Pine-oak Forest Research Articles

Pinus devoniana LIKELY AVOIDS DROUGHT STRESS BY DELAYING SHOOT ELONGATION

Understanding the growth rate and the timing of conifer seedling bud elongation can be useful in selecting tree species for commercial plantations and ecological restoration, either under the current climate or to adapt to climatic change. Shoot growth dynamics of three dominant Pinus species of the pine-oak forest of the Nuevo San Juan Parangaricutiro indigenous community in Western Mexico were inspected. Using a common garden trial of three species and seven provenances, growth was related to contemporary (1961-1990 period averages) and future (rcp6.0 ensemble and decade centered on year 2060) climate. Significant differences between specieswere found in two-year-old plants, P. pseudostrobus and P. leiophylla showed greater shoot elongation and plant height, larger elongation period and plant height, and later growth cessation than P. devoniana, P. pseudostrobus and P. leiophylla, which begin their growth and elongate their shoots during the warm, dry season (March to May). Pinus devoniana delays the start of growth until the end of the dry season (end of May). This suggests that P. devoniana, at least for the second year of growth, probably avoids drought stress by delaying shoot elongation, which could partly explain why this species grows at lower altitude than the other pines. Climate change projections for Mexico indicate an increase in aridity conditions by the year 2060, particularly for the lower altitudinal limit of the populations of P. pseudostrobus and P. leiophylla. Reforestation with P. devoniana might be required at the lower altitud limits of these pines if forest decline continues.

Two new food items in the diet of the Aztec Thrush (Ridgwayia pinicola) and first evidence of florivory

The Aztec Thrush (Ridgwayia pinicola) is an understudied species. Many aspects of its basic biology are unknown, including its food and foraging preferences. Here, we describe observations of Aztec Thrush consuming fruits of the tree Ilex brandegeeana and flowers of the bromeliad Tillandsia bourgaei in the pine-oak forest of the highlands of Jalisco in western Mexico. These observations provide information about the diet of this species and its possible ecological role in regenerating and structuring processes of this forest.

Ericaceous shrub expansion and its relation to fire history in temperate pine-oak (Pinus-Quercus) forests of the eastern U.S.A.

Ericaceous shrub expansion and its relation to fire history in temperate pine-oak (Pinus-Quercus) forests of the eastern U.S.A.

Modelling avocado-driven deforestation in Michoacán, Mexico

As demand for avocado climbs, avocado production in Michoacán—Mexico’s biggest avocado growing region—expands into new places. We use a spatial probit model to project the geographic distribution of likely future avocado expansion and analyze those results to determine (a) threats to specific forest types and (b) how the distribution of avocado is shifting spatially under current and future climate scenarios. Our results suggest that avocado expansion in Michoacán is strongly driven by distance to existing agriculture, roads, and localities, as well as the dwindling availability of Andosol soils. As future expansion ensues, it presents risk of forest loss across various forest types, with pine-oak forest, mesophilic montane forest, and oyamel fir forest being of particular concern. Moreover, our results suggest that avocado production will occupy wider ranges in terms of temperature, precipitation, slope steepness and soil. The model predicts that climate change will alter the spatial distribution of avocado plantings, expanding into forest types at lower and at higher elevations. Forest loss threatens ecosystem degradation, and a wider avocado crop production footprint could lead to orchard establishment into dwindling forests that host a high diversity of native oaks and charismatic species, including the monarch butterfly.

Modelling avocado-driven deforestation in Michoacán, Mexico

Abstract As demand for avocado climbs, avocado production in Michoacán - Mexico’s biggest avocado growing region - expands into new places. We use a spatial probit model to project the geographic distribution of likely future avocado expansion and analyze those results to determine (1) threats to specific forest types and (2) how the distribution of avocado is shifting spatially under current and future climate scenarios. Our results suggest that avocado expansion in Michoacán is strongly driven by distance to existing agriculture, roads, and localities, as well as the dwindling availability of Andosol soils. As future expansion ensues, it presents risk of forest loss across various forest types, with pine-oak forest, mesophilic montane forest, and oyamel fir forest being of particular concern. Moreover, our results suggest that avocado production will occupy wider ranges in terms of temperature, precipitation, slope steepness and soil. The model predicts that climate change will alter the spatial distribution of avocado plantings, expanding into forest types at lower and at higher elevations. Forest loss threatens ecosystem degradation, and a wider avocado crop production footprint could lead to orchard establishment into dwindling forests that host a high diversity of native oaks and charismatic species, including the monarch butterfly.

