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Specimens of the Peromyscus boylii species group distributed in the western and northeastern montane regions of Michoacán, México, historically have been assigned to P. levipes. Previous studies indicated that these specimens possessed mitochondrial DNA haplotypes that were distinct from both P. levipes and P. kilpatricki, a recently named species in the P. boylii species group from northeastern Michoacán and western Morelos. Herein karyotypic, DNA sequence, and morphological data were analyzed from those populations to evaluate their taxonomic affinity. Karyotypic data indicated that individuals from western Michoacán (Dos Aguas and Aguililla) and from a newly discovered population in northeastern Michoacán (Zinapécuaro) were chromosomally similar to P. carletoni (FN = 68) but distinct from other taxa assigned to the P. boylii species group. Analyses of cranial characteristics indicated that, relative to other species in the P. boylii species group, two morphologically distinct groups were present that corresponded to the Dos Aguas/Aguililla and Zinapécuaro populations, respectively. The latter population, although represented by a small sample size (n = 5 specimens), appeared to exhibit some trenchant morphological distinctions compared with other cryptic species in the P. boylii group. Phylogenetic analyses (parsimony, Bayesian, and likelihood) of DNA sequences obtained from the mitochondrial cytochrome-b gene indicated that although the individuals from Dos Aguas/Aguililla and Zinapécuaro formed a sister group relationship, they formed monophyletic clades that differed genetically (2.54%)—a level approaching that seen between other sister species of Peromyscus. Further, the Dos Aguas/Aguililla and Zinapécuaro clade was more closely aligned with a clade containing representatives of P. carletoni and P. levipes instead of with those from closer geographic proximities (P. kilpatricki) located in eastern Michoacán. Together, these results indicated that these two populations seemingly represent two undescribed species in the P. boylii species group for which we propose the names Peromyscus greenbaumi for populations in western Michoacán (circa Dos Aguas and Aguililla) and Peromyscus ensinki for populations in northeastern Michoacán (circa Zinapécuaro).

An analysis of vicariant speciation of Geotrupes and Phanaeus (Coleoptera, Geotrupidae, Scarabaeidae) from the mountains of Oaxaca, Mexico is undertaken. The new species of dung beetle (Coleoptera: Scarabaeidae) from Oaxaca, Mexico, Phanaeusdionysius sp. n. is described. Photos of the habitus and a distribution map are provided. Phanaeusmalyi Arnaud is revalidated. An updated key for the Phanaeusendymion species group and new localities are also presented. An updated key for the Geotrupes of Oaxaca and new locality records are also submitted.

Peromyscus fraterculus (Miller, 1892) is a small rodent commonly called the northern Baja deermouse. Its pelage is dark, the tail is considerably longer than the body, and the number of caudal vertebrae ranges from 30 to 34. The geographic distribution of P. fraterculus includes the area west of the Colorado River, from southern California in the United States of America southward to the Baja California Peninsula, Mexico, south of La Paz Isthmus. It is found in a broad variety of habitats from sea level to 1,175 m. P. fraterculus does not have special conservation status, although the island populations have conservation issues, mainly due to the introduction of non-native species. It is listed as “Least Concern” (LC) by the International Union for Conservation of Nature and Natural Resources.

A new Allacta xizangensis sp. nov. (Blattodea: Ectobiidae: Pseudophyllodromiinae) is described and assigned to the polygrapha species group. Four known species, A. robusta,A. bimaculata, A. transversa, A. ornata, are re-described and illustrated based on type material and specimens kept in the collection of Southwest University (SWU), Sun Yat-Sen University (SYSU), Hebei University (HBU), China and Institute of Zoology, Chinese Academy of Sciences (IZCAS) and the Russian Academy of Sciences (ZIN). The hitherto unknown male of A. transversa is described with a special display of its genitalia. A key is given to identify the males of Allacta from China. The tarsomere ultrastructure of all the legs of A. ornata was examined by scanning electron microscopy.

