Group Of Beetles Research Articles

A decadal study reveals that restoration guided by an umbrella species does not reach target levels

Abstract Maintaining structural and functional elements of ecosystems are essential in order to preserve biodiversity and ecosystem function. As a means of guiding conservation work, the umbrella species concept was developed. In Sweden, one putative umbrella species, the white‐backed woodpecker, has guided conservation and restoration of deciduous forests for two decades. Here, we evaluate the decadal effects of restoration aimed at the white‐backed woodpecker on biodiversity of saproxylic beetles. We compare stands that were restored 12 to 21 years ago to non‐restored stands and historical white‐backed woodpecker habitats acting as restoration target stands. Restored stands contained higher deciduous deadwood volumes than non‐restored stands but lower volumes than restoration target stands. The deadwood in restored stands was concentrated in later decay stages, whereas target stand deadwood was more evenly distributed across decay stages. Restored stands had similar species richness and abundance of most groups of saproxylic beetles compared with non‐restored stands while not reaching the levels of restoration target stands. Species assemblages differed among all stand types with restored stands supporting late decay stage and generalist species while target stands supported more deciduous associated and threatened species. Synthesis and applications: We conclude that after one to two decades, restoration improve stand structure and benefit beetle diversity but that target levels are not yet reached. Thus, only partial restoration is achieved. Our results stress that for restoration to be successful both continuous and repeated restoration efforts are needed and that it is important to identify target levels of important habitat characteristics when assessing restoration outcome.

Illuminating Firefly Diversity: Trends, Threats and Conservation Strategies.

Fireflies are a diverse group of bioluminescent beetles belonging to the family Lampyridae. Recent research on their diversity, evolution, behavior and conservation has greatly advanced our scientific understanding of these charismatic insects. In this review, we first summarize new discoveries about their taxonomic and ecological diversity, then focus on recent endeavors to identify and protect threatened fireflies around the world. We outline the main threats linked to recent population declines (habitat loss and degradation, light pollution, pesticide overuse, climate change and tourism) and describe relevant risk factors that predict which species will be particularly vulnerable to these threats. Although global coordination of firefly conservation efforts has begun only recently, considerable progress has already been made. We describe work by the IUCN SSC Firefly Specialist Group to identify species currently facing elevated extinction risks and to devise conservation strategies to protect them. To date, IUCN Red List assessments have been completed for 150 firefly taxa, about 20% of which face heightened extinction risks. The conservation status for many species has yet to be determined due to insufficient information, although targeted surveys and community science projects have contributed valuable new data. Finally, we highlight some examples of successful firefly habitat protection and restoration efforts, and we use the framework of the IUCN SSC Species Conservation Cycle to point out high-priority actions for future firefly conservation efforts.

When a key innovation becomes redundant: Patterns, drivers and consequences of elytral reduction inColeoptera

AbstractThe transformation of the fore wings into strongly sclerotized protective covers (elytra) is considered a fundamental evolutionary innovation of the megadiverse order Coleoptera. Surprisingly, these multifunctional structures have been reduced in many distantly related groups of beetles. Patterns, drivers and the evolutionary implications of this modification have never been comprehensively discussed. In the present study, we surveyed the entire order Coleoptera to analyse the patterns of elytral shortening and loss, with a special focus on prevalence, forms, degree of reduction and the functional background of this significant deviation from the coleopteran ground plan. Our analysis revealed that about 20% of all extant species (roughly 88,000 out of 442,275 spp.), distributed across all four suborders, have shortened or even absent elytra. The elytral loss was more frequent within the polyphagan series Elateriformia and Staphyliniformia. Moreover, we found that elytral reduction has independently occurred multiple times in the evolutionary history of Coleoptera and that it has been driven by a wide array of selective drivers. One of the main drivers is the improved flexibility of the uncovered abdomen and the correlated increased manoeuvrability in narrow spaces, as well as the option of using the flexible abdomen as a steering organ or to facilitate mating. Another common driver is mimicry, where exposed metathoracic wings potentially improve the overall similarity to hymenopteran models. Exposure of the abdomen can facilitate the targeted release of defensive abdominal gland secretions and was most likely a crucial step towards establishing relations with social insects enhanced by chemical communication. In the Elateriformia, and rarely in other lineages, elytral loss is a consequence of paedomorphosis, related to a specific resource‐allocation strategy. In many groups of beetles with reduced elytra, alternative defensive strategies can be found. This includes, for instance, aposematic coloration, chemical defence, mimicry or bioluminescence. Direct drivers of elytral loss in many groups remain unclear, and more studies are needed to understand the evolutionary background and implications of this significant morphological modification in Coleoptera.

