591 TAXON 67 (3) • June 2018: 591–605 Borges & al. • Selecting types from Ernst Ule collections Version of Record Article history: Received: 5 May 2017 | returned for (first) revision: 10 Aug 2017 | (last) revision received: 3 Apr 2018 | accepted: 3 Apr 2018 | published: online fast track, 4 Jun 2018; in print and online issues, 6 Jul 2018 || Associate Editor: James C. Lendemer || © International Association for Plant Taxonomy (IAPT) 2018, all rights reserved INTRODUCTION One of the principles of the International Code for Nomenclature for algae, fungi, and plants (ICN ) is that “the application of names of taxonomic groups is determined by means of nomenclatural types” (McNeill & al., 2012: 23). This concept was officially established in 1935, with inclusion of the “type- method” in the Cambridge Rules (Harms, 1935; Rijckevorsel, 2014). Hence, most new species descriptions made before that date do not include explicit type designations. Nonetheless, some- times it is possible to consider a particular specimen belonging to a certain herbarium as the holotype, especially when the author clearly stated that it was the only one studied (Prado & al., 2015; but see McNeill, 2014). For other situations, it is possible to select a lectotype based on original material studied and used to describe the species (McNeill & al., 2012). Between the time of publication of Species plantarum (Linnaeus, 1753) and the establishment of the Cambridge Rules (Harms, 1935), a great number of plant names were published without explicit designation of types. Therefore, many names must be typified. Among these are a multitude of Brazilian spe- cies, many of which were collected and described only after the opening of the country to foreign botanists with the arrival of the Portuguese royal family in the beginning of the 19th century (Pires-O’Brien, 1993). Specimens from Brazil were collected by many explorers, for example Ludwig Riedel, Carl F.P. von Martius, Friedrich Sellow, William J. Burchell, and Auguste F.M. Glaziou, to name only a few (Urban, 1906). Among later botanical explorers was Ernst Ule, who collected in Brazil A tale of traded specimens, or what to know when selecting types from Ernst Ule’s collections Leonardo M. Borges, 1 Matthias Schultz, 2 Hans-Helmut Poppendieck, 2 Jacquelyn A. Kallunki3 & Marcelo Trovó4 1 Universidade Federal de São Carlos, Departamento de Botânica, Rodovia Washington Luís, Km 235, São Carlos, SP, 13565-905, Brazil 2 Herbarium Hamburgense, Biocenter Klein Flottbek, University of Hamburg, Ohnhorststr. 18, 22609 Hamburg, Germany 3 The New York Botanical Garden, Bronx, New York 10458-5126, U.S.A. 4 Departamento de Botânica, Instituto de Biologia, Universidade Federal do Rio de Janeiro, CCS, Bloco A1, Cidade Universitária, Rio de Janeiro, RJ, 21941-590, Brazil Author for correspondence: Leonardo M. Borges, aquitemcaqui@gmail.com DOI https://doi.org/10.12705/673.10 Abstract Many Brazilian plant names are based on specimens gathered by European naturalists working in the 19th and early 20th centuries. Among these explorers is Ernst Ule, a German naturalist who collected profusely in Brazil. Ule’s specimens were largely used to publish names before the need to indicate types for valid publication and, hence, many of those names need to be typified. Because typification is not always a straightforward process, we use examples from Mimosa and Paepalanthus to show how an understanding of the historical background of these collections is necessary to support nomenclatural work with names based on specimens he gathered. We present a set of guidelines for typification of names based on his collections and, as examples, we provide lectotypifications for 35 species of Mimosoid legumes. Keywords Eriocaulaceae; herbarium; Herbarium Berolinense; Herbarium Hamburgense; Leguminosae between 1883 and 1912 (Harms, 1915). During his lifetime as a collector, Ule made about 17,000 collections, that represented different groups of embryophytes, fungi, and lichens. Most of these collections were made in Brazil, but some were collected in Peru or in areas that at the time belonged to Bolivia (chiefly the Brazilian state of Acre) (Harms, 1915). Ule’s collections were subsequently used as the basis for the descriptions of a large number of taxa. We estimate that about 1200 collections are types of vascular plants, 600 are types of bryophytes (Walther & Martienssen, 1976) and 750 are types of fungi (Friedrichsen, 1973). The descriptions of many of these taxa, however, were published before the establishment of the type-method, thus the names frequently require typification. Here we present historical data that sheds light on issues per- taining to the distribution and deposition of Ule’s collections. We also provide a set of guidelines to aid in the typification of names based on these collections, mostly based on study of Mimosoids (Leguminosae), particularly Mimosa L. (Linnaeus 1753), and Paepalanthus Mart. (Martius, 1834) (Eriocaulaceae). We also present, as examples for the application of the Guidelines, lecto- typifications for 35 species of Mimosoids. ERNST ULE: A BRIEF HISTORY Ernst Heinrich Georg Ule (Fig. 1) was a botanist and ex- plorer who became one of the most prominent plant collectors in Brazil and Amazonian Peru. His life, particularly his pro- fessional life, has been portrayed by several authors (Taubert,