Extinction of endemic taxa as a direct consequence of global climate change

Global climate change occurs from both natural and anthropic causes. Anthropic climate change has effects at various scales and occurs faster than the adaptation of species to these changes. Protected natural areas have been created to preserve species from the different threats facing them. Sierra La Laguna is a sky island with almost no anthropic pressure given its natural isolation; it is home to several endemic taxa, including Peromyscus truei lagunae and Sorex ornatus lagunae. This study aims to assess the possible impact of climate change on species endemic to a sky island exposed to virtually no local anthropic pressure. The Sierra La Laguna sky island, located in the southern region of the Baja California peninsula, harbors different vegetation types, including an oak-pine forest at the highest elevations and xeric vegetation at lower ones. Ecological niche models were developed under three climate change scenarios contemplating temperature rises of 1.5 °C and 4.4 °C. There are insufficient localities to make statistically robust models for mammalian species. Therefore, we used plant species typical of the oak-pine forest (Pinus cembroides lagunae, Quercus brandegeei, and Q. devia) and the rodents Peromyscus eva, that thrives in dry deciduous forests, and Chaetodipus rudinoris and C. spinatus, associated with xeric ecosystems. The models show that ecological suitability for the oak species decreases, while it is completely lost for the pine species. On the other hand, P. eva broadens its elevational range, while C. rudinoris and C. spinatus increase their ecological suitability in both area and elevation. The Sierra La Laguna sky island is an area with virtually no regional or local anthropic pressure. Nonetheless, the projections conducted under various climate change scenarios show a loss of up to 100 % of the area of climatic and elevational suitability for species characteristic of the oak-pine forest even with the minimum temperature rise of 1.5 °C. These results suggest that, under these conditions, endemic species such as P. t. lagunae and S. o. lagunae will become extinguished despite the absence of local anthropic pressures.

Increased survival rate of Quercus aliena var. Acuteserrata seedlings via nitrogen addition for the succession of pine and pine-oak mixed forests to oak forest

Forest regeneration mechanisms of Pinus tabulaeformis, Pinus armandii, and Quercus aliena var. acuteserrata as the constructive species have been the focus of ecologists and silviculturists, and research to better understand the future of forest community composition, succession patterns, and other aspects of far-reaching influence. However, the influence of nitrogen deposition on the regeneration of different succession stages needs further investigation. In this study, seedlings of the three species of different ages were planted in the pine, pine-oak mixed, and oak forests, and the seedlings which planted by the pot culture with natural soil or fertilization soil, were monitored for two years. Survival and growth indicators, chlorophyll content, and foliar nutritional status of the seedlings were measured. The survival rate and chlorophyll content of P. tabulaeformis, P. armandii, and Q. aliena var. acuteserrata seedlings were the lowest in the oak forest, which might be related to the availability of light in the undergrowth at different stages of succession. Regardless of the forest type, after nitrogen addition, the survival rates of P. tabulaeformis and Q. aliena var. acuteserrata seedlings were the highest for 4-year-old seedlings, and the survival rate of P. armandii seedlings was the highest for 10-year-old ones. Nitrogen addition had no significant effect on the survival rate of P. tabulaeformis and P. armandii seedlings, but changed the nutrient content in their leaves. However, the addition of nitrogen improved the survival rate of Q. aliena var. acuteserrata seedlings, and their competitiveness. Therefore, it can be inferred that nitrogen deposition may promote the succession of P. tabulaeformis forest- to oak forest-in the Qinling Mountains, China.