Ground beetle assemblages inhabiting various age classes of Norway spruce stands in north-eastern Poland.

Assemblages of epigeic ground beetles living in Norway spruce forests in north-eastern Poland in three age ranges: young: 20-30 years (A); middle-aged: 40-50 years (B); old: 70-80 years (C) were investigated. In each age category, 4 plots with 5 Barber traps were set up. Ground beetle assemblages were compared in terms of their abundance, species richness, and the Shannon H' index value. Quantitative ecological description of the carabids captured in the analysed age-classes of Norway spruce forests was performed, and the values of the mean individual biomass (MIB) were calculated. To determine the correlation between mean individual biomass and abundance of various ecological groups of carabid beetles, the Spearman rank correlation coefficient was calculated. The assemblages of ground beetles living in the Norway spruce forests in north-eastern Poland were characterised by quite large species richness (44 species in total). There were significant differences in species richness among the different ages of Norway spruce forests. The oldest Norway spruce stands (70-80 years old) had a smaller number of species and specimens of ground beetles as well as the highest MIB values in comparison with the younger spruce forests A and B. The results revealed that high MIB values were positively correlated with the presence of large ground beetle species with higher moisture requirements. Lower values of the MIB index were due to the presence of smaller open habitat macropterous species, with the spring type of breeding and associated with open areas.

Diversity Of Coleoptera Order Soil Insects In Kerandangan Nature Park Area

Diversity Of Coleoptera Order Soil Insects In Kerandangan Nature Park Area TWA Kerandangan is a conservation area located in West Nusa Tenggara Province. There are types of plants and animals in TWA Kerandangan that show acceptable and stable ecosystem conditions based on the role of insects. One type of insect that plays a role in the balance of the ecosystem is soil insects because they are considered good organic matter breakers. The order of soil insects that has a valuable role in the ecosystem is Coleoptera-decomposing wildlife feces. Analysis of their diversity is very important for the sustainability of the ecosystem in Kerandangan TWA. The research method used was pitfall trapping. The diversity level of the Coleoptera diurnal group is included in the low category because it has an average index value of 0.93, and the level of diversity of the Coleoptera nocturnal group is included in the medium category because it has an average index value of 1.34. The dominance index value is < 0.50, which indicates that no species dominates at each station, and the level of evenness is in the low to high category. The most common Coleoptera species found is Onthophagus sp 4, and Onthopagus taurus belongs to the dung beetle group (Scarabaeidae).

An unusual artematopodid beetle from Early Cretaceous Wealden amber (Coleoptera: Elateroidea: Artematopodidae)

Early Cretaceous Wealden amber of the Isle of Wight (early Barremian, ~125 Ma) represents one of the oldest known fossiliferous ambers. Here we describe the first fossil beetle from the deposit, and first British coleopteran amber inclusion, the artematopodid Valdopogon simpsoni gen. et sp. nov. Despite its fragmentary nature, the fossil possesses a puzzling combination of characters unseen in modern Artematopodidae, namely equally long abdominal ventrites I and II, concave sutures between ventrites I–V, and absence of elytral striation. Valdopogon contributes to our understanding of the morphological evolution of this once diverse group of elateroid beetles.

