Andean Forests Research Articles

Liparis inaudita (Orchidaceae, Malaxidinae), a new species from the Bosque de Protección Alto Mayo, San Martín, Peru

Background: During an ongoing inventory of the orchids of the Bosque de Protección Alto Mayo, northern Peru, a population morphologically assignable to Liparis section Decumbentes was found. This is a little-known group restricted to wet montane Andean forests and consists of four species, from which the BPAM populations differs in leaf and labellum morphology.
 Hypotheses: The features of the plants led us to hypothesize that it represents an unknown species, which can be distinguished morphologically from its congeners.
 Taxon: Liparis section Decumbentes , Liparis sp. nov.
 Study site and dates: Peru, department of San Martín, Rioja province, Pardo Miguel Naranjos district, Bosque de Protección Alto Mayo, sector Venceremos.
 Methods: The unknown entity was studied in detail using fresh, pressed, and alcohol-preserved specimens. We also compared it to type specimens, other specimens of Liparis section Decumbentes housed in herbaria in Peru and abroad, and with descriptions from specialized literature.
 Results: A leaf feature and the unique labellum morphology of the unknown entity permit it to be distinguished clearly from all other species of Liparis section Decumbentes .
 Conclusions: The new species shares with L. sessilis the sessile leaf blades and the convex labellum, but differs from it and all other species of the section in its saddle-shaped labellum, which when spread out is narrowly obtrapezoid, with minute basal auricles, laciniate distal margins, and the apex projected into a narrowly triangular lobe.

New altitudinal records of Panthera onca (Carnivora: Felidae) in the Andean region of Ecuador

Abstract We report two records of jaguars (Panthera onca) registered with camera traps at 2300 and 2660 m a.s.l. in the Ecuadorian Andes, which represent the first verifiable records of the species above 2000 m in Ecuador. As the first records of jaguars from Río Negro-Sopladora National Park and Tapichalaca Reserve, these records raise important questions about the species’ ecology and conservation in Andean montane forests. From a regional perspective, these records may indicate connectivity between jaguar populations inhabiting both sides of the Andes. Sustained monitoring of wildlife populations is necessary to discern the significance of these records and help develop strategies to ensure the conservation of this highly mobile species across the increasingly fragmented Andean-Amazonian landscapes of southern Ecuador.

Soil Fungal Diversity of the Aguarongo Andean Forest (Ecuador).

Simple SummaryThe Kingdom Fungi is one of the richest in species, most of which are still unknown. Many fungal species are hidden in the tropics, the area richest in biodiversity on earth. In this paper, a mycological analysis is presented on a vast number of soil samples collected in the Aguarongo forest, an important Andean Natural Reserve of Ecuador. The study was carried out by analyzing the total DNA extracted from the soil and unveiled a total of more than 400 species of fungi. The most abundant species belong to Ascomycota and Mortierellomycota; some are important beneficial fungi for the environments such as antagonistics of fungal pathogens or nematode predators, while others are well-known producers of nutraceutical and pharmaceutical compounds. Based on the results of this study, a picture of the mycodiversity of Aguarongo forest soil was obtained. This area hides a huge number of unknown fungal species that could be discovered; thus, the protection of the Aguarongo forest is mandatory.Fungi represent an essential component of ecosystems, functioning as decomposers and biotrophs, and they are one of the most diverse groups of Eukarya. In the tropics, many species are unknown. In this work, high-throughput DNA sequencing was used to discover the biodiversity of soil fungi in the Aguarongo forest reserve, one of the richest biodiversity hotspots in Ecuador. The rDNA metabarcoding analysis revealed the presence of seven phyla: Ascomycota, Basidiomycota, Mortierellomycota, Mucoromycota, Glomeromycota, Chytridiomycota, and Monoblepharomycota. A total of 440 identified species were recorded. They mainly belonged to Ascomycota (263) and Basidiomycota (127). In Mortierellomycota, 12 species were recorded, among which Podila verticillata is extremely frequent and represents the dominant species in the entire mycobiota of Aguarongo. The present research provides the first account of the entire soil mycobiota in the Aguarongo forest, where many fungal species exist that have strong application potential in agriculture, bioremediation, chemical, and the food industry. The Aguarongo forest hides a huge number of unknown fungal species that could be assessed, and its protection is of the utmost importance.

