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We describe Elaphoglossum auralolitae, a new species from southwestern Guatemala. The new species belongs to the Elaphoglossum petiolatum complex, in Elaphoglossum section Lepidoglossa, one of the largest sections within the genus. Elaphoglossum auralolitae is characterized by petioles and laminae densely scaly, with large scales including those of costae and margins; the presence of resinous dots on the petioles (mostly obscured by the scales) and on the abaxial laminar surface; and spores with spiny perispores. Only a dozen collections are known of this species so far, all of them from the Sierra Madre mountains in southwestern Guatemala. The first collection of this species was made in 1938 and the most recent was in 1992. We provide a description, taxonomic comments, geographic distribution, phenology, and illustrations for this new species. Describimos Elaphoglossum auralolitae, una especie nueva del suroeste de Guatemala. Esta especie forma parte del complejo de Elaphoglossum petiolatum, el cual hace parte de Elaphoglossum sección Lepidoglossa, una de las secciones más grandes dentro del género. Elaphoglossum auralolitae se caracteriza por pecíolos y láminas densamente escamosos, con escamas grandes, incluyendo las de la costa y las márgenes; presencia de puntos resinosos en los pecíolos (generalmente cubiertos por las escamas) y en la superficie laminar abaxial, y esporas con perisporas espinosas. Hasta el momento se conocen únicamente una docena de colecciones de esta especie, todas provenientes de la Sierra Madre en Guatemala. La primera colecta se realizó en 1938 y la más reciente en 1992. Este trabajo incluye la descripción e ilustración de esta nueva especie, imágenes de sus esporas, comentarios taxonómicos, distribución geográfica y fenología. [ABSTRACT FROM AUTHOR]

Coffee is one of the most important agricultural commodities of Mexico. Mapping coffee land cover is still a challenge because it is grown mainly on small areas in agroforestry systems (AFS), which are located in hard-to-access mountainous regions. The objective of this research was to map coffee AFS types in a mountainous region using the changing spectral response patterns over the dry season as well as supplementary data. We employed Sentinel-1, Sentinel-2 and ALOS-Palsar images, a digital elevation model, soil moisture layers, and 150 field plots. First, we defined three coffee AFS types based on their structural and spectral characteristics. Then, we performed a recursive feature elimination analysis to identify the most relevant predictor variables for each land use/cover class in the region. Next, we constructed a predictor variable dataset for each AFS type and one for the remaining land use/cover classes. Afterward, four maps were generated using a random forest (RF) classifier. Finally, we combined the four maps into a unique land-cover map through a maximum likelihood algorithm. Using a validation sample of 932 sites derived from Planet images (4.5 m pixel size), we estimated a 95% map overall accuracy. Two AFS types were classified as having low error; the third, with the highest tree density, had the lowest accuracy. The results obtained show that the infrared and near-infrared bands from the Sentinel-2 scenes are particularly useful for coffee AFS discrimination. However, supplementary data are required to improve the performance of the classifier. Our findings also highlight the importance of the multi-temporal and multi-dataset approach for identifying complex production systems in areas of high topographic heterogeneity. [ABSTRACT FROM AUTHOR]

