Dung Beetle Conservation: Effects of Habitat and Resource Selection (Coleoptera: Scarabaeoidea)

There is increasing concern about the conservation of dung beetles which are threatened by several peculiar dangers world-wide, both at the population and community level. A noticeable threat in Europe is the dramatic reduction in the number of cattle and sheep grazing in the open, which is associated with both intensive agriculture and the progressive reforestation of previously pastured areas. We studied dung beetle habitat and resource preferences at La Mandria Park (north-west Italy) which is a mosaic of open and wooded patches where domestic (cows and horses) and wild ungulates (deer and wild boar) co-exist. Scarabaeidae were numerically dominant, accounting for 61.5% of the approximately 3000 individuals sampled (Aphodiidae accounted for 32.5% and Geotrupidae for only 6%). However, when species richness was considered, Aphodiidae were dominant, with 17 of the 27 species found (Scarabaeidae with eight and Geotrupidae with two). Assuming a null hypothesis of equal probability of colonizing any habitat or faeces, we found that most species were significantly associated with one of the four dung types or with one of the two habitats considered. On average, Scarabaeidae preferred cattle dung and open habitats whereas most Aphodiidae used deer lumps and wooded habitats. In spite of the precise ecological choices observed at La Mandria, surveys from other European areas suggest that both habitat and food selection are quite flexible. From a conservation viewpoint, the ability of coprophagous beetles to choose herbivore faeces according to their availability and to select habitats that satisfy their own microclimate requirements may certainly be useful in preserving biodiversity. Agroecology, which implies some woodland and hedgerow management practices associated with pastoralism, could be the right approach to the management of the agricultural landscape. Conversely, in reforested areas, while wild ungulate populations should be preserved, some form of human disturbance, particularly clearings used for pastoralism, should also be maintained.     

New species of scarabaeoid beetles from the family Glaresidae (Coleoptera: Scarabaeoidea) from the Cretaceous of Transbaikalia

A new species from the family Glaresidae, Cretoglaresis ovalis, sp. nov., is described from the Lower Cretaceous site Baisa in Transbaikalia. Improved diagnosis of the genus Cretoglaresis Nikolajev, 2007 is given.     

Climatic stress, food availability and human activity as determinants of endemism patterns in the Mediterranean region: the case of dung beetles (Coleoptera, Scarabaeoidea) in the Iberian Peninsula

Abstract. A study to assess the influence of abiotic (climatic conditions) and biotic factors (food resources, habitat preference and human activity) on endemism patterns of dung beetles in the Mediterranean region was conducted in the Iberian Peninsula and the Balearic Islands. The Thermicity Index (It), the Mediterraneity Index (Im3) and the Aridity Index (Ia) were used to assess the influence of abiotic factors. Relative rabbit density (DR), the proportion of landscape used historically for grazing by sheep and goats and the nature of the food resource were used to assess the influence of biotic factors. Relative endemism (EN) of dung beetle assemblages was positively and significantly related with all of the factors considered. However, the Aridity and Mediterraneity Indices are the best predictors of EN. The predicted endemism (EN = 0.017 Ia + 0.004 Im3 + 0.422) was highly positively and significantly related with the observed endemism. Dung beetle assemblages with the highest relative endemism were observed in the south-eastern part of the Iberian Peninsula. This distribution corresponded to the highest Aridity and Mediterraneity. In contrast, dung beetle assemblages with lower endemism were located in more humid and temperate areas. Assemblages of dung beetles with the highest endemism comprise many species adapted to aridity and the exploitation of dry dung pellets. Conservation of traditional grazing activity by pellet-dropping sheep and goats might benefit the maintenance of dung beetle biodiversity in Mediterranean ecosystems.     

Rediscovery of Tomarus cuniculus (Fabricius, 1801) (Coleoptera: Scarabaeidae: Dynastinae) in Mexico

After more than 80 years, the rediscovery of Tomarus cuniculus in Mexico is presented based on two male specimens recently collected from Tabasco. Historical records from the literature are reviewed. A modification to the identification key of the species of Tomarus in Mexico is provided.     