Turnover-driven loss of forest-dependent species changes avian species richness, functional diversity, and community composition in Andean forest fragments

Andean forests, a hotspot of biodiversity, have suffered extensive fragmentation, yet we have little understanding of how this process has affected biodiversity. We surveyed bird communities across a gradient of fragment sizes (10–170 ha) and a continuous forest reference site in the Colombian Western Andes. Using a multi-species occupancy model to combine survey data from audio-visual transect surveys, mist netting, and playbacks for owls, we estimated alpha and beta taxonomic and functional diversity. We asked whether (1) habitat amount (patch size), edge effects, or selective logging affect bird occupancy and drive changes to diversity, (2) functional and taxonomic diversity respond similarly to fragmentation, and (3) compositional changes result from species turnover or nested species loss. Species richness declined with decreasing habitat amount, increasing edge density, and increasing disturbance through selective logging. These effects were driven by the loss of forest-dependent species, which were also area sensitive: 30 such species were absent from fragments, even the largest ones (>150 ha). Area-sensitive species were also edge sensitive and increased in occupancy in unlogged forest. We further found high beta diversity (0.78) driven by species turnover (85% of dissimilarity) along the gradient. Despite extensive turnover to non-forest species within functional groups, functional trait richness and dispersion significantly declined with habitat amount. Small fragments may mimic the structure and composition of early-successional Andean forests, driving spatial turnover patterns favoring disturbance-adapted species at the expense of primary-forest specialists. Large forest reserves are therefore required to conserve forest-dependent Andean birds.

Responses of functional traits in cavity-nesting birds to logging in subtropical and temperate forests of the Americas

Logging causes changes in habitat structure, which can potentially lead to variations in taxonomic and functional richness of biodiversity. Studies on how functional traits in birds are affected by logging operations can provide an important element for the understanding of ecosystem processes. In this paper, we examined how logging in subtropical Andean forests influenced taxonomic and functional diversity of cavity-nesting birds. We used these results to compare how logging affected ecosystem functions in temperate and subtropical forests of the Americas. We used point-counts to examine the effects of logging on taxonomic and functional traits in avian communities (Functional Richness, Functional evenness, Functional Divergence, and Community-weighted mean). We found that logging changed bird richness and abundance, although it had no effect on the functional response to the measured traits. The comparison of our results with those of temperate forests of Canada and Chile reveals differences in the functional richness of birds in these habitats, with a lower impact of logging on functional traits. We highlight the importance of including functional traits in the analyses, since the reduction in the species richness and abundance may not be translated into functional changes within the ecosystem.

Riqueza de las plantas vasculares del bosque altoandino de Bijagual, Colombia

Antecedentes y Objetivos: El bosque altoandino en Colombia corresponde a una formación vegetal, localizada entre 2400-3200(-3500) m s.n.m. Se caracteriza por la presencia de especies arbóreas con distribución restringida que determinan su fisionomía y composición. No obstante, dichas especies han sido afectadas por la actividad agrícola que ha generado pérdida de conectividad y de riqueza. Esta investigación registra la riqueza, composición y datos de distribución de flora vascular en el bosque altoandino del Macizo de Bijagual, Boyacá, Colombia. Métodos: Se realizaron muestreos en 27 transectos. Los ejemplares fueron organizados bajo el sistema de clasificación APG IV, curados y depositados en el herbario UPTC (Universidad Pedagógica y Tecnológica de Colombia). Se obtuvo el número de especies, listado de taxa, distribución para Colombia y categorías de conservación según la UICN. Resultados: Se registraron 327 especies, distribuidas en 151 géneros y 69 familias; 187 especies (56%) son nativas de la región andina, 51 (15%) endémicas de los Andes y 24 (7%) endémicas de la cordillera Oriental colombiana. Schefflera bejucosa es un nuevo registro de distribución para Boyacá. Greigia stenolepis, Hieronyma rufa, Puya goudotiana y Tillandsia pallescens presentan la categoría Casi Amenazado (NT), Plutarchia guascensis, Quercus humboldtii y Symplocos venulosa, Vulnerable (VU); Diplostephium oblongifolium y Dunalia trianaei En Peligro (EN). Conclusiones: Bijagual es un corredor biológico con gran potencial de biodiversidad comparado con otras áreas altoandinas en Colombia. La riqueza es influenciada por otras localidades cercanas al Macizo (Tota y Mampacha), además de una posible distribución estocástica y heterogénea entre unidades de muestreo. Miconia, Pentacalia, Epidendrum, Elaphoglossum, Tillandsia y algunos otros géneros son ricos en especies. Clusia alata, Weinmannia balbisiana, Weinmannia rollottii, Ternstroemia cf. camelliifolia y Brunellia comocladifolia definen la fisionomia arbórea y arbustiva de Bijagual.

