous and net-veined monocotyledonous angiosperms by Leaf Architecture Working Group. 65p. Paper copies of this manual were printed privately in Washington, D.C. We gratefully acknowledge funding from Michael Sternberg and Jan Hartford for the printing of this manual.

-2-Names and addresses of the Leaf Architecture Working Group in alphabetical order:

Amanda Ash Department of Paleobiology Smithsonian Institution NHB 10th St. & Constitution Ave, N.W. Washington, DC 20560-0121 Telephone: 202 357-4030 Fax: 202 786-2832 Email: ash.amanda@nmnh.si.edu

Beth Ellis 1276 Cavan St. Boulder, CO 80303 Telephone: 303 666-9534 Email: Beth@displaytech.com

Leo J. HickeyDivision of Paleobotany Peabody Museum of Natural History Yale University 170 Whitney Avenue, P.O. Box 208118 New Haven, CT 06520-8118 Telephone: 203 432-5006 Fax: 203 432-3134 Email: leo.hickey@yale.edu

Kirk Johnson Department of Earth and Space Sciences Denver Museum of Natural History 2001 Colorado Boulevard Denver, CO 80205-5798 Telephone: 303 370-6448 Fax: 303 331-6492 Email:kjohnson@dmnh.org

Peter Wilf University of Michigan Museum of Paleontology 1109 Geddes Road Ann Arbor, MI 48109-1079 Telephone: 734 763-9373 Fax: 734 936-1380 Email: pwilf@umich.edu

Scott Wing Department of Paleobiology Smithsonian Institution NHB 10th St. & Constitution Ave, N.W. Washington, DC 20560-0121 Telephone: 202 357-2649 Fax: 202 786-2832 Email: wing.scott@nmnh.si.edu

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INTRODUCTION
Sincethe time of Linnaeus the identification and reconstruction of relationships between plants have been based largely on features of the reproductive organs. Although flower and fruit characters have proved very useful in both botany and paleobotany, there are situations in which these organs are not available for study. For example, leaf compression and impression fossils are the most commonmacroscopic remains of plants, but they are generally not attached to other plant organs. Because of their abundance and dense stratigraphic occurrence, fossil leaves can provide an enormous amount of information about the composition and diversity of past floras - if they can be used to recognize species reliably and assign them to higher taxa. Tropical botanists also find themselves confronted withthe need to identify and classify plants using vegetative characters because so many long-lived tropical plants flower infrequently and irregularly. In spite of the success of Linnaeus’s sexual system and its descendants, there is a great need to be able to identify and classify dispersed leaves. The overall purpose of this manual is to help you do that. The problem of working with isolated leavesis a long-standing one in paleobotany. Lacking both an accepted system of terms for describing leaf form, and a knowledge of the systematic distribution of leaf features among living angiosperms, and in many cases faced with poorly preserved fossils, most early workers focused on overall characters of leaf shape and size that ultimately have not proven very useful in recognizing species or highertaxa. Names of living genera were widely applied to fossils so that there are, for example, many taxonomically valid fossil species of Ficus, Populus, and Aralia based on poorly preserved leaves with only vague similarities to the living members of these genera. Late nineteenth and early twentieth century angiosperm paleobotanists left a legacy of poorly defined taxa with botanically misleading...