Background: Forestry management modifies the diversity, structure, and functioning of intervened forests. Timber extraction reduces tree density and basal area, leading to changes in the communities of vascular epiphytes. The objective of this study was to evaluate the diversity and biomass of vascular epiphytes in Quercus trees remaining in two pine-oak forest stands that have been subjected to two stages of the Silvicultural Development Method (release cutting, and thinning) in comparison with an unharvested old-secondary forest in southern Mexico. For each treatment, richness of epiphytes present on 60 oak trees was recorded and their dry biomass estimated. We calculated the true diversity (Hill numbers) and beta diversity using the Jaccard coefficient of similarity, and generated rank abundance curves per taxonomic epiphyte group (bromeliads, orchids, ferns and others). For each treatment, the relationships between overall diversity and epiphyte biomass to the host trees basal area were analyzed using log linear models. Results: We recorded a total of 67 species of epiphytes species belonging to 10 families hosted by five species of oaks. The greatest species richness (0 D) was recorded in the old-secondary forest. Fewer common (¹ D) and dominant (² D) species were recorded in the release cutting than in the other treatments. Epiphyte diversity and biomass were both slightly related to host tree basal area. Composition of epiphytes was similar (60%) among treatments, although orchids, bromeliads, and other families were more diverse in the old-secondary forest. Most bromeliad species were shared across all treatments, although orchids presented the most exclusive species in the unharvested forest. The bromeliad Tillandsia seleriana provided the greatest contribution to biomass in all treatments, followed by the orchid Camaridium densum. Generalized linear models indicated that epiphyte diversity was significantly related to treatment, and epiphyte biomass to basal area of host trees. Conclusions: Although forest management affects diversity, composition, and abundance of vascular epiphytes, most of their diversity and biomass can be maintained despite timber harvesting. This requires sparing some mature oaks during logging, as they contribute to conservation, establishment, and development of epiphytic communities, and maintaining untreated areas as a source of propagules for these communities. [ABSTRACT FROM AUTHOR]

Carex section Schiedeanae (subg. Euthyceras) has long been thought to comprise at most five species of Mexican sedges. Our morphological studies in the field and herbarium, however, supported by more recent DNA sequencing work, demonstrate that the section is, in fact, three times as species‐rich, making it one of the largest sections in Mexico. Its 15 species range from Chihuahua to Tamaulipas south to Veracruz and Oaxaca; a single species, Carex muriculata, extends into the United States. The section has unusual inflorescences with simple (except in Carex complexa), uniformly androgynous, sessile spikes, utriculiform cladoprophylls, and perigynia with a unique combination of pubescence types composed of papillae; unicellular, simple hairs; and (in many species) multicellular tubercles. We recognize five previously described species (C. muriculata, Carex perstricta, Carex schiedeana, Carex stellata, and Carex vizarronensis) and describe 10 additional species (Carex angustilepis, Carex cabralii, Carex complexa, Carex dentata, Carex gypsophila, Carex mesophila, Carex paneroi, Carex planilamina, Carex revoluta, and Carex tehuacana). We have expanded the morphological features used in the section to include particularly anther, staminate scale, and style features, and more detailed micromorphology of the perigynia, especially indumentum. In total, 13 of the 15 species recognized herein, with a total of 32 individuals, were examined for ETS and ITS for phylogenetic reconstruction. Phylogenetically, the xeric species (plus C. paneroi) form a grade leading to a clade of the more mesophytic species adapted to forest understories, plus the unique cliff dwelling C. complexa. [ABSTRACT FROM AUTHOR]

