Prado, Darién E.2018-09-032018-09-032016-12-13http://hdl.handle.net/2133/12170El género Celtis L. (Celtidaceae) comprende alrededor de 70 especies de árboles o arbustos, distribuidos en regiones templadas y tropicales del mundo. La variabilidad y similitud inter e intraespecíficas, han generado numerosas confusiones taxonómicas y nomenclaturales dentro del grupo. Uno de los casos más emblemáticos, y que forma parte de la flora argentina, es el de Celtis ehrenbergiana (Klotzsch) Liebm., considerado un taxón muy amplio y que engloba a C. pallida Torr. y a C. tala Gillies ex Planch., a pesar de que, y tal como lo han sostenido varios autores en el pasado, se trataría de entidades claramente diferenciables a campo. Por ello, a través de un extenso muestreo y un estudio morfológico detallado, se planteó llevar a cabo la revisión taxonómica de dichos taxones. Mediante Análisis de Componentes Principales y de Conglomerados, sobre 48 especímenes y 46 caracteres morfológicos, se evidenció claramente que C. ehrenbergiana comprende tres entidades diferentes: C. tala, C. pallida var. pallida y C. pallida var. discolor Hunz. & Dottori, tal como se planteó en la hipótesis original. Los resultados del Análisis de la Varianza (PERMANOVA) y de Similitud (ANOSIM) corroboran diferencias significativas (p-valor < 0.05) entre los grupos. Se establecieron como caracteres de importancia taxonómica a: porte de los individuos, textura de la corteza, pilosidad de láminas, nervaduras y pecíolos, espinas estipulares/ramas espinosas, y abundancia y aspecto de los domacios. Además, se encontraron especímenes de C. pallida morfológicamente intermedios entre las variedades, postulándose la hipótesis de posible hibridación en las áreas de contacto. Esto sugiere la necesidad de que futuros estudios en Celtis contemplen el uso de herramientas moleculares. Finalmente, se provee de información biogeográfica, imágenes, una clave dicotómica de ayuda para la determinación de los taxones estudiados, así como también del tratamiento nomenclatural correspondiente a cada entidad.The genus Celtis L. (Celtidaceae) comprises around 70 tree or shrub species, distributed in temperate and tropical regions of the world. Its morphological variability and similarities inter and intraspecific, has generated numerous taxonomic and nomenclatural confusions within the group. One of the most emblematic such cases in Argentine flora is Celtis ehrenbergiana (Klotzsch) Liebm., considered a very wide taxon encompassing C. pallida Torr. and C. tala Gillies ex Planch., despite that several authors in the past have sustained that they are clearly separable entities in the field. Thus, a taxonomic revision of these entities set off, through an extensive field sampling and a detailed morphological study. By means of Principal Component Analysis and Conglomerate Analysis on 48 specimens and 46 morphological characters, it was clearly evinced that C. ehrenbergiana comprises three different entities: C. tala, C. pallida var. pallida and C. pallida var. discolor Hunz. & Dottori, as it was postulated in the original hypothesis. The Variance Analysis (PERMANOVA) and Similarity (ANOSIM) results corroborate significative differences (p-valor < 0.05) amongst the groups. The following taxonomical relevant characters were established: habit of the individual, bark texture, pubescence of blades, nerves and petioles, stipular spines/spiny branches, abundance and aspect of domacia. Moreover, some morphologically intermediate individuals were found amongst both C. pallida varieties, and therefore a hypothesis of potential hybrization in the contact areas. This suggests the need of the use of molecular tools in future studies in Celtis. Finally, biogeographical information, images, a dichotomic key to determine the studied taxons are provided, along with the nomenclatural treatment corresponding to each entity.The genus Celtis L. (Celtidaceae) comprises around 70 tree or shrub species, distributed in temperate and tropical regions of the world. Its morphological variability and similarities inter and intraspecific, has generated numerous taxonomic and nomenclatural confusions within the group. One of the most emblematic such cases in Argentine flora is Celtis ehrenbergiana (Klotzsch) Liebm., considered a very wide taxon encompassing C. pallida Torr. and C. tala Gillies ex Planch., despite that several authors in the past have sustained that they are clearly separable entities in the field. Thus, a taxonomic revision of these entities set off, through an extensive field sampling and a detailed morphological study. By means of Principal Component Analysis and Conglomerate Analysis on 48 specimens and 46 morphological characters, it was clearly evinced that C. ehrenbergiana comprises three different entities: C. tala, C. pallida var. pallida and C. pallida var. discolor Hunz. & Dottori, as it was postulated in the original hypothesis. The Variance Analysis (PERMANOVA) and Similarity (ANOSIM) results corroborate significative differences (p-valor < 0.05) amongst the groups. The following taxonomical relevant characters were established: habit of the individual, bark texture, pubescence of blades, nerves and petioles, stipular spines/spiny branches, abundance and aspect of domacia. Moreover, some morphologically intermediate individuals were found amongst both C. pallida varieties, and therefore a hypothesis of potential hybrization in the contact areas. This suggests the need of the use of molecular tools in future studies in Celtis. Finally, biogeographical information, images, a dichotomic key to determine the studied taxons are provided, along with the nomenclatural treatment corresponding to each entity.application/pdfspaopenAccessCeltis (Cannabidaceae)Chaco (Argentina)TaxonomíaAnálisis multivariadoPropiedades biológicasCaracteres vegetativosbachelorThesisJorgelina Pamela Asmus