A biogeographic regionalisation of the Neotropical region is proposed as a hierarchical classification of sub-regions, dominions, provinces and districts. This regionalisation is based on biogeographic analyses of terrestrial plant and animal taxa, and seeks to provide universality, objectivity and stability, such that it can be applied when describing distributional areas of particular taxa or comparing different biogeographic analyses. The Neotropical region is currently comprised of three sub-regions (Antillean, Brazilian and Chacoan), two transition zones (Mexican and South American), seven dominions (Mesoamerican, Pacific, Boreal Brazilian, Southwestern Amazonian, Southeastern Amazonian, Chacoan and Parana) and 53 provinces. For some of the latter, sub-provinces and districts are recognized. Complete synonymies and brief descriptions of the areas are provided, as well as the endemic taxa that diagnose the different provinces.

/pdf/biogeographical-regionalisation-of-the-neotropical-region-2mev0mnuco.pdf

Biogeographical regionalisation of the Neotropical region

Track and cladistic biogeographic analyses based on insect taxa are used as a framework to interpret patterns of the Latin American and Caribbean entomofauna by identifying biogeographic areas on the basis of endemicity and arranging them hierarchically in a system of regions, subregions, dominions, and provinces. The Nearctic region, inhabited by Holarctic insect taxa, comprises five provinces: California, Baja California, Sonora, Mexican Plateau, and Tamaulipas. The Mexican transition zone comprises five provinces: Sierra Madre Occidental, Sierra Madre Oriental, Transmexican Volcanic Belt, Balsas Basin, and Sierra Madre del Sur. The Neotropical region, which harbors many insect taxa with close relatives in the tropical areas of the Old World, comprises four subregions: Caribbean, Amazonian, Chacoan, and Parana. The South American transition zone comprises five provinces: North Andean Paramo, Coastal Peruvian Desert, Puna, Atacama, Prepuna, and Monte. The Andean region, which harbors insect taxa with close relatives in the Austral continents, comprises three subregions: Central Chilean, Subantarctic, and Patagonian.

http://repositorio.fciencias.unam.mx:8080/xmlui/bitstream/handle/11154/140629/Morrone_2006_AnnuRevEntomol820.pdf?sequence=1

Biogeographic areas and transition zones of Latin America and the Caribbean islands based on panbiogeographic and cladistic analyses of the entomofauna.

1. The study of plant-pollinator interactions in a network context is receiving increasing attention. This approach has helped to identify several emerging network patterns such as nestedness and modularity. However, most studies are based only on qualitative information, and some ecosystems, such as deserts and tropical forests, are underrepresented in these data sets. 2. We present an exhaustive analysis of the structure of a 4-year plant-pollinator network from the Monte desert in Argentina using qualitative and quantitative tools. We describe the structure of this network and evaluate sampling completeness using asymptotic species richness estimators. Our goal is to assess the extent to which the realized sampling effort allows for an accurate description of species interactions and to estimate the minimum number of additional censuses required to detect 90% of the interactions. We evaluated completeness of detection of the community-wide pollinator fauna, of the pollinator fauna associated with each plant species and of the plant-pollinator interactions. We also evaluated whether sampling completeness was influenced by plant characteristics, such as flower abundance, flower life span, number of interspecific links (degree) and selectiveness in the identity of their flower visitors, as well as sampling effort. 3. We found that this desert plant-pollinator network has a nested structure and that it exhibits modularity and high network-level generalization. 4. In spite of our high sampling effort, and although we sampled 80% of the pollinator fauna, we recorded only 55% of the interactions. Furthermore, although a 64% increase in sampling effort would suffice to detect 90% of the pollinator species, a fivefold increase in sampling effort would be necessary to detect 90% of the interactions. 5. Detection of interactions was incomplete for most plant species, particularly specialists with a long flowering season and high flower abundance, or generalists with short flowering span and scant flowers. Our results suggest that sampling of a network with the same effort for all plant species is inadequate to sample interactions. 6. Sampling the diversity of interactions is labour intensive, and most plant-pollinator networks published to date are likely to be undersampled. Our analysis allowed estimating the completeness of our sampling, the additional effort needed to detect most interactions and the plant traits that influence the detection of their interactions.

https://besjournals.onlinelibrary.wiley.com/doi/pdf/10.1111/j.1365-2656.2011.01883.x

Evaluating sampling completeness in a desert plant–pollinator network

http://www.asu.edu/clas/sirgtools/pogonomyrmex/species%20photos/pogo%20eremicus/monte%20desert%20biogeography%20plants.pdf

Biogeography of the Monte Desert

We review the status of the four currently recognized guanaco Lama guanicoe subspecies, and provide information about their taxonomy and distribution. The success of guanaco in inhabiting open habitats of South America is based mainly on the flexibility of their social behaviour and ecophysiological adaptations to harsh environments. 2. Lonnberg described the first subspecies, L. g. cacsilensis , at the beginning of the 20th century. Forty years later Krumbiegel described L. g. voglii , based on skull measurements and pelage colouration. The other two subspecies, L. g. huanacus and L. g. guanicoe , were classi- fied as subspecies by Krumbiegel based on pelage colouration and body size, while maintain- ing the original Latin names and descriptors. 3. Further guanaco populations have been incorporated into each of these subspecies, based on their proximity to the type locality but without attention to the homogeneity of phenotype or habitat and only limited consideration of Bergmann's rule based on scarce skulls. Two alternative geographical ranges were proposed in the middle and towards the end of the 20th century. Discrepancies occur in the geographical range of each subspecies. 4. Molecular studies based on mitochondrial DNA cytochrome b sequences recognized only two subspecies: the Peruvian L. guanicoe cacsilensis and the rest of the populations grouped in the clade recognized as L. g. guanicoe . We conclude that the evolutionary biology of L. guanicoe requires a significant revision with respect to biogeography. Phylogeographical data hold particular value in developing conservation strategies, particularly for some of the reduced and marginal populations and/or subspecies and will support IUCN (The World Conservation Union) Red List classification.

/pdf/taxonomic-and-biogeographical-status-of-guanaco-lama-1e3xy4acog.pdf

Silvia Claver

Papers

Monte Desert (Argentina): insect biodiversity and natural areas