Laramide deformation during the Late Cretaceous through early Eocene interrupted the east‐flowing drainage systems from the Sevier hinterland and segmented the Western Interior Foreland Basin in much of western North America into a series of intermontane basins and Precambrian basement‐cored uplifts. In Wyoming, the timing of Laramide deformation and its impacts on drainage patterns during the overlap in the Sevier and Laramide orogenies remain under debate. New detrital zircon U‐Pb geochronologic data from 11 outcrop samples (n = 3,085) in south‐central Wyoming suggest at least two provenance‐distribution phases, distinguished by a substantial increase in zircons of late Paleoproterozoic age (1800–1600 Ma) recorded at approximately 79 Ma. The most likely source of late Paleoproterozoic age zircons is Precambrian basement‐cored uplifts, specifically the Sierra Madre Mountains, signaling the possible middle Campanian initiation of Laramide uplift, earlier than previously recorded. When combined with complementary data sets from surrounding basins, the first provenance‐distribution phase is age discordant, with the earliest evidence of 1800–1600 Ma zircons in the Piceance Basin of Colorado (late Santonian to early Campanian). The second provenance phase shows repeating age distribution patterns that begin with significant contributions from 1800 to 1600 Ma zircon grains and end with much broader and evenly distributed population signatures, confirming previous interpretations of significant Laramide deformation during the Maastrichtian (approximately 70 Ma) as well as uplift and recycling of Upper Cretaceous formations at about 67 Ma. Plain Language Summary: During the Late Cretaceous, Wyoming was part of an epicontinental seaway that extended from Canada to Mexico. This Western Interior Seaway was a low spot in the North American continent formed from mountain building and crustal loading of the Wyoming fold‐and‐thrust belt to the west, an event known as the Sevier orogeny. At some point in the Late Cretaceous, an event known as the Laramide orogeny segmented the Western Interior Foreland Basin into a series of intermontane basins by basement‐cored uplifts that are today's mountain ranges. The timing of the Laramide orogeny, and its impacts on the east‐flowing drainage systems from the Sevier hinterland, has been the subject of research and argument for more than a century. New age data obtained from zircons preserved in outcrop samples collected in south‐central Wyoming—showing unique zircon populations that were most likely derived from the basement core of nearby mountain ranges—suggest at least two episodes of Laramide uplift in the Upper Cretaceous through Paleocene strata. The first event occurred about 79 million years ago, earlier than previously recorded in Wyoming. The second event recurred approximately 67 million years ago, coincident with the main phase of Laramide deformation recorded throughout much of Wyoming. Key Points: Geochronologic data from Upper Cretaceous and Paleocene strata in Wyoming record a substantial increase in late Paleoproterozoic age zirconsThese zircons suggest exhumation of the Sierra Madre Mountains, implying Laramide uplift at about 79 Ma, earlier than previously documentedRepeated pulses of Paleoproterozoic age zircons indicate renewed uplift at 67 Ma, coincident with the primary phase of Laramide deformation [ABSTRACT FROM AUTHOR]

• Wyoming and Superior cratons were adjacent in the early Paleoproterozoic. • ca. 2.45 Ga Large Igneous Province (LIP) Event impacted both cratons. • Several rifting events are recorded on both cratons. • Cratons started to separate at ca. 2.09 Ga and broke up at ca. 2.07 Ga. • A block/sliver bridging these two cratons is inferred. Paleogeography is critical as a backdrop for environmental changes, yet the Paleoproterozoic configuration of Archean cratons remains controversial. The Snowy Pass Supergroup (SPS), a Paleoproterozoic succession on the SE Wyoming craton (Medicine Bow Mountains, MBM), has been correlated with the Huronian Supergroup (HS) of the Superior craton, suggesting deposition in the same basin, and indicating that these cratons were adjoined in the Paleoproterozoic Superia supercraton. We present U-Pb volcanic and detrital zircon data for the underlying Phantom Lake Metamorphic Suite (PLMS), SPS, and Snowy Pass Group (SPG; Sierra Madre, SM) and U-Pb zircon ages for two mafic sills and Baggot Rocks granite. The PLMS contains a statistically significant mode of ca. 2.45 Ga zircon dates in the SM; zircons of this age also occur in one to two grain quantities in the PLMS in the MBM. The Baggot Rocks granite and Colberg Metavolcanics of the PLMS also yielded the ca. 2.45 Ga U-Pb zircon ages, indicating the early Paleoproterozoic age for this suite and the ca. 2.45 Ga extensive, rift-related mafic magmatism on the southern margin of the Wyoming craton, allowing correlation with the basal HS units of the Superior craton. Zircon age spectra for lithostratigraphically correlative units on the Wyoming and Superior cratons show strikingly similar, primarily Archean patterns, which, along with paleocurrent directions, establish provenance of both cratons for the shared basin; ca. 2.55 and 2.3 Ga modes are common for the uppermost formations. Fine-grained siliciclastic rocks throughout the SPS yield similar T DM and εNd ages as well as μ and κ values to the HS, further supporting similar provenance for the two supergroups. Mafic sills in the MBM yielded U-Pb zircon dates of 2220 ± 8 Ma and 2094.3 ± 1.6 Ma that closely correspond to the age of the Nipissing mafic intrusions in the HS and the Cauchon Lake dikes in the NW Superior craton. Correlation between the HS and SPS breaks down in the upper SPS at the Nash Fork Formation, which bears detrital zircon age modes at ca. 2.2 and 2.1 Ga, whereas deposition of the HS terminated before ca. 2.22 Ga when the Nipissing dikes intruded and shortly after a ca. 2.31 Ga volcanic event recorded by the Gordon Lake and Bar River formations. The matching detrital zircon dates to a globally unique, ca. 2.3 Ga, mode first appeared in the Lookout Schist of the SPS and steadily decreased up-section through the upper SPS, pointing to a similar volcanic source. Maximum depositional ages for the uppermost formations of the SPS and SPG, the purportedly correlative Nash Fork and Slaughterhouse formations, are at 2081 ± 10 Ma and 2334 ± 20 Ma, respectively. The former detrital zircon mode corresponds to that recorded by the basal Animikie basin units (Denham Formation of the Mille Lacs Group in MN and East Branch Arkose of the Dickinson Group, MI) and are linked to rifting, breakup, and ultimate separation of the Wyoming and Superior cratons at ca. 2075 Ma. [ABSTRACT FROM AUTHOR]