Systematic study and niche differentiation of the genus Aporocactus (Hylocereeae, Cactoideae, Cactaceae)

Background: Aporocactus is an epiphytic or saxicolous genus that is endemic to Mexico and has a distribution restricted to cloud forests and pine-oak forests. As with many cacti, Aporocactus presents taxonomic conflicts, especially regarding species delimitation, since five species in this genus have been described and accepted by some authors, while others accept only two species.
 Questions: How many species comprise Aporocactus? What are their relationships? Do these species show differences in their climatic preferences?
 Studied species: The five putative species in Aporocactus were investigated.
 Study site and dates: This study was conducted in 2015 and 2016. The collection sites were in Hidalgo, Puebla, Querétaro, Veracruz, and Oaxaca states, Mexico.
 Methods: In this study, phylogenetic analyses were performed using chloroplast DNA markers from different Aporocactus populations and related genera, and ecological niche modeling techniques were also employed.
 Results: The phylogenetic analyses indicated that Aporocactus is composed of only two species: A. flagelliformis and A. martianus . Additionally, the phylogenetic analyses corroborated that Aporocactus is an early diverging group related to Weberocereus and Selenicereus . Finally, niche modeling and niche identity testing indicated that the niches of the two species of Aporocactus are significantly differentiated and niches are more different than would be expected by chance.
 Conclusions: Despite being a genus with only two species, Aporocactus represents a useful model for investigating such topics as the ecology of pollination, genetic populations, and flower development to characterize the evolution of these specialized cacti.

Importance of Quercus spp. for diversity and biomass of vascular epiphytes in a managed pine-oak forest in Southern Mexico

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. We recorded a total of 67 species of epiphytes species belonging to 10 families hosted by five species of oaks. The greatest species richness (0D) was recorded in the old-secondary forest. Fewer common (1D) and dominant (2D) 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. 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.

Habitat of the Long-Tailed Wood-Partridge in Central Mexico

The long-tailed wood-partridge (Dendrortyx macroura; hereafter, wood-partridge) is a forest quail endemic to the temperate forests of the Trans-Mexican Volcanic Belt of central Mexico and is considered threatened according to the Secretariat of the Environment of Mexico. We studied 34 sites within the Natural Resources Protection Area River Basins of the Valle de Bravo, Malacatepec, Tilostoc and Temascaltepec in central Mexico to evaluate wood-partridge habitat during September–December 2019. We evaluated attributes of tree, shrub, and herbaceous vegetation, canopy cover, humidity, slope, and altitude. We also identified vegetation used for nesting, food, and shelter. The scant information published for other geographical areas indicates habitat consists of pine (Pinus spp.), pine-oak (Quercus spp.), and cloud forest. We found that the preferred habitat in the Trans-Mexican Volcanic Belt was forest dominated by Alnus firmifolia, Pinus patula, Pinus pseudostrobus, Pinus teocote, and Quercus castanea. Wood-partridge preferred sites with an average of 90% canopy coverage, 100% shrub cover, high percent humidity, slopes >30%, and altitudes that ranged 2,700–3,000 meters above sea level. Additionally, we located an inactive nest in an area with 100% shrub cover and 80% tree cover in forest dominated by Pinus patula, relative humidity of 55%, and a temperature of 19° C. This is the first investigation of this bird within this important biogeographic transition zone between the Nearctic region and the Neotropics. We report the basic characteristics of the habitat used by this species along with the first description of a nest in an area with high rates of deforestation, overgrazing, and forest fires. The “gallinita de monte” represents an important element of the biocultural heritage for the Mazahua and Otomí peoples, who are Indigenous inhabitants of this area. We recommend additional research on wood-partridge to determine the extent of poaching and collection of eggs for food; determine effects of forest management; determine its basic ecology including survival, reproduction, and population density; verify habitat relationship; and corroborate information that describes the traditional knowledge of the species by the native Mazahua and Otomí peoples. We suggest it is most important to learn more about and disseminate traditional knowledge of the species and to preserve its biocultural value and heritage, particularly for Indigenous communities.