Rasgos funcionales de la especie invasora Thunbergia alata (Acanthaceae) y su importancia en la adaptación a bosques andinos

Antecedentes y Objetivos: Thunbergia alata es una de las diez especies de plantas invasoras más problemáticas de Colombia. Su rápida colonización y adaptación a los bosques andinos ha afectado la composición y estructura de las comunidades vegetales nativas. En esta investigación se realizó un análisis de rasgos funcionales, generando nueva información que podría explicar la rápida colonización, adaptación y potencial invasor de T. alata en este tipo de ambientes andinos. Métodos: Para obtener esta información se realizó una serie de observaciones sobre la morfología y anatomía de raíces, tallos, hojas, flores, frutos y semillas. Asimismo, se realizó una caracterización de sus visitantes florales y de las relaciones simbióticas con los microorganismos del suelo. Resultados clave: Se determinó que tanto los rasgos morfológicos como los fenómenos de interacción favorecen la adaptabilidad de T. alata en los bosques andinos y podrían contribuir en mayor medida a su colonización activa en este tipo de ambientes. Se encontró una asociación activa de T. alata con diferentes especies de visitantes florales nativos e introducidos, con un total de 2266 visitas florales realizadas durante nuestro estudio por siete especies de insectos pertenecientes a los órdenes Coleoptera e Hymenoptera. En todos los sitios de muestreo se encontraron esporas de hongos micorrizógenos asociadas a las poblaciones de T. alata. El número de esporas por 100 g de suelo variaba entre 300 y 424. Todas las raíces de T. alata, sin excepción, presentaban una alta colonización por hongos micorrizógenos arbusculares. Conclusiones: Creemos que la información obtenida en esta investigación contribuirá a la generación de estrategias integrales y efectivas para el control de esta especie en los bosques andinos.

Diversity of ground‐dwelling ants across three severely threatened South American subtropical forests: are diversity patterns influenced by spatial or climatic variables?

Abstract Understanding the spatial distribution of species sheds light on the biogeographical history, offers clues to the drivers of biodiversity and helps guide conservation strategies. In southern South America, Andean, Chaco and Atlantic forests drastically decreased their coverage in the last decades mainly by changes in land use. Ants represent an excellent model for macro‐ecological studies that support evidence‐based management policies. Unfortunately, little is known about ant distribution, diversity patterns and drivers in the southernmost portion of these three biomes. We surveyed ground‐dwelling ants using baits and leaf‐litter sieves in 38 sites across these subtropical forests in Argentina. We analysed ant species richness, turnover and composition within and between forests, and whether spatial and climatic variables explain diversity patterns. We collected 161 species belonging to 38 genera. The Atlantic forest had the highest cumulative species richness (91 species), followed by the Chaco (60) and Andean (52) forests. Neither mean species richness nor beta diversity differed significantly between forests, though both indicators tended to increase from west to east. Seven spatial and climatic variables differentiated forests. Aridity index, and variables associated with seasonal rainfall, moderately influenced a tendency to increase species richness from west to east. We identified five shared species between the Andean and Atlantic forests, which are candidates to test biogeographic hypotheses. The high level of species replacement across and among forests resulted in unique assemblages (with at least 29 species that seem to be exclusive to one forest), indicating the importance of conserving the biodiversity of the three forests.