Effects of heterogeneity on the ecological diversity and redundancy of forest fauna

Heterogeneity in forests might promote biodiversity not only through an increase in niche volume but also through other processes, such as an increase in resources and their spatial distribution. However, negative relationships between heterogeneity and biodiversity have also been observed, which may indicate that heterogeneity acts as a filter for some species. This study examined the effects of different facets of heterogeneity in forest stands, i.e. deadwood, plant diversity, forest stand structure, and micro-scale topography, on the ecological (functional-phylogenetic) diversity and redundancy of nine animal groups: moths, true bugs, different functional groups of beetles, spiders, birds, and bats. Overall, we found positive effects of heterogeneity on ecological diversity and redundancy. Although the effect of heterogeneity at the local scale was moderate compared with the general effect of region, greater heterogeneity could be beneficial to some species groups and lead to more resilient species communities.

Phylogenomics illuminates the phylogeny of flower weevils (Curculioninae) and reveals ten independent origins of brood-site pollination mutualism in true weevils.

Weevils are an unusually species-rich group of phytophagous insects for which there is increasing evidence of frequent involvement in brood-site pollination. This study examines phylogenetic patterns in the emergence of brood-site pollination mutualism among one of the most speciose beetle groups, the flower weevils (subfamily Curculioninae). We analysed a novel phylogenomic dataset consisting of 214 nuclear loci for 202 weevil species, with a sampling that mainly includes flower weevils as well as representatives of all major lineages of true weevils (Curculionidae). Our phylogenomic analyses establish a uniquely comprehensive phylogenetic framework for Curculioninae and provide new insights into the relationships among lineages of true weevils. Based on this phylogeny, statistical reconstruction of ancestral character states revealed at least 10 independent origins of brood-site pollination in higher weevils through transitions from ancestral associations with reproductive structures in the larval stage. Broadly, our results illuminate the unexpected frequency with which true weevils-typically specialized phytophages and hence antagonists of plants-have evolved mutualistic interactions of ecological significance that are key to both weevil and plant evolutionary fitness and thus a component of their deeply intertwined macroevolutionary success.

Knowledge of ground‐dwelling beetle communities in the tropical Andes: Gaps and trends

AbstractThe tropical Andes is one of the most biodiverse ecoregions on Earth, exhibiting high levels of species endemism. The tropical Andes is also one of the most vulnerable ecoregions worldwide due to a long history of anthropogenic transformations. One of the major obstacles for generating conservation plans is gaps in knowledge about the status and threats to many groups of Andean biodiversity, especially invertebrates. Focusing on three important beetle groups (i.e., Coleoptera: ground beetles, rove beetles and dung beetles) in the tropical Andes, we performed a systematic review of scientific literature retrieving 50 studies that allowed us to assess the degree of knowledge across the region, disturbance types, and biodiversity metrics used. We found a high representation of studies in Colombia, compared with other Andean countries. We also found a marked bias among taxonomic groups, topics or metrics evaluated, with dung beetles the most represented group, particularly in studies addressing forest conversion using metrics such as species richness or abundance. We reveal large gaps in information on the diversity of ground and rove beetles, and in the use of other diversity metrics. The lack of information across countries makes it difficult to generalize results and points to the need for more research, especially in under‐represented countries such as Bolivia and Venezuela. Including complementary response metrics, such as biomass, functional diversity or ecological functions, will improve the assessment of human impacts on tropical Andean beetle communities and wider ecosystems.

Traditional prescribed burning of coastal heathland provides niches for xerophilous and sun-loving beetles

In Western Norway, farmers have traditionally used fire as a management tool in coastal heathlands to enhance the fodder quality for livestock. Rotational prescribed burning increases landscape heterogeneity by creating a mosaic of different regeneration stages of heather. Ground beetle (Coleoptera: Carabidae) responses to fire in traditionally managed coastal heathland have already been studied, but less is known about other beetle groups in this system. We compared the beetle activity between patches of mature and recently burnt heath, by looking at diversity indices, species composition and ecological preferences and traits. Contrary to previous studies, we did not find an increase in beta diversity after disturbance, but we found that prescribed burning offers micro-environmental conditions which enhanced the activity of sun-loving and xerophilous species. We also identified new indicator species for both mature and pioneer heath in five beetle families: Carabidae, Staphylinidae, Curculionidae, Leiodidae, and Scirtidae. Rotational prescribed burning was confirmed to be an efficient conservation tool for specialists without affecting the overall diversity of the site. We recommend the use of several taxa, ecological preferences and traits to assess the impact of prescribed burning and to monitor the condition of traditionally managed coastal heathlands.