Карта растительности ключевого участка Амуро-Зейского междуречья

In 1965 T. I. Isachenko made a scheme of geobotanical zoning for the southern part of the Amur-Zeya interfluve. She identified five geobotanical districts and subdistricts within the boundaries of zones and subzones. This zoning stays relevant to the present day. V. V. Lipatova (1969а) created the large-scale geobotanical maps of key areas for the Amur and Central districts. No other work on vegetation mapping in the Amur-Zeya interfluve was done for this area. The research goal is to make a large-scale vegetation map of the study area showing the current state and diversity of the vegetation in the Prizeya geobotanical district (Isachenko, 1965). The study area is located in the eastern part of the Amur-Zeya interfluve, subtaiga (broad-leaved-coniferous) subzone. This area demonstrates the most industrial and agricultural development of mentioned above territory (Fig. 1). Vegetation map at a scale of 1 : 25 000 is based on field data (236 geobotanical descriptions); interpretation of Sentinel-2 satellite images was made. The classification scheme of the natural vegetation cover according to the ecological-phytocoenotic (dominant) approach was created. Mapping units are represented by groups of associations. The titles of the legend are the subzonal plant communities. Vegetation types (forest, shrub, meadow) and groups of vegetation types (mires, aquatic and coastal, meadow-shrub) are presented in the subtitles. Forests are divided into classes of formations (light coniferous, coniferous-broad-leaved and coniferous-small-leaved, broad-leaved, broad-small-leaved, small-leaved) and disturbed communities of burned areas (sparse and young forests). Transformed vegetation has been identified in the disturbed territory. The main classification criterion is the type of anthropogenic impact. The map legend contains 45 names with color and hatching (Fig. 4). Equity participation of plant communities of the study area was presented. Disturbed territories occupy large areas of 7946 hectares (27.8 %). The forested area covers 29.7 %, including small-leaved forests (7.2 %) and sparse and young forests 8.0 %). Pine forests and their derivatives pine-oak, oak-pine, birch-pine and pine-birch forests occupy 2.8 %, oak forests — 2.5 %, the broad-small-leaved forests — 3.7 %. A significant area is occupied by meadow vegetation — 22.4 %, mire vegetation accounts for 6.7 %, dwarf birch (yernik) and willows — 4.9 %, aquatic and coastal communities — 1.4 % (Table). The vegetation map shows the main features of vegetation cover of the Prizeya geobotanical district and allows to give a correct botanical-geographic interpretation of the territory.

Primer registro de la “mosca de la madera” 𝑃𝑎𝑛𝑡𝑜𝑝ℎ𝑡ℎ𝑎𝑙𝑚𝑢𝑠 𝑧𝑜𝑜𝑠 (Enderlein, 1931) (Diptera: Pantophthalmidae), para el estado de Morelos, México

Pantophthalmus zoos (Enderlein, 1931), is recorded for the first time in northern Morelos. The specimen was collected attracted to light in the vicinity of the university campus near the vicinity of a pine-oak forest in the northern part of the state of Morelos.

Ecostress Water Balance and Topography Drive Post-Fire Pine Regeneration Patterns in a Madrean Pine-Oak Forest in the Arizona Sky Islands

Ecostress Water Balance and Topography Drive Post-Fire Pine Regeneration Patterns in a Madrean Pine-Oak Forest in the Arizona Sky Islands

Plant community responses to kudzu (Pueraria montana) invasion in a southern upland forest1

Kudzu (Pueraria montana (Lour.) Merr. var. lobata (Willd.)) has long been regarded as one of the most destructive invasive species in temperate forests. Despite this, little is known about the specific impacts of kudzu on native plant communities. In this study we compared plant communities of mixed pine-oak forest sites in Mississippi infested with kudzu to those in uninvaded sites,and asked if kudzu generally suppresses the plant community or has unequal effects on species differing in weediness, shade tolerance, or growth form. At each site we determined species richness; percentage of cover of understory species; density of large trees, saplings, and seedlings; and species composition of sample plots. Kudzu-invaded sites had lower species richness, less understory cover, and lower density of woody species than control sites. Species persisting in kudzu-invaded sites were a subset of species found in control sites, and persistence was unrelated to growth form, weediness, or shade tolerance. Both light limitation and nitrogen fixation by kudzu may be related to these results but further study will be required to evaluate their relative impact on kudzu-invaded communities.