Non‐native plants have invaded nearly all ecosystems and represent a major component of global ecological change. Plant invasions frequently change the composition and structure of vegetation communities, which can alter animal communities and ecosystem processes. We reviewed 87 articles published in the peer‐reviewed literature to evaluate responses of arthropod communities and functional groups to non‐native invasive plants. Total abundance of arthropods decreased in 62% of studies and increased in 15%. Taxonomic richness decreased in 48% of studies and increased in 13%. Herbivorous arthropods decreased in response to plant invasions in 48% of studies and increased in 17%, likely due to direct effects of decreased plant diversity. Predaceous arthropods decreased in response to invasive plants in 44% of studies, which may reflect indirect effects due to reductions in prey. Twenty‐two percent of studies documented increases in predators, which may reflect changes in vegetation structure that improved mobility, survival, or web‐building for these species. Detritivores increased in 67% of studies, likely in response to increased litter and decaying vegetation; no studies documented decreased abundance in this functional group. Although many researchers have examined effects of plant invasions on arthropods, sizeable information gaps remain, specifically regarding how invasive plants influence habitat and dietary requirements. Beyond this, the ability to predict changes in arthropod populations and communities associated with plant invasions could be improved by adopting a more functional and mechanistic approach. Understanding responses of arthropods to invasive plants will critically inform conservation of virtually all biodiversity and ecological processes because so many organisms depend on arthropods as prey or for their functional roles, including pollination, seed dispersal, and decomposition. Given their short generation times and ability to respond rapidly to ecological change, arthropods may be ideal targets for restoration and conservation activities.

We present a generic scoring system that compares the impact of alien species among members of large taxonomic groups. This scoring can be used to identify the most harmful alien species so that conservation measures to ameliorate their negative effects can be prioritized. For all alien mammals in Europe, we assessed impact reports as completely as possible. Impact was classified as either environmental or economic. We subdivided each of these categories into five subcategories (environmental: impact through competition, predation, hybridization, transmission of disease, and herbivory; economic: impact on agriculture, livestock, forestry, human health, and infrastructure). We assigned all impact reports to one of these 10 categories. All categories had impact scores that ranged from zero (minimal) to five (maximal possible impact at a location). We summed all impact scores for a species to calculate \"potential impact\" scores. We obtained \"actual impact\" scores by multiplying potential impact scores by the percentage of area occupied by the respective species in Europe. Finally, we correlated species' ecological traits with the derived impact scores. Alien mammals from the orders Rodentia, Artiodactyla, and Carnivora caused the highest impact. In particular, the brown rat ( Rattus norvegicus), muskrat ( Ondathra zibethicus), and sika deer ( Cervus nippon) had the highest overall scores. Species with a high potential environmental impact also had a strong potential economic impact. Potential impact also correlated with the distribution of a species in Europe. Ecological flexibility (measured as number of different habitats a species occupies) was strongly related to impact. The scoring system was robust to uncertainty in knowledge of impact and could be adjusted with weight scores to account for specific value systems of particular stakeholder groups (e.g., agronomists or environmentalists). Finally, the scoring system is easily applicable and adaptable to other taxonomic groups.

The cross-scale resilience model states that ecological resilience is generated in part from the distribution of functions within and across scales in a system. Resilience is a measure of a system's ability to remain organized around a particular set of mutually reinforcing processes and structures, known as a regime. We define scale as the geographic extent over which a process operates and the frequency with which a process occurs. Species can be categorized into functional groups that are a link between ecosystem processes and structures and ecological resilience. We applied the cross-scale resilience model to avian species in a grassland ecosystem. A species' morphology is shaped in part by its interaction with ecological structure and pattern, so animal body mass reflects the spatial and temporal distribution of resources. We used the logtransformed rank-ordered body masses of breeding birds associated with grasslands to identify aggregations and discontinuities in the distribution of those body masses. We assessed cross-scale resilience on the basis of 3 metrics: overall number of functional groups, number of functional groups within an aggregation, and the redundancy of functional groups across aggregations. We assessed how the loss of threatened species would affect cross-scale resilience by removing threatened species from the data set and recalculating values of the 3 metrics. We also determined whether more function was retained than expected after the loss of threatened species by comparing observed loss with simulated random loss in a Monte Carlo process. The observed distribution of function compared with the random simulated loss of function indicated that more functionality in the observed data set was retained than expected. On the basis of our results, we believe an ecosystem with a full complement of species can sustain considerable species losses without affecting the distribution of functions within and across aggregations, although ecological resilience is reduced. We propose that the mechanisms responsible for shaping discontinuous distributions of body mass and the nonrandom distribution of functions may also shape species losses such that local extinctions will be nonrandom with respect to the retention and distribution of functions and that the distribution of function within and across aggregations will be conserved despite extinctions. El modelo de resiliencia transescala establece que la resiliencia ecológica se genera en parte por la distribución de funciones dentro y a través de escalas en el sistema. La resiliencia es una medida de la habilidad de un sistema para permanecer organizado en torno a un conjunto determinado de procesos y estructuras mutuamente reforzadoras, conocido como régimen. Definimos escala como la extensión geográfica en la cual opera un proceso y la frecuencia con que ocurre. Las especies se pueden clasificar en grupos funcionales que son un vínculo entre los procesos del ecosistema y la resiliencia ecológica. Aplicamos el modelo de resiliencia transescala a especies de aves en un ecosistema de pastizal La morfología de una especies esta determinada en parte por su interacción con la estructura y patrón ecológico, de tal modo que la masa corporal de un animal refleja la distribución espacial y temporal de los recursos. Utilizamos la masa corporal, ordenada por rangos y transformada logarítmicamente, de aves asociadas a pastizales para identificar agregaciones y discontinuidades en la distribución de esas masas corporales. Evaluamos la resiliencia transescalar con base en 3 medidas: número total de grupos funcionales, número de grupos funcionales dentro de una agregación, y la redundancia de grupos funcionales en las agregaciones. Evaluamos el efecto de la pérdida de especies amenazadas sobre la resiliencia transescalar mediante la remoción de especies amenazadas del conjunto de datos y el nuevo cálculos de las 3 medidas. También determinamos si se retenía más función que lo esperado después de la pérdida de especies amenazadas mediante la comparación de la pérdida observada con la pérdida aleatoria simulada en un proceso Monte Cario. La distribución observada de la función comparada con la pérdida aleatoria simulada indicó que se retenía mas funcionalidad que la esperada en el conjunto de datos observados. Con base en nuestros resultados, consideramos que un ecosistema con un complemento completo de especies puede sustentar considerables pérdidas de especies sin que se afecte la distribución de funciones dentro y entre agregaciones, aunque la resiliencia ecológica se reduce. Proponemos que los mecanismos responsables de moldear las distribuciones discontinuas de la masa corporal y la distribución no aleatoria defunciones también puede moldear la pérdida de especies, como extinciones locales, serán no aleatorios con respecto a la retención y distribución de funciones y que la distribución de la función dentro y entre agregaciones se conservará no obstante las extinciones.