Plant Trait Assembly in Species-Rich Forests at Varying Elevations in the Northwest Andes of Colombia

Andean forests are home to a strikingly high diversity of plants, making it difficult to understand the main drivers of species assembly. Trait-based approaches, however, help overcome some challenges associated with high taxonomic complexity, providing insights into the main drivers of species coexistence. Here, we evaluated the roles of climate, soil fertility, and symbiotic root associations on shaping the assembly of six plant functional traits (leaf area, specific leaf area, dry leaf matter content, leaf thickness, leaf toughness, and wood density) along an elevational gradient in the species-rich northwestern Andean forests of Colombia. The two main axes of the correspondence RLQ analysis explained 95.75% of the variability. The first axis was associated with the leaf economic spectrum, while the second axis with the tradeoff between growth and survival. Furthermore, the fourth corner method showed that both regional (climatic variables) and local factors (soil fertility, symbiotic root associations, and light distribution) played a key role in determining plant trait assembly. In summary, our study emphasizes the importance of considering both individual size and local factors to better understand drivers of plant trait assembly along environmental gradients.

A NEW SPECIES OF DICHAEA (ORCHIDACEAE: ZYGOPETALINAE) FROM THE ANDES OF COLOMBIA

A new species of Dichaea sect. Dichaea from the Andean forests in Colombia is described and illustrated based on living material. Dichaea andina is compared with the morphologically similar D. lagotis and D. pendula, from which it can be distinguished by a number of vegetative and floral and features. Dichaea andina differs from D. lagotis in the broadly anchoriform lip, the hypochile transversely subrounded and the epichile transversely narrowly elliptic, briefly apiculate. Similarly, it differs from D. pendula in the caespitose habit, the leaves without cross-venation, and the inflorescence straight produced below the foliage, among other features. Ecological information for the new species is also provided.

A new species and palinotaxonomy of Besleria (Gesneriaceae) from the cloud forest of Valle del Cauca, Colombia

We describe and illustrate a new species of Besleria (Gesneriaceae) from the department of Valle del Cauca, Colombia. This new species is morphologically similar to B. florida, B. microphylla, B. silverstoneana, and B. solanoides. We include a morphological key to distinguish B. brevisepala from similar species. We also studied pollen morphology to provide support for taxonomic differences among Besleria species from the Andean forest of Colombia. We investigated the pollen characteristics of the genus and assessed their use for taxonomic differentiation in this group through light and electron microscopy. Pollen grains were subjected to acetolysis, measured, photographed, and described qualitatively. We analyzed qualitative and quantitative data using descriptive and multivariate statistics. The pollen grains of Besleria were monad, isopolar, small, with circular amb; oblate to suboblate, 3-porate, with circular to oval pores, without annulus, operculate, and with vestibulum. The exine was tectate, perforate, and microreticulate with narrow muri and small lumina of slightly different shape and dimension. Our results confirm that Besleria is a eurypalynous genus, which allowed the identification of pollen morphological characteristics that are important for species differentiation.

Tree community composition, structure and diversity along an elevational gradient in an Andean forest of Northern Ecuador

Tree community composition, structure and diversity along an elevational gradient in an Andean forest of Northern Ecuador

Reflexiones sobre las perspectivas de sostenibilidad ambiental e institucional para la planeación territorial de los sistemas socioecológicos de páramo y bosque altoandino en Colombia

Los sistemas socioecológicos (SSE) de páramo y bosque altoandino en Colombia son sistemas ecológicos que se caracterizan por sus particularidades de estructura, composición y funcionamiento. Son espacios que se han desarrollado como parte de procesos históricos de relación entre los humanos y la naturaleza, lo cual ha determinado lo que son al día de hoy. Este artículo realiza un análisis de las perspectivas y discursos producidos desde los gobiernos y las políticas públicas en torno a la sostenibilidad ambiental, la institucionalidad y la planeación territorial que se emplean para gestionar los territorios con presencia de estos socioecosistemas.

A preliminary review of Nephelomys albigularis (Tomes, 1860) (Rodentia: Cricetidae), with the description of a new species from the Peruvian montane forests.