Assessment of the Consequences of Forest Fires in 2020 on the Territory of the Chornobyl Radiation and Ecological Biosphere Reserve

The article presents the consequences of fires that occurred on the territory Chornobyl Radiation and Ecological Biosphere Reserve in April 2020. Research shows that the results of these events characterized as catastrophic. The condition of forests after fires was assessed using satellite data and field trips to review the condition of forests affected by wildfires. The total area affected by the fire in 4 foci was 51,806.5 hectares. The total area of fires in the exclusion zone is 66,222.5 hectares. About 25% of the territories affected by the fires have changed. To preserve the landscape diversity and mosaic of areas covered and not covered with forest vegetation, it is impractical to conduct afforestation (afforestation of fallows) on the territory of the reserve. Among the forests affected by fires, the majority has a high ecological and forestry potential and, accordingly, a high potential for natural recovery (81.6%). In dead forests, the share with a high potential for natural reforestation is slightly lower and amounts to 66.8%. The share of forests with low natural recovery potential is low and amounts to 1.9% and 4.8% in forests affected by fires and dead, respectively. Significantly damaged, and sometimes destroyed, were a number of rare settlements, which are not only important for nature conservation, but also classified by the Standing Committee of the Bern Convention (Resolution 4) as particularly valuable settlements, as well as the “Green Book of Ukraine” (2009). 2 groups were marked as excessively damaged on the territory of the reserve. It should be noted that there is a slight general violation of the protected core of this object of the nature reserve fund, which will allow it to preserve its environmental potential and the functions of protecting and reproducing biodiversity. Most of the areas of the reserve affected by fires have a high forestry potential and are able to recover independently, so they do not require intervention in natural processes for reforestation. The degree of transformation of the ground cover in pine and oak-pine forests of the reserve under the influence of pyrogenic factor is determined by the intensity of the fire. Reforestation in areas with low forest potential should be carried out with clear planning

Intra- and Inter-Annual Growth Patterns of a Mixed Pine-Oak Forest under Mediterranean Climate

Temperature and precipitation variability throughout the year control the intra-annual dynamics of tree-ring formation. Physiological adaptation of trees to climate change is among the key issues to better understand and predict future forest performance and composition. In this study, we investigated the species’ coexistence and performance of Scots pine and pubescent oak growing in a mixed sub-Mediterranean forest in the northeast of the Iberian Peninsula. We assessed intra-annual cumulative growth patterns derived from band dendrometers during four consecutive growing seasons and long-term changes in basal area increment for the period 1950–2014. Our results revealed that Scots pine followed an intra-annual bimodal growth pattern. Scots pine growth was mainly limited by water availability at intra-annual, interannual and decadal time scales, which resulted in a negative long-term growth trend. Conversely, oak displayed a unimodal growth pattern, which was less climatically constrained. A significant increase in basal area of oak denotes an overall better potential acclimation to prevailing climatic conditions at the expenses of a higher risk of physiological failure during extreme climate events.

Rapid Ecological Integrity Assessment Metrics to Restore Wildlife Habitat and Biodiversity for Shortleaf Pine–Oak Ecosystems