Reintroduction of fire and grazing, alone or in combination, has increasingly been recognized as central to the restoration of North American mixed-grass and tallgrass prairies. Although ecological studies of these systems are abundant, they have generally been observational, or if experimental, have focused on plant species diversity. Species diversity measures alone are not sufficient to inform management, which often has goals associated with life-form groups and individual species. We examined the effects of prescribed fire, light cattle grazing, and a combination of fire and grazing on three vegetation components: species diversity, groups of species categorized by life-form, and individual species. We evaluated how successful these three treatments were in achieving specific management goals for prairies in the Iowa Loess Hills (U.S.A.). The grazing treatment promoted the greatest overall species richness, whereas grazing and burning and grazing treatments resulted in the lowest cover by woody species. Burning alone best achieved the management goals of increasing the cover and diversity of native species and reducing exotic forb and (predominantly exotic) cool-season grass cover. Species-specific responses to treatments appeared idiosyncratic (i.e., within each treatment there existed a set of species attaining their highest frequency) and nearly half of uncommon species were present in only one treatment. Because all management goals were not achieved by any one treatment, we conclude that management in this region may need refining. We suggest that a mosaic of burning and grazing (alone and in combination) may provide the greatest landscape-level species richness; however, this strategy would also likely promote the persistence of exotic species. Our results support the need to consider multiple measures, including species-specific responses, when planning and evaluating management.

Whenever individuals live in stable social groups and not all individuals breed, group members may breed cooperatively. While well-documented in a variety of birds and mammals, there is some controversy over whether, and to what degree, sciurid rodents breed cooperatively. We identify cooperative breeding when: individuals delay dispersal beyond reproductive maturity, reproduction in mature individuals is suppressed, and when non-breeders provide alloparental care. In this paper we note that the 14 species of marmots (Marmota spp.), large ground-dwelling sciurid rodents found throughout the Northern Hemisphere, provide an excellent taxon in which to study the evolution of cooperative breeding. Marmot species fit none, some, or all of the attributes of cooperative breeding. Most interestingly, delayed dispersal and alloparental care may be de-coupled interspecifically, and possibly intraspecifically, making marmots an excellent taxon for additional study. Environmental harshness increases maturation time and is associated with dispersal delayed beyond reproductive maturity. The opportunity to gain direct fitness may be associated with gaining indirect fitness by alloparental behavior. In addition to its theoretical attraction, cooperative breeding has profound implications for conservation and management of species that breed cooperatively. To maximize marmot production, managers and breeders need to pay particular attention to social group structure to prevent the expression of reproductive suppression. If cooperative breeding results from an environmental constraint, habitat modifications may increase the percent of females that breed.