The article discusses a study that examined the secretive, frugivorous forest monitor lizard, Varanus which was discovered in the forests of the northern Philippines. Data from morphology and mitochrondrial and nuclear DNA sequences were discussed. Some of the unique characteristics of Varanus bitatawa are robust body, anteriorly directed and contrasting black and golden yellow dorsal coloration. The study analyzed the geographical gap between Varanus bitatawa and Varanus olivaceus.

The study of four species of birds of genus Passerina in the Biosphere Reserve La Sepultura, Chiapas, Mexico was carried out. The objective was to know the occurrence places and to estimate their distribution and abundance. The search consisted on carrying out the summary of current and historical records in databases and the sampling in six sites that were visited during January to December of 1999. All records were assigned to a coordinate system, being also digiized the distribution of types of vegetation and the gradient altitudinal of the study of area. By means of analysis of averlaps of these coverings and the reported ecological tolerances and observed for the species, three maps were generated: one of the occurrence of the four species and other two on the areas of potential distribution, for the species residents. The relative abundance was obtained by season (dry and humid) for each one of the species of the genus, with relationship to the sampling effort and expressed in percentage for each site. The results of abundance were analyzed by the statistical test of G. The sites of occurrence of the species of the genus are in five municipalities in those that the Reserve is located. The resident species are restricted to the distribution of Tropical Semi-Deciduous Forest. The migratory species presented a wide distribution range, being able to inhabit pine forest, pine-oak forest and cloud forests. The abundance of the species of the genus, it was greater in the nearby region to the Isthmus of Tehuantepec. [ABSTRACT FROM AUTHOR]

The trout of northwest Mexico represent an undescribed group of fish considered part of the Oncorhynchus mykiss (Pacific trout) complex of species and subspecies. Recent genetic studies have shown these fish to have important genetic diversity and a unique evolutionary history when compared to coastal rainbow trout. Increased levels of allelic diversity have been found in this species at the southern extent of its range. In this study we describe the trout in the Sierra Madre Occidental from the rios Yaqui, Mayo, Casas Grandes and de Bavispe, and their relationship to the more southern distribution of Mexican golden trout ( O. chrysogaster) using 11 microsatellite loci. Microsatellite allelic diversity in Mexican trout was high with a mean of 6.6 alleles/locus, average heterozygosity = 0.35, and a mean Fst = 0.43 for all loci combined. Microsatellite data were congruent with previously published mtDNA results showing unique panmictic population structure in the Rio Yaqui trout that differs from Pacific coastal trout and Mexican golden trout. These data also add support for the theory of headwaters transfer of trout across the Continental Divide from tributaries of the Rio de Bavispe into the Rio Casas Grandes. Rio Mayo trout share a close genetic relationship to trout in Rio Yaqui, but sample sizes from the Rio Mayo prevent significant comparisons in this study. Microsatellite analyses show significant allelic frequency differences between Rio Yaqui trout and O. chrysogaster in Sinaloa and Durango Mexico, adding further support for a unique evolutionary status for this group of northwestern Mexican trout. [ABSTRACT FROM AUTHOR]