Can mollusks or insects serve as bioindicators of the risk element polluted area? Gastropods (Gastropoda) versus leaf beetles (Coleoptera: Chrysomelidae).

Two groups of invertebrates, terrestrial mollusks (Gastropoda) and Chrysomela populi leaf beetles (Coleoptera: Chrysomelidae), were sampled to estimate the suitability of these organisms as bioindicators of risk element pollution (predominantly Cd, Pb, and Zn) alongside the risk element concentration gradient in the contaminated area (former mining/smelting areas in the vicinity of Příbram city, Central Bohemia, Czech Republic). The individuals representing ten species of terrestrial snails and imagoes of C. populi were collected manually at five sampling sites, differing in the level of soil contamination with risk elements. The findings showed high variability of the results regardless of the element determined, animal species, and sampling location. Among the elements, higher accumulation ability was observed for Cd and Zn, given the higher bioaccessibility of these elements in soils compared to Pb, Cr, and Cu. Higher Cd and Zn accumulation in the soft tissues of gastropods (without any statistically significant differences among the species) compared to C. populi was also recorded. Medians of the bioaccumulation factors (BAFs) reached up to 33.2 for Cd and 5.8 for Zn, in gastropods while reaching up to 3.4 for Cd, and 2.3 for Zn, for C. populi. For both groups of organisms, paradoxically, a higher rate of accumulation of risk elements was observed in all analyzed organisms in sites with lower soil contamination compared to heavily contaminated sites. This indicated the ability of the organisms living in extreme conditions to avoid the uptake of these elements or to move among areas of different contamination levels. Thus, terrestrial gastropods and C. populi proved to be unsuitable bioindicators for assessing soil pollution.

X-ray micro-computed tomography of minute hooded beetles (Coleoptera: Corylophidae) reveals its hidden paleodiversity in the Eocene Baltic amber

Fossil Corylophidae are poorly known. Three fossil representatives of the family were described until now: one from mid-Cretaceous (Mesozoic) and two from Eocene (Cenozoic) deposits. We revise corylophid material from Baltic amber using X-ray micro-computed tomography (μCT) and describe two new species: Clypastraea venedorum n. sp. and C. groehni n. sp. The systematic placement of the previously described Baltic amber fossil Clypastraea primainterparesAlekseev, 2016 was confirmed. The re-description and diagnosis will help the systematic study on the extant and extinct species of the family. Micro-CT was used for the first time to study a members of Corylophidae. An identification key for Eocene representatives of the genus Clypastraea is provided. The species-rich palaeofauna of this group of corylophid beetles (the most diverse fossil record to date) is briefly discussed in the context of diverse plant communities of Eocene amber forest.

Climate Change Impacts on the Potential Distribution Pattern of Osphya (Coleoptera: Melandryidae), an Old but Small Beetle Group Distributed in the Northern Hemisphere.

Exploring the development of species distribution patterns under climate change is the basis of biogeography and macroecology. However, under the background of global climate change, few studies focus on how the distribution pattern and the range of insects have or will change in response to long-term climate change. An old but small, Northern-Hemisphere-distributed beetle group Osphya is an ideal subject to conduct the study in this aspect. Here, based on a comprehensive geographic dataset, we analyzed the global distribution pattern of Osphya using ArcGIS techniques, which declared a discontinuous and uneven distribution pattern across the USA, Europe, and Asia. Furthermore, we predicted the suitable habitats of Osphya under different climate scenarios via the MaxEnt model. The results showed that the high suitability areas were always concentrated in the European Mediterranean and the western coast of USA, while a low suitability exhibited in Asia. Moreover, by integrating the analyses of biogeography and habitat suitability, we inferred that the Osphya species conservatively prefer a warm, stable, and rainy climate, and they tend to expand towards higher latitude in response to the climate warming from the past to future. These results are helpful in exploring the species diversity and protection of Osphya.

Taxonomic revision of the genus Parena Motschulsky, 1860(Coleoptera, Carabidae, Lebiini, Metallicina).

