SUSANA VALENCIA-A.1*, GABRIEL FLORES-FRANCO2, JAIME JIMÉNEZ-RAMÍREZ1 Y MAURICIO MORA-JARVIO3 Botanical Sciences 95 (4): 660-721, 2017 Abstract Background: The family Fagaceae is one of the most important in temperate regions of the Northern DOI: 10.17129/botsci.1020 hemisphere. Fagus and Quercus are distributed in Mexico, the former in Northeastern Mexico, while the latter reaches a high diversity in the Sierra Madre Oriental, Mexico. In Hidalgo state, located mainly in the Received: Sierra Madre Oriental, knowledge of the Fagaceae diversity is still uncertain. November 14th, 2016 Questions and/or hypothesis: We carried out a taxonomic revision of the genus and species of Fagaceae Accepted: in Hidalgo state. We determined how many and which species are distributed in Hidalgo. We also present April 20th, 2017 a morphological description and ecological characters of each one. Associate Editor Studied species: The species of the family Fagaceae. Juan Núñez Farfán Study site: Hidalgo state, Mexico. Method: We collected herbarium specimens, made feld observations and reviewed herbarium data of Fagaceae specimens at FCME, INEGI, MEXU, ENCB, SLPM, HUAP, HUMO, XAL and partly BH her- baria. In addition, we checked taxonomic literature and protologues of each species. Results: We found one species of Fagus and 43 of Quercus, 22 of which belong to the section Quercus (white oaks) and 21 to section Lobatae (red oaks). Morphological descriptions, altitudinal and geographi- cal distribution, vegetation types of each species and a dichotomous key for species identifcation are presented. Illustrations and photographs of the species are also included. Conclusions: A high diversity of Fagaceae species is present in Hidalgo state. In Mexico, Hidalgo ranks Copyright: © 2017 Valencia-A et al. in ffth place for oak species diversity, just behind Oaxaca (50 species), Puebla (50), San Luis Potosí (45), This is an open access article distri- and Jalisco (45). buted under the terms of the Creati- Keywords: Fagus, Quercus, foristics, Hidalgo state, Mexico. ve Commons Attribution License, which permits unrestricted use, dis- tribution, and reproduction in any Resumen medium, provided the original author Antecedentes: La familia Fagaceae es una de las más importantes en las regiones templadas del Hemisfe- and source are credited. rio Norte. Fagus y Quercus se distribuyen en México, el primero en el noreste, el último alcanza una gran diversidad en la Sierra Madre Oriental, México. En el estado de Hidalgo, ubicado principalmente en la 1 Universidad Nacional Autónoma Sierra Madre Oriental, el conocimiento de la diversidad de la familia Fagaceae es aun incompleto. de México, Departamento de Preguntas y/o hipótesis: Realizamos una revisión taxonómica de los géneros y las especies de la familia Biología Comparada, Herbario Fagaceae en el estado de Hidalgo. Determinamos cuántas y cuáles especies se distribuyen en Hidalgo. de la Facultad de Ciencias, También presentamos descripciones morfológicas y datos ecológicos de cada especie. Ciudad Universitaria, Circuito Species estudiadas: Las especies de la familia Fagaceae. exterior s.n. Coyoacán 04510, Sitio de estudio: Estado de Hidalgo, México. Ciudad de México, Mexico 2 Universidad Autónoma del Método: Colectamos ejemplares para herbario, hicimos observaciones de campo para las especies y re- Estado de Morelos. Centro de visamos los ejemplares de Fagaceae depositados en los herbarios FCME, INEGI, MEXU, ENCB, SLPM, Investigaciones en Biodiversidad HUAP, HUMO, XAL y parcialmente en BH. Adicionalmente revisamos la literatura taxonómica y los y Conservación (CIByC). protólogos para cada especie. 3 Universidad Nacional Autónoma Resultados: Encontramos una especie de Fagus y 43 de Quercus, 22 de las cuales pertenecen al section de México, Departamento de Quercus (encinos blancos) y 21 a section Lobatae (encinos rojos). Se presentan descripciones morfológi- Botánica, Instituto de Biología, cas, datos de distribución altitudinal, geográfca y por tipos de vegetación para cada especie; así como una Ciudad Universitaria, Coyoacán clave dicotómica para su identifcación. También se incluyen ilustraciones y fotografías de las especies. 04510, Ciudad de México, Mexico Conclusiones: El estado de Hidalgo contiene una alta diversidad de especies de Fagaceae. Esta entidad * Corresponding author: svalen- ocupa el quinto lugar de diversidad de Fagaceae después de Oaxaca (50 especies de encinos), Puebla (50), [email protected] San Luis Potosí (45) y Jalisco (45). Palabras clave: Fagus, Quercus, forística, estado de Hidalgo, México. 