Open woodlands dominated by shortleaf pine (Pinus echinata Mill.) and oak are historically an important component of the landscape across the southeastern United States. These ecosystems support numerous wildlife species, many of which have declined in recent years as the amount and condition of their habitat have declined. Land managers and private landowners need guidance on how to efficiently and accurately quantify the condition and wildlife habitat value of the pine stands that they manage. Here we provide a set of rapid assessment metrics, based on NatureServe’s ecological integrity assessment (EIA) method, to (a) identify exemplary tracts that provide the best habitat for key wildlife species, and (b) monitor restoration efforts to assess progress toward the improved quality of existing tracts. To ensure an ecologically appropriate scaling of metrics, we distinguished six types of shortleaf pine–oak woodland: A.—Interior Highlands shortleaf pine–oak (including A.1—shortleaf pine–oak forest and woodlands; A.2—shortleaf pine–bluestem woodlands); B—montane longleaf pine–shortleaf pine woodlands; C—southern Appalachian pine–oak woodlands; D—West Gulf coastal plain shortleaf pine–oak woodlands; and E—southeast coastal plain and Piedmont shortleaf pine–oak woodlands. We relied on a narrative conceptual model and peer review-based indicator selection to identify a core set of 15 stand-level metrics (two were optional). Individual assessment points (thresholds) and ratings (Excellent, Good, Fair, and Poor) were developed that were sensitive to the distinct attributes of each of the five shortleaf pine–oak and Appalachian pine–oak types. Values for the metrics can all be collected using rapid field methods, such as using basal area prisms and ocular (visual) estimates of cover. Protocols for the consistent application of these EIA methods are provided. A case study is presented from the Cherokee National Forest in Tennessee. These methods provide improved and rapid EIA metrics for all shortleaf pine–oak ecosystems in the southeastern US to help guide conservation-minded landowners in assessing the biodiversity and priority wildlife values of shortleaf pine–oak and southern Appalachian pine–oak ecosystems.

Quantifying Crown Morphology of Mixed Pine-Oak Forests Using Terrestrial Laser Scanning

Mixed forests make up the majority of natural forests, and they are conducive to improving the resilience and resistance of forest ecosystems. Moreover, it is in the crown of the trees where the effect of inter- and intra-specific interaction between them is evident. However, our knowledge of changes in crown morphology caused by density, competition, and mixture of specific species is still limited. Here, we provide insight on stand structural complexity based on the study of four response crown variables (Maximum Crown Width Height, MCWH; Crown Base Height, CBH; Crown Volume, CV; and Crown Projection Area, CPA) derived from multiple terrestrial laser scans. Data were obtained from six permanent plots in Northern Spain comprising of two widespread species across Europe; Scots pine (Pinus sylvestris L.) and sessile oak (Quercus petraea (Matt.) Liebl.). A total of 193 pines and 256 oaks were extracted from the point cloud. Correlation test were conducted (ρ ≥ 0.9) and finally eleven independent variables for each target tree were calculated and categorized into size, density, competition and mixture, which was included as a continuous variable. Linear and non-linear multiple regressions were used to fit models to the four crown variables and the best models were selected according to the lowest AIC Index and biological sense. Our results provide evidence for species plasticity to diverse neighborhoods and show complementarity between pines and oaks in mixtures, where pines have higher MCWH and CBH than oaks but lower CV and CPA, contrary to oaks. The species complementarity in crown variables confirm that mixtures can be used to increase above ground structural diversity.

Great Tits’, Parus major (Passeriformes, Turdidae), Diet in Transformed Forest Ecosystems of Northeastern Ukraine

Abstract The diet spectrum of the great tit (Parus major L., 1758) was studied in transformed forests of northeastern Ukraine. Four forest ecosystems were surveyed: four model sites in oak woodlands and in a pine–oak forest with different stages of recreational digression. Forty-seven taxa of invertebrates (n = 325) were detected in the ration of great tit chicks. Insecta (72.4%): Lepidoptera (seven families, 35.9%), Hymenoptera (two families, 21.0%), Diptera (seven families, 2.7%) and Coleoptera (four families, 1.8%) were among them. In terms of the qualitative composition of invertebrates (20 species, 42.6%) and the proportion of seized food objects (159 objects), phytophages prevailed. The food composition of great tit chicks was the most similar in territories MS1 and MS4. It contained six common taxa for these territories (Stugren–Radulescu Index = 0.7, Jaccard = 0.2, Sorensen = 0.3).

Abronia fuscolabialis (ANGUIDAE; GERRHONOTINAE)

We describe four new records of Abronia fuscolabialis at Sierra Juárez, northern Oaxaca. These records are separated between 33 and 35 km to the south of the specimen previously reported from Sierra Júarez, and between 34 and 36 km to the west of the nearest specimen reported from Sierra Mixe. Despite being reported only for cloud forests, we recorded it in pine-oak forests