The present contribution revises the genus Parena Motschulsky, 1860, a group of arboreal carabid beetles with 46 recognized species, distributed in Tropical Asia, Sub-Saharan Africa, and the north and east coastal Australasia. We re-evaluate the infrageneric taxonomy of the genus and redefine three subgenera: Parena s. str., Bothynoptera Schaum, 1863 and Crossoglossa Chaudoir, 1872, based on the morphological characters of external features, male genitalia and female ovipositors. Under these three subgenera, we define 14 species groups to contain all known species. Keys for the identification of all subgenera, species groups, and species are provided, along with diagnostic characters, included species, geographical distribution, brief discussion on monophyly and relationships for each subgenus and species group, ample species descriptions, distribution maps, habitus images, and genitalia illustrations. The previous alpha-taxonomy of the genus Parena is defective, and several species were described without genital morphological comparisons with their real adelphotaxon. Based on careful examination of a large amount of type materials, we propose 19 new synonyms: P. rufotestacea Jedlička, 1934, as a junior synonym of P. cavipennis (Bates, 1873); P. perforata (Bates, 1873), P. nepalensis Kirschenhofer, 1994, and P. kunmingensis Kirschenhofer, 1996, as junior synonyms of P. dorsigera (Schaum, 1863); P. wrasei Kirschenhofer, 2006, as a junior synonym of P. kurosai Habu, 1967; P. nantouensis Kirschenhofer, 1996 and P. kataevi Kirschenhofer, 2006, as junior synonyms of P. tesari (Jedlička, 1951); P. yunnana Kirschenhofer, 1994, as a junior synonym of P. shapingensis Xie & Yu, 1993; P. albomaculata Habu, 1979, as a junior synonym of P. malaisei (Andrewes, 1947); P. koreana Kirschenhofer, 1994, as a junior synonym of P. monostigma (Bates, 1873); P. phongsalyensis Kirschenhofer, 2011, as a junior synonym of P. quadrisignata Mateu, 1977; P. sellata (Heller, 1921), P. hastata (Heller, 1921), P. sellatoides (Jedlička, 1940), P. fasciata var. unicolor Louwerens, 1949, and P. sumatrana Kirschenhofer, 2011, as junior synonyms of P. fasciata (Chaudoir, 1872); P. nigrolineata nipponensis Habu, 1964 and P. schillhammeri Kirschenhofer, 2006, as junior synonyms of P. nigrolineata (Chaudoir, 1852); and P. alluaudi Jeannel, 1949, as a junior synonym of P. madagascariensis (Alluaud, 1917). Furthermore, the specific status of P. scutata (Alluaud, 1917) is resurrected from synonym with P. plagiata Motschulsky, 1864. Parena sticta (Andrewes, 1947) is excluded from Parena and a new combination is suggested: Peliocypas stictus (Andrewes, 1947) comb. nov. A total of eight new species are described: P. (Crossoglossa) sciakyi sp. nov. (type locality: Guadalcanal, Solomon Islands), P. (Bothynoptera) heteronycha sp. nov. (type locality: Houaphan, Laos), P. (Bothynoptera) emarginata sp. nov. (type locality: Muli, Sichuan, China), P. (Bothynoptera) gonggaica sp. nov. (type locality: Hailuogou, Sichuan, China), P. (Bothynoptera) triguttata sp. nov. (type locality: Kangding, Sichuan, China), P. (Parena) picipes sp. nov. (type locality: Trus Madi, Borneo), P. (Parena) fulva sp. nov. (type locality: Dodoma, Tanzania), and P. (Parena) ruficornis sp. nov. (type locality: Lobaye, the Central African Republic). Several of these new species are very rare in collections, with four of them known from females only.

