From Plant Press, Vol. 14, No. 1 from January 2011.
The following botanists visited the U.S. National Herbarium with the support of a 2010 Cuatrecasas Award.
Fabio Ávila
Fabio Ávila, from the Universidad Distrital in Bogota, Colombia, visited for a month (18 October – 19 November). He identified, evaluated, and circumscribed the species of the neotropical genus Lasiocephalus Willd. ex Schltdl., within the Senecioneae group of Compositae. Since the last reinstatement by Cuatrecasas in 1974, the genus has been without new advances in its systematic. In this way, he is supporting in the taxonomy of the genus for further advances in its phylogeny. His previous research was conducted at the Charles University in the Czech Republic. During his stay, Ávila revised about 400 specimens and the type collections of four species of Lasiocephalus. In his revision, he proposed the synonyms by locating two names published in the former work of Cuatrecasas: L. caldasensis and L. mochensis, in L. involucratus and L. loeseneri, respectively. Thus, he could confirm the identity of 12 species for Colombia and circumscribe the genus to 20 names in the tropics. He also corrected the older names, since the group was taxonomically considered within Senecio. In addition, he achieved to recognize the morphologic variation of the complex L. otophorus, under infra-specific categories by Cuatrecasas. Ávila’s research will contribute to the phylogeographic studies in that species in the Andean Range. Finally, the Cuatrecasas Fellowship has made it possible to review all the variation of the genus from Venezuela to Bolivia, and supported the last steps for a next issue of the Flora of Colombia.
The leaf morphotype GD5 from the Guaduas Formation of the Late Cretaceous of Columbia is the focus of Camila Martínez Aguillón's research.
The research of Camila Martínez Aguillón, from the Universidad de los Andes, Colombia, focuses on dating of plant phylogenies based on the fossil record and molecular data, biogeographical reconstructions and the diversification processes in the Neotropics. Her Master’s thesis focuses on the identification of a leaf morphotype called GD5 from the Guaduas Formation of the Late Cretaceous of Colombia, based on morphological and anatomical characters. During her visit to the Smithsonian, Martínez Aguillón focuses on the identification of leaf morphotypes and a broad revision of the overall morphology of angiosperms that present a similar morphology as the morphotype GD5 (below). Some of the genera that she revised belong to Menispermaceae, Aristolochiaceae, Fabaceae, Euphorbiaceae and Piperaceae. Once the revision of the cleared leaves was completed, she concluded that the Piperaceae shared more characters with the fossil than any of the other families. She made a bibliographic revision of previous macrofossils associated with the family and fortunately three of them were stored in the U.S. paleobotanical collection. Martínez Aguillón then made a wide revision of the order Piperales, including other genera of the families Aristolochiaceae, Hydnoraceae and Saururaceae. Within Piperaceae she evaluated the genera Zippelia, Manekia and Verhuellia. Given that Piper is a pantropical genus with around 2,000 species, she decided to describe the leaf architecture of the genus, based on approximately 320 species previously sampled to construct the molecular phylogeny. She started the evaluation of the genus Piper with the paleotropical clades and then she continued with the less representative clades. Once the description of the leaves is completed and the taxonomic affinity of the fossil is established, she will calibrate the phylogeny of the genus and try to elucidate the origin and the migration of the genus.
Carlos Alonso Maya Lastra
Carlos Alonso Maya Lastra, a graduate student from Universidad del Quindío, Colombia, conducted studies on the taxonomy of the genus Dalechampia (Euphorbiaceae). He analyzed more than 600 collections of Dalechampia from the Neotropics and 57 specimens from Colombia. Overall, he has studied 320 collection of Dalechapia for Colombia from 13 different herbaria, with the material from US corresponding to 15.2 percent of the total sample, which covers a large time span contributing greatly to his work. Through the study of general collections and types he was been able to clarify numerous species concepts and understand their distributional patterns and morphological variation. Maya Lastra was able to uncover collections representing undescribed species and verify new synonymy and range extensions. He also benefited from using the large collections of literature housed in the Botany Library.
Maria Alejandra Jaramillo
Maria Alejandra Jaramillo, from Universidad Icesi, Cali, Colombia, conducted research on the “Geographic Differentiation of Piper Species Complexes along the Chocó Region and Central America.” She examined herbarium specimens, including several type specimens, as well as consulted the library and made copies of protologs of all species and their synonyms. She compiled a database with all specimens belonging to the Piper trianae (Piperaceae) complex. The database includes geographic information for 350 entries—of which the data will be used to produce distribution maps and predicted localities that need to be visited for a through sampling. A portion of leaf tissue was taken from selected specimens (with permission) to include in future molecular phylogenetic analyses. Many species of this complex are only known from the type collection. In particular a number of them correspond to collections made by José Cuatrecasas during his expeditions in Valle del Cauca, Colombia. Type specimens of nine of the 16 species of the complex are at US. Jaramillo also examined specimens of other clades of Piper, i.e. Ottonia and Enckea. She was able to identify at least two new species, one from Ecuador (a very distinct taxon of the Peltobryon clade with peltate leaves) and another from Guyana, belonging to the Ottonia clade.
From 16 September to 2 October, Ana Isabel Vásquez-Vélez, from Universidad del Valle, Cali, Valle del Cauca, Colombia, studied 70 species of Pilea Lindl. (Urticaceae), 25 of which are distributed in Central America and 45 in South America. These included 91 types, 29 of which are from Central America and 62 from South America, including 31 from Colombia. She built a database recording numerous morphological characters that are useful in the classification of the genus. These include length of masculine and feminine inflorescences, flower size, number of tepals, size of flower clusters, fruit size; size and shape of leaf cystoliths; stipule size; and presence or absence of pubescence. In total, she was able to study and identify about 200 specimens of Neotropical Pilea.
Ana Isabel Vásquez-Vélez
The dissertation objectives of José D. Zúñiga, from the Rancho Santa Ana Botanic Garden and Claremont Graduate University, include phylogenetic studies within Sabiaceae and Meliosma, as well as taxonomic work on Neotropical Meliosma. The Cuatrecasas Fellowship allowed him to study the morphological variation of vegetative and reproductive characters in Meliosma, with focus on subgenus Meliosma sect. Lorenzanea, and to study the type collections of Sabiaceae. Zúñiga studied over 30 type specimens of Neotropical Meliosma and three belonging to Ophiocaryon species. Notes and measurements on reproductive and vegetative morphological features were made for each specimen. When present, flowers were rehydrated and dissected with a light microscope (with previous consent from herbarium staff) to document with detail floral morphological characters that are of taxonomic importance in these two genera. He gathered label data from type specimens and general collection specimens. This data is already being used to inform future field work. He also annotated the specimens of Central American Meliosma.