Modelling the species richness distribution of French dung beetles (Coleoptera, Scarabaeidae) and delimiting the predictive capacity of different groups of explanatory variables

Aim To predict French Scarabaeidae dung beetle species richness distribution, and to determine the possible underlying causal factors. Location The entire French territory has been studied by dividing it into 301 grid cells of 0.72 × 0.36 degrees. Method Species richness distribution was predicted using generalized linear models to relate the number of species with spatial, topographic and climate variables in grid squares previously identified as well sampled (n = 66). The predictive function includes the curvilinear relationship between variables, interaction terms and the significant third‐degree polynomial terms of latitude and longitude. The final model was validated by a jack‐knife procedure. The underlying causal factors were investigated by partial regression analysis, decomposing the variation in species richness among spatial, topographic and climate type variables. Results The final model accounts for 86.2% of total deviance, with a mean jack‐knife predictive error of 17.7%. The species richness map obtained highlights the Mediterranean as the region richest in species, and the less well‐explored south‐western region as also being species‐rich. The largest fraction of variability (38%) in the number of species is accounted for by the combined effect of the three groups of explanatory variables. The spatially structured climate component explains 21% of variation, while the pure climate and pure spatial components explain 14% and 11%, respectively. The effect of topography was negligible. Conclusions Delimiting the adequately inventoried areas and elaborating forecasting models using simple environmental variables can rapidly produce an estimate of the species richness distribution. Scarabaeidae species richness distribution seems to be mainly influenced by temperature. Minimum mean temperature is the most influential variable on a local scale, while maximum and mean temperature are the most important spatially structured variables. We suggest that species richness variation is mainly conditioned by the failure of many species to go beyond determined temperature range limits.     

Determinant variables of Iberian Peninsula Aphodiinae diversity (Coleoptera, Scarabaeoidea, Aphodiidae)

Aim The aims of this paper are to examine diversity–variability patterns for species of Aphodiinae (Coleoptera, Scarabaeoidea, Aphodiidae) on the Iberian Peninsula, and to determine the factors that influence their geographic distribution. Location Iberian Peninsula (Spain and Portugal). Methods Data from 30 studies and their bibliographies on species of Iberian Peninsula Aphodiinae were compiled. The reliability of the inventories was evaluated using parametric species richness estimators. In addition, a further 11 variables related to rarity, geographic distribution, or phylogenetic diversity were considered. Diversity variables were analysed using principal components analysis to reduce the number of dependent variables. Subsequently, the effect of differences in locality size among the 30 studies was eliminated by calculating and retaining the residuals of the curvilinear relationship of each diversity variable with the area. Generalized linear models were used to examine the relationships between diversity and 17 environmental variables. The diversity variables and their residuals were also subject to trend surface analysis in order to identify the relevance of spatially structured variables that had not been considered. The contribution of explanatory variables was determined through hierarchical variance analysis. Results Principal components analysis of biodiversity variables revealed that most of the variability could be explained using three biodiversity indexes: BI1, correlated positively with species richness, widely distributed species, frequent species, abundant species, species occurring in North Africa, Europe and the Iberian Peninsula, and phylogenetic diversity; BI2, correlated positively with numbers of infrequent and African–Iberian species; and, BI3, correlated positively with numbers of endemic, non‐abundant, European, and Iberian‐restricted species. A latitudinal disjunction emerged in BI1, with maximum scores at the north‐western and southern corners, while maximum BI2 scores were found throughout the south, and maximum BI3 scores in the north‐west. For BI1, it was climate that had the greatest influence, followed by lithology, and livestock presence. Geographic variables were the most significant for BI2, followed by climate and livestock presence. Finally, for BI3, climate variables were the most important, while geography, lithology and livestock presence had some relevance. Main conclusions The relevance of geographic variables indicates that other unaccounted‐for factors that are spatially structured could possibly explain additional variation in Aphodiinae diversity. These factors may be historic in nature, relating to the species groups, namely the Ibero‐European and the Mediterranean or Afro‐Iberian. The northern pattern could reflect the fact that the Iberian Peninsula acted as a colonization route and as a refuge during the glacial/interglacial cycles, while the southern pattern could be a consequence of the connection between the Iberian Peninsula and North Africa during the Messinian crisis, and/or a historic relationship in common, related to human activity.     

New or interesting Laboulbeniales (Ascomycetes) on Japanese chlaeniine beetles (Coleoptera,Carabidae)

Four species ofLaboulbenia were isolated from Japanese chlaeniines and are reported.Laboulbenia habui is described as a new species; it is possibly related toL. fasciculata. Laboulbenia habui is characterized by the proliferation and division of cell V, resulting in the formation of an obliquely superposed series of cells from which short, cylindrical cells arise in a double row, whereas there is a single row of cubical cells inL. fasciculata. Laboulbenia humilis is new for the Japanese mycoflora; antheridia of this fungus were observed for the first time; shape of the perithecial apex, persistent antheridia and the spore size suggest thatL. humilis is not closely related toL. exigua and its related taxa. ForL. proliferans andL. fasciculata, new chlaeniine hosts are listed and some supplemental notes are given.     