Jewels on the go: exotic buprestids around the world (Coleoptera, Buprestidae)

Buprestidae (Coleoptera: Buprestoidea) is one of the three wood-borer beetle groups of major phytosanitary interest worldwide, together with Cerambycidae and Scolytinae (Curculionidae). As in other beetle families, some buprestid species have been unintentionally or intentionally introduced around the world, in some cases causing significant environmental and economic damage in the invaded territories. Despite the phytosanitary relevance of the Buprestidae, information regarding the identity of exotic buprestids, their biogeographic areas of origin, introduction pathways, and larval host plants, have remained scattered in the literature. Our objective was to summarize much of the existing knowledge on these topics in the present paper. Our analysis resulted in a list of 115 exotic buprestids worldwide, representing introductions both within and between biogeographic realms and corresponding to less than 1% of the known buprestid species worldwide. Invasiveness does not seem to be linked to their larval host plant preferences, as introduced species utilize 158 plant genera in 70 plant families and are equally represented in all feeding guilds (monophagous, oligophagous, and polyphagous). As trade of plants or plant parts can serve as a pathway for future introductions, the information reported in this review can help in pest risk assessment.

Effects of post-mining forest restoration and alternative land uses on ground-dwelling arthropods in Ghana

In an Afrotropical region experiencing massive deforestation, restoration approaches should provide sustainable solutions for recovering biodiversity. Arthropods are a sensitive taxonomic group for habitat alteration by deforestation and can be good indicators for restoration studies. Ground-dwelling arthropods provide important ecosystem functions, such as predation or organic matter decomposition, thereby contributing to ecosystem functionality. The consequences of post-mining management on arthropods in the Afrotropical region remain understudied. We carried out a comprehensive sampling of ground-dwelling arthropods in the dry and wet seasons across four land-use types in the semi-deciduous forest zone of Ghana. We then analysed whether the specific tree communities, vegetation structure and seasonal differences affected arthropod communities in the restored post-mining forest compared to the dominant alternative land-use type (agroforestry plantation), a natural reference (natural forest) or an unmanaged former mining area (gravel mine). In total, 43,364 arthropods were sampled and assigned to 78 taxonomic groups representing 14 order/sub-order, 28 beetle families, 25 spider families, 5 hunting guilds of spiders and 6 trophic groups of beetles. Overall, Araneae, Coleoptera, Hymenoptera and Orthoptera all had higher activity densities in the wet season. The vegetation structure of the three land-use types with trees supported a greater overall activity density of arthropods and a more diverse functional composition compared to the unmanaged gravel site. Pronounced variation between the dry and wet seasons further influenced the taxonomic and functional composition. The active forest restoration of this post-mining area is a promising approach to drive arthropod communities towards a comparable state observed in the natural forest.

Kekveus brevisulcatus sp. nov., a new featherwing beetle from mid-Cretaceous amber of northern Myanmar (Coleoptera: Ptiliidae).

Ptiliidae (featherwing beetles) is a group of minute staphylinoid beetles with a scarce fossil record. Here a second member of the Mesozoic genus Kekveus Yamamoto et al. is reported from mid-Cretaceous Burmese amber, with detailed morphology obtained through confocal microscopy. Kekveus brevisulcatus Li, Yamamoto, Newton & Cai sp. nov. shares with K. jason Yamamoto et al. the unpaired medial pronotal fovea and narrowly separated transverse metacoxae, but can be separated from the latter based on its less elongate body, shorter pronotal foveae, and much weaker transverse depression on the head. Our phylogenetic analyses support the discheramocephalin affinity of Kekveus, although its relationship with other members of Discheramocephalini cannot be confidently resolved.

Synopsis of the Colombian Stag Beetles: A baseline for conservation assessments

Stag beetles, or Lucanidae (Insecta: Coleoptera: Scarabaeoidea), are among the most charismatic groups of scarab beetles. However, their ecology and natural history are largely unknown, partly due to their rarity in the field and in biological collections. This contribution summarizes the status of knowledge of the Colombian Lucanidae, based for the most part in bibliographic research and personal observations from fieldwork and biological collections in Colombia and Brazil. Bibliographic records are supplemented by data from the Global Biodiversity Information Facility (GBIF), including field observations recorded through the online platform iNaturalist. In the literature, we found 19 species of stag beetles recorded for Colombia, belonging to five genera, three tribes, and two subfamilies. Bibliographic records are concentrated in the Andean region of Colombia, with some records in the Caribbean and Pacific regions. The lowlands of the Amazon and Orinoco regions lack any records for lucanid beetles. The diversity and ecology of stag beetles in Colombia are discussed in the light of current environmental threats. By presenting diagnoses and an identification key to the lucanid genera present in the country, along with known distributional data, and a discussion about their ecology, this contribution constitutes the first step towards proposing Colombian lucanids as species in need of conservation efforts.

