Juan C. Ospina

Relict high-Andean ecosystems challenge our concepts of naturalness and human impact

What would current ecosystems be like without the impact of mankind? This question, which is critical for ecosystem management, has long remained unanswered due to a lack of present-day data from truly undisturbed ecosystems. Using mountaineering techniques, we accessed pristine relict ecosystems in the Peruvian Andes to provide this baseline data and compared it with the surrounding accessible and disturbed landscape. We show that natural ecosystems and human impact in the high Andes are radically different from preconceived ideas. Vegetation of these ‘lost worlds’ was dominated by plant species previously unknown to science that have become extinct in nearby human-affected ecosystems. Furthermore, natural vegetation had greater plant biomass with potentially as much as ten times more forest, but lower plant diversity. Contrary to our expectations, soils showed relatively little degradation when compared within a vegetation type, but differed mainly between forest and grassland ecosystems. At the landscape level, a presumed large-scale forest reduction resulted in a nowadays more acidic soilscape with higher carbon storage, partly ameliorating carbon loss through deforestation. Human impact in the high Andes, thus, had mixed effects on biodiversity, while soils and carbon stocks would have been mainly indirectly affected through a suggested large-scale vegetation change.

Morphology and leaf anatomy of Setaria s.l. (Poaceae: Panicoideae: Paniceae) and its taxonomic significance

Setaria is numerically one of the largest and most taxonomically complex genera of the tribe Paniceae. The currently published phylogenies of Setaria are not fully resolved and some of the resulting clades reveal more geographical signals than morphological affinities. Therefore, external similarities among species of Setaria do not generally indicate relationships, morphology appears to be highly labile, and few inferences can be made regarding the taxonomy of the genus. In the present study we analyze the variation of the foliar anatomy through a cluster analysis including morphological characters used traditionally to delimit subgenera, sections and species. The aim of this study is to examine whether foliar anatomy, a source of evidence not previously utilized, provides useful information and can be predictive for recognizing homogenous groups of species within Setaria. The significance of the characters is evaluated to identify species groups. These groups were compared with infrageneric taxa and monophyletic clades established in previously published molecular phylogenies. Additionally, some foliar anatomical characters associated with the photosynthetic pathway are also discussed and compared with other members of the tribes Paniceae and Paspaleae.

Multivariate Analysis and Taxonomic Delimitation within the Festuca setifolia Complex (Poaceae) and a New Species from the Central Andes

Abstract Taxonomic delimitation within the Andean Festuca setifolia complex s. l. has been fraught with difficulty due to the large range of morphoanatomical and epidermal variation among species coupled with varying opinions on what diagnostic characters should be used to distinguish species. We shed light on this through using multivariate analysis (PCA, PCoA and cluster analysis), based on 20 variables (morphoanatomical and epidermal characteristics), to elucidate patterns of variation within this group and to test the validity of current species delimitations. The analysis of 89 OTUs recognized six clearly separated groups, corresponding to F. fiebrigii, F. hieronymi, F. lilloi, F. linigluma (a new species described here), F. samensis, and F. setifolia. The OTUs corresponding to F. fiebrigii were grouped as outliers with respect to the F. setifolia complex s. l. and were excluded from multivariate analysis. We redefine the F. setifolia complex s. s. to include F. linigluma, F. lilloi, and F. setifolia, which possess unique characters differentiating them from other members of the complex s. l. The status of type material was clarified, with F. tucumanica synonimised under F. lilloi, while F. erecta var. mutica, F. erecta var. aristulata, and F. dissitiflora var. loricata, F. weberbaueri, F. dissitiflora var. villipalea, and F. hieronymi subvar. expansa were placed as synonyms of F. fiebrigii, with the taxonomic concept of F. fiebrigii being redefined. We present an identification key, descriptions, illustrations, and revised geographic ranges for F. fiebrigii and the species of the F. setifolia complex s. l., including the new species, Festuca linigluma, from the central Andes.

Sinopsis y novedades taxonómicas de la familia Marantaceae en la Argentina, incluyendo una nueva cita para el Paraguay

A synopsis and taxonomic novelties of the family Marantaceae in Argentina, including a new record from Paraguay. This synopsis of the Argentine species of Marantaceae includes six genera and seven species: Ctenanthe muelleri, Goeppertia eichleri, Maranta sobolifera, Saranthe eichleri, Stromanthe boliviana, Thalia geniculata, and T. multiflora. Species Ctenanthe muelleri is cited for the first time for Argentina and Paraguay, and Saranthe eichleri as a new record for Argentina. Ctenanthe casupoides var. subtropicalis is here synonymyzed within Saranthe eichleri. Lectotypes are designated for Calathea eichleri, C. macrostachya, Saranthe eichleri, and Thalia geniculata. Treatment of each species includes synonyms, iconography, vernacular names, observations, ethnobotany, geographical distribution, and habitat, and examined material. A key to the species, some illustrations and field photographs are also provided.

El género Galeandra (Orchidaceae) en Argentina

Galeandra (Orchidaceae) comprises about 18 species of epiphytic and terrestrial neotropical herbs. The genus is recognized by its flowers with funnel-shaped lip and spurred at the base. Four species of Galeandra have been recognized for the Argentinean flora in previous taxonomics studies: G. beyrichii, G. graminoides, G. hysterantha and G. styllomysantha. The aim of this contribution was to do a taxonomic treatment of Galeandra for Argentina. We recognize to G. beyrichii and G. xerophila, the last one is a new record for the argentinean flora. Galeandra graminoides and G. stylomisantha, are considered a doubtful report. The treatment includes an identification key, descriptions, geographic distributions data and habitat, field photographs, observations and comments on each species.

Nototriche chaniensis (Malvaceae), una Nueva Especie Poligámica de los Andes de la Argentina

Resumen. Se describe e ilustra a Nototriche chaniensis C. A. Zanotti & J. C. Ospina (Malvaceae), una nueva especie poligámica de los Andes de la Argentina. Nototriche chaniensis es morfológicamente afín a N. agyna Krapov., de la cual se diferencia principalmente por presentar el lóbulo central de la lámina entero, y la vagina y la porción libre del pecíolo de la hoja son de un largo considerablemente menor. Se incluyen la descripción, ilustración y fotos de la especie nueva. Se presenta una clave para diferenciar las especies poligámicas conocidas hasta el momento.