Nephelomys albigularis is a sigmodontine rodent of the tribe Oryzomyini distributed in the Andean forests from central Ecuador to central Peru. Although several studies recognize this species as monotypic, significant morphological variation has been reported in Peruvian populations that were not properly assessed by direct comparisons with the type series from central Ecuador. We present a preliminary review of N. albigularis with an integrative approach and emphasis on Peruvian populations. We analyzed specimens using morphological and morphometric methods, complemented with phylogenetic analyses and species delimitation using sequence data from the cytochrome-b gene. Our results reveal that N. albigularis (sensu lato) comprises two taxa: N. albigularis s.s., from the montane forests in central and southern Ecuador and northwestern Peru, and Nephelomys sp. nov. from montane forest east of the Maran River. These taxa are morphologically distinct and are separated by a genetic distance of 5.90 1.01%. Nephelomys sp. nov. differs from N. albigularis s.s. by longer rump hairs, narrow hypothenar pads, faintly bicolor tail; absent interorbital ridges, low zygomatic plates, smoothly squared posterior margin of the hard palate or with a small median postpalatal process, smoothly edged ventral margin of the external auditory meatus, and slightly angular mandibular sigmoid notches. In this work, we present a diagnosis and description of the new species of Nephelomys and discuss the role of the Maran River as a potential driver for speciation in the genus Nephelomys.

Evolutionary Diversity Peaks at Mid-Elevations Along an Amazon-to-Andes Elevation Gradient

Elevation gradients present enigmatic diversity patterns, with trends often dependent on the dimension of diversity considered. However, focus is often on patterns of taxonomic diversity and interactions between diversity gradients and evolutionary factors, such as lineage age, are poorly understood. We combine forest census data with a genus level phylogeny representing tree ferns, gymnosperms, angiosperms, and an evolutionary depth of 382 million years, to investigate taxonomic and evolutionary diversity patterns across a long tropical montane forest elevation gradient on the Amazonian flank of the Peruvian Andes. We find that evolutionary diversity peaks at mid-elevations and contrasts with taxonomic richness, which is invariant from low to mid-elevation, but then decreases with elevation. We suggest that this trend interacts with variation in the evolutionary ages of lineages across elevation, with contrasting distribution trends between younger and older lineages. For example, while 53% of young lineages (originated by 10 million years ago) occur only below ∼1,750 m asl, just 13% of old lineages (originated by 110 million years ago) are restricted to below ∼1,750 m asl. Overall our results support an Environmental Crossroads hypothesis, whereby a mid-gradient mingling of distinct floras creates an evolutionary diversity in mid-elevation Andean forests that rivals that of the Amazonian lowlands.

Maqui (Aristotelia chilensis [Mol.] Stuntz) morphological and phenolic traits associated with forests type and latitudinal gradient in natural populations of Patagonia Argentina

Maqui (Aristotelia chilensis [Mol.] Stuntz) is a native berry of the Patagonia Andean forests, which has one of the highest antioxidant levels currently known. This biochemical characteristic strongly depends on the phenolic profile and is highly influenced by the growing environment. The objective of this study was to characterize natural maqui populations in the immediate lee (Argentina) of the Northern Patagonian Andes, distributed in a latitudinal gradient and associated with coihue (Nothofagus dombeyi) and cypress (Austrocedrus chilensis) forests, humid and xeric environments, respectively. Twenty-five natural populations that spanned the geographical distribution of the species in Argentina, were identified. The sites were associated with two forests (coihue and cypress) and three latitudinal groups (north, center and south). Canopy cover and light interception were measured in the selected sites, as well as plant morphology, fruit yield components, phenolic profiles and oxygen radical absorbance capacity (ORAC) of mature berries. Maqui populations associated to cypress are exposed to greater incident total solar radiation and lesser rainfalls, and showed shorter plants with several main stems, multiple branching and smaller specific leaf area (SLA) as compared to those of coihue forest. Maqui populations associated to coihue presented an increase in the number of berries per bunch, and also in the accumulation of phenols and ORAC. The evaluation of the acclimation responses of the natural populations by different environments can contribute to the development of high-yield and quality maqui crops as source of bioactive compounds.