660 SUSANA VALENCIA-A. ET AL. agaceae is one of the most important families of Angiosperms in the temperate regions of the Northern hemisphere. It comprises 10 genera: Lithocarpus, Trigonobalanus, Colombobalanus, Formanodendron, Chrysolepis, Castanea, Castanopsis, Quercus, Fagus (Nixon & Crepet 1989) F and the recently segregated genus Notholithocarpus (Manos et al. 2008). In Mexico Quercus is represented by 161 of the 500 species known worldwide (Manos et al. 1999, Valencia-A. 2004, Aldrich & Cavender-Bares 2011). Later, Villaseñor (2016) cited 174 names of species of Quercus in Mexico. But for Fagus only F. grandifolia subsp. mexicana (Martínez) E. Murray is present in the country, in small populations in the states of Hidalgo, Nuevo León, Puebla, San Luis Potosí, Tamaulipas and Veracruz (Rodríguez-Ramírez et al. 2013). The state of Hidalgo is located in the central region of Mexico (INEGI 1992, Figure 1), one of the richest in oak species diversity (Nixon 1993, Valencia-A. 2004; Valencia-A. & Gual-Díaz 2014), which has motivated the study of the genus Quercus in certain locations of the state and the discovery of several new species. During the 19th Century, many species of this genus were described, including Quercus castanea Née, Q. elliptica Née (Née 1801), Q. laurina Bonpl., Q. depressa Bonpl., Q. repanda Bonpl. (Bonpland 1809), Q. affnis Scheidw. (Scheidweiler 1837) and Q. glabrescens Benth. (Bentham 1840). In the 20th Century, Trelease (1924) described Q. alpescens Trel., Q. opaca Trel., Q. toxicodendrifolia Trel. and Q. trinitatis Trel., all of them from Hidalgo. Martínez (1940) described Fagus mexicana. Zavala-Chávez (1995) studied the oaks of the Parque Nacional El Chico, where he docu- mented 20 species of Quercus and later published Q. pachucana Zavala (Zavala-Chávez 2000) as a new species. Valencia-A. & Cartujano-P. (2002) registered Q. pinnativenulosa C.H. Mull. in the state of Hidalgo and Vázquez et al. (2004), described Q. hirtifolia as a new species based on material collected in the same state. Álvarez-Zúñiga et al. (2010) registered 18 species of oaks in the Parque Nacional Los Marmoles, and Valencia et al. (2011) described Q. delgadoana based on the type specimen collected in Hidalgo. Even though there are several studies on this matter, a comprehensive taxonomic and foristic study of this genus in the state of Hidalgo is still missing. In addition, the continuous forest fragmentation, especially of the woodlands in the main montain regions of Mexico, and the scarce botanical knowledge of the family and genus in eastern Mexico emphasize the importance of studying these taxa in the state of Hidalgo. The aim of this study is to contribute to the taxonomic knowledge of the Fagaceae in the state of Hidalgo. We present a specifc foristic list and identifcation keys for genera and species, with the corresponding descriptions and general distribution of each species within the state. Study zone. According to INEGI (2014), the state of Hidalgo is located between 19° 36’ and Author contributions 21° 24’ North and 97° 58’ and 99° 53’ West. The area of the state is approximately 20,813 km2, Susana Valencia-A. Conceived representing 1.1 % of the total surface of Mexico. The state is divided into 84 municipalities, the original idea, planned the and shares its borders with San Luis Potosí (North), Veracruz (Northeast), Puebla (Southeast), development of the study of Fagaceae in Hidalgo state, Tlaxcala (South), Estado de Mexico (South) and Querétaro (West). The altitude within the collected botanical speci- state ranges from 180 m in the canyon of the Sierra Madre Oriental, in the province of Carso mens, wrote the descriptions Huasteco, and up to 3,350 m in the Cerro La Peñuela, located in the southwestern region of of species and wrote the the state. manuscript. There are three physiographic provinces in the state: a) The Sierra Madre Oriental in the Gabriel Flores-Franco planned northern region of the state, covering approximately 62 % of the total surface; b) the Trans- and conducted the collection Mexican Volcanic Belt at the south, with 37.4 % of the total surface, and c) the Mexican Gulf of botanical specimens of Coastal Plain at the northeastern region, with a 0.27 % of the total surface. familiy Fagaceae in Hidalgo. Due to its location and physiography, three main climates are recognized: tropical and sub- He also provided ecological characters for each species tropical climates are present in the lower portions of the Sierra Madre Oriental facing the Gulf and reviewed herbaria. of Mexico; temperate and semi-temperate climates occur in the highlands of the Sierra Madre Jaime Jiménez-Ramírez wrote Oriental and Trans-Mexican Volcanic Belt; arid and semi arid climate characterize the Metztit- the descriptions and reviewed lan Canyon and the Central Meseta of Hidalgo (Martínez-Morales et al. 2007). the literature. Besides of the aquatic vegetation fourishing in the lakes, rivers and lagoons,