Logging operations creating snags, logs, and stumps under open and closed canopies promote stand-scale beetle diversity

Conservation tools to enrich habitat diversity in the widely distributed homogeneous production forests include stumps as logging residues but also the intentional creation of logs or snags, as well as varying canopy conditions. While an open canopy has been shown to foster forest biodiversity, the impact of different deadwood types at stand scale is less clear, which is crucial since this is the most relevant scale for silvicultural decisions. In this study, we experimentally manipulated canopy conditions (open vs. closed) and created deadwood (stumps, logs, snags) in different combinations in five mature European beech (Fagus sylvatica L.) forests to test the potential of active manipulations to increase the diversity of beetles, one of the most diverse insect orders in temperate forests. We estimated abundance, species number and species richness (controlled for abundance) of saproxylic (i.e., deadwood-dependent) and non-saproxylic beetles using flight-interception traps and analyzed species assemblages within the first 3 years of the experiment. Using generalized linear mixed effect models we found a 33.7 % and 43.4 % higher abundance as well as a 26.1 % and 23.5 % higher species number under open canopies for saproxylic and non-saproxylic beetles respectively, accompanied by a higher species richness of both groups. Stands with deadwood had a 38.6 % and 32.7 % higher species number followed by higher species richness of saproxylic and non-saproxylic beetles compared to stands without manipulation but manipulations did not affect beetle abundances. We identified sampling year, followed by canopy condition and deadwood type (in addition to an overall higher impact of spatial distance between stands and sites) by applying multiple regression analyses as most important to explain species assemblages of both beetle groups. Saproxylic abundance and species number in stump treatments were initially high but decreased over 3 years, while treatments containing snags and logs resulted in an increase in both abundance and species number over time. These temporal trends were mediated by canopy cover. Our findings provide three major insights for biodiversity-orientated management in mature beech forests: First, opening the canopy increases the stand-scale abundance, species number, and species richness of saproxylic and non-saproxylic beetles. Second, while stumps are attractive for saproxylics shortly after the logging operation, snags and logs provide longer-lasting deadwood resources, thus underlining longer sustainability of snag and log enrichment for forest biodiversity. Third, deadwood enrichment at the stand scale promotes not only deadwood-dependent but also other beetle species.

Seasonal Variation of the Community of Chrysomelidae (Coleoptera) in a Temperate Forest at Tamaulipas, Mexico

Seasonal variation and its effect on structure and composition of a Coleoptera community were studied, prompted by fragmentation of land cover in natural areas. Some groups of phytophagous beetles are most abundant during the rainy season, although this contrasts with a greater number of community attributes in the season with less precipitation. The hypothesis of our study was that most chrysomelid specimens and species would be observed at the end of the dry season and beginning of the rainy season, with subfamilies Galerucinae, Eumolpinae, and Cassidinae frequent between seasons. The objective was to analyze seasonal variation of Chrysomelidae in a fragment of temperate forest in northwestern Mexico. A sweep net was used in the understory to capture specimens in quadrants. Specimens captured were in six subfamilies, 24 genera, and 31 species, which varied between dry and rainy seasons. Estimated richness was less at the beginning of the rainy season, which was reflected by the greatest percentage of complementarity, although species were present throughout a season. The greatest dominance of Chrysomelidae was in the rainy season, and largest entropy values at the end of both seasons, while diversity of abundant and dominant species was notable at the end of the dry season. Correspondence analysis revealed three faunal associations, indicating the largest number of species was associated with the end of the dry season and beginning of the rainy season, showing precipitation and ambient temperature were most important variables. The community structure between seasons differed, showing that seasonality provided a wide food resource over time, which generated variation in relative abundance and therefore in composition of chrysomelid species. Results suggested temperature variation and water availability determined establishment of Chrysomelidae among months of the year.