Diet of Hoffmann’s two-toed sloth (Choloepus hoffmanni) in Andean forest

Abstract The Hoffmann’s two-toed sloth (Choloepus hoffmanni) is a species which could potentially be evaluated as threatened, but data on its natural history in wild conditions are still insufficient. The diet in wildlife of C. hoffmanni was studied through of microhistological analysis of indigestible fragments of leaves found in 43 feces samples collected of the 47 samples found in an Andean forest reserve south of Bogotá, Colombia. Four samples were highly decomposed and were not collected. A reference collection was made of 29 tree species where the feces were found or two-toed sloth were observed, to compare with the plant fragments found in the feces. Seventeen species and six fragments of foliar epidermis of undetermined species were identified in sloth diet. Based on this analysis, C. hoffmanni is a generalist folivore, ingesting a wide variety of plant leaves. Based on frequency of occurrence, relative frequency, and percent cover by volume, Brunellia sibundoya, Cordia cylindrostachya, Citharexylum sp., Quercus humboldtii, and Clethra fagifolia made up most (74%) of the diet of C. hoffmanni in an Andean forest. Comparing the plant species found in the feces with the reference collection, C. hoffmanni appears to deposit feces at the base of the trees that it consumes.

Managing environmental diversity in the eastern foothills of the Andes: pre-Columbian agrarian landscapes in the El Alto-Ancasti mountain range

ABTRACT In this paper we review the growing evidence of anthropogenic landscapespresent in the semi-deciduous neotropical forest biomes of eastern NW Argentina,which have remained relatively neglected in favour of arid to semi-arid western Andean regions. The evidence gathered in de El Alto-Ancasti provides animportant case study where multidisciplinary methodologies have beenapplied to sites that document the emergence and variability in food productionstrategies across the eastern Andean forests and grasslands of NWArgentina. We discuss evidence offarming structures from archaeological surveys, plant management from phy-tolith analysis, and the tempo and nature of settlement from archaeological excavations undertaken at a variety of sites in the El Alto Ancasti mountainrange. We suggest that the communities that inhabited this region during thefirst millennium AD (ca. 1500–1000 BP) established a strategy of ‘overlappingpatchworks’ of food production that were able to contend with considerableseasonal variability. We argue that, through the use of cross-channelling, low river areas, erosion control techniques and the establishment of mesothermal crops,including maize, legumes, and tubers, throughout the region, these societies adopted flexible strategies to adapt to life in a region prone to climatic change

Genetic variation in neotropical butterflies is associated with sampling scale, species distributions, and historical forest dynamics.

Previous studies of butterfly diversification in the Neotropics have focused on Amazonia and the tropical Andes, while southern regions of the continent have received little attention. To address the gap in knowledge about the Lepidoptera of temperate South America, we analysed over 3000specimens representing nearly 500species from Argentina for a segment of the mitochondrial cytochrome c oxidase subunit I (COI) gene. Representing 42% of the country's butterfly fauna, collections targeted species from the Atlantic and Andean forests, and biodiversity hotspots that were previously connected but are now isolated. We assessed COI effectiveness for species discrimination and identification and how its performance was affected by geographic distances and taxon coverage. COI data also allowed to study patterns of genetic variation across Argentina, particularly between populations in the Atlantic and Andean forests. Our results show that COI discriminates species well, but that identification success is reduced on average by ~20% as spatial and taxonomic coverage rises. We also found that levels of genetic variation are associated with species' spatial distribution type, a pattern which might reflect differences in their dispersal and colonization abilities. In particular, intraspecific distance between populations in the Atlantic and Andean forests was significantly higher in species with disjunct distributions than in those with a continuous range. All splits between lineages in these forests dated to the Pleistocene, but divergence dates varied considerably, suggesting that historical connections between the Atlantic and Andean forests have differentially affected their shared butterfly fauna. Our study supports the fact that large-scale assessments of mitochondrial DNA variation are a powerful tool for evolutionary studies.

Two new species of Astrothelium (Trypetheliaceae) with amyloid ascospores inhabiting the canopy of Quercus humboldtii trees in Colombia

Subandine and high Andean forests are often dominated by oak trees and these are recognized as suitable phorophytes for diverse epiphyte communities. Among the latter, lichens in the upper strata appear to be understudied. Here, we report the discovery of two new species of Astrothelium (Trypetheliaceae), a diverse genus of tropical crustose lichens, both with the unusual feature of muriform, amyloid ascospores. Astrothelium mordonialensis is characterized by an olive-green thallus with solitary ascomata producing muriform and amyloid ascospores with tightened center and A. rogitamae by a light brownish to greenish grey thallus with yellow pigmented solitary ascomata, producing muriform and amyloid ascospores.