Quantifying the distribution and morphological variation of the beetles Homocopris achamas and Uroxys coarctatus in Andean ecosystems of Colombia

Insects that inhabit high-altitude ecosystems are an ecologically specialized group whose distribution is restricted by the presence of biogeographical barriers. These biogeographical constraints are thought to mould the shape of some insect structures because of environmental pressures that may produce better adaptations in extreme environments. We evaluated the potential distribution of Homocopris achamas and Uroxys coarctatus in two life regions (the Andean region and the Páramo region) found in the Andes of Colombia, and we determined if there were differences in their morphology along an elevational gradient. To determine the potential distribution of the species, we obtained geographical data through the systematic search of databases and entomological collections that we modelled under the maximum entropy model. We then evaluated the morphological variations by measuring geometric structures such as the clypeus (MC), the eye (ME) and the area of the anterior tibia (TA). We found that both species along the entire gradient exhibited the following characteristics: H. achamas was dominant in the Páramo region and showed two population nuclei separated by a wide biogeographic barrier, while U. coarctatus was more dominant in the Andean region and was distributed only in the northern Andes. Both were always linked to ecosystems with open vegetation that was both natural or intervened. H. achamas did not show changes in the shape of the structures while U. coarctatus showed differences in MC and ME. We suggested that livestock activity could act as an engine for breaking down biogeographical barriers allowing the distribution of a species to expand, and with this distributional expansion changes in the morphological structures of some species linked to their phenotypic plasticity could be promoted.     

Ground beetles (Coleoptera: Carabidae) as bioindicators

One of the primary goals of research on bioindicators is to identifyspecies or other taxonomic units that would reliably indicate disturbances inthe environment, and reflect the responses of other species or the overallbiodiversity. However, there is no perfect bioindicator and selecting the mostsuitable one depends to a great extent on the goal of the survey. In this paperwe examine the suitability of carabids as bioindicators. Carabids are frequentlyused to indicate habitat alteration. They have been used in grasslands andboreal forests where species number and/or abundances have been noted to changealong a habitat disturbance gradient. A common trend is that large, poorlydispersing specialist species decrease with increased disturbance while smallgeneralist species with good dispersal ability increase. Some species are notaffected by moderate disturbance. There is, however, not enough research todetermine how suitable carabids are for biodiversity studies, or how well theyrepresent the response of other species. We conclude that carabids are usefulbioindicators, but as crucial understanding of their relationship with otherspecies is incomplete, they should be used with caution.     

Lamellicorn Beetles (Coleoptera,Scarabaeoidea) of Manchuria (China): Fauna,Ecology, and Zoogeography

The species composition and taxonomic structure of lamellicorn beetles of Northeast China are considered. A total of 317 species from 86 genera, 42 tribes, 18 subfamilies, and 6 families are known to occur in the fauna of Manchuria. Seven species are recorded from China for the first time: Trox scaber (Linnaeus, 1767), Glyptotrox ineptus (Balthasar, 1931), Aegialia (Psammoporus) kamtschatica Motschulsky, 1860, Aphodius (Acrossus) superatratus Nomura et Nakane, 1951, Aphodius (Chilothorax) grafi Reitter, 1901, Maladera spissigrada (Brenske, 1897), and Valgus hemipterus hemipterus (Linnaeus, 1758); in addition, 18 species are recorded as new to the fauna of Manchuria. Among 177, 219, 208 and 226 species recorded from the Manchurian part of Inner Mongolia, Heilongjiang, Jilin, and Liaoning, 20, 29, 14 and 19 species are new to the region, respectively. The ecological and zoogeographical features of Scarabaeoidea in Manchuria are analyzed. Data on the trophic structure, phenology, and distribution of all the taxa are presented.     

转植酸酶基因玉米对步甲群落动态的影响

本研究以陷阱法研究转植酸酶基因玉米及其亲本玉米在整个生长季节对地表步甲类群的影响。每个玉米品系设置6块样地, 两个玉米品系交替排列, 每个样地设置2个采样点, 共设置24个样点, 整个玉米生育期取样8次。本研究共采集步甲标本8 012头, 隶属于11属23种, 其中黄斑青步甲Chlaenius micans个体数量分别占个体总数的87.54%, 为玉米田内的主要常见物种, 蠋步甲Dolichus halensis、 后斑青步甲Chlaenius posticalis和单齿蝼步甲Scarites terricola个体数量分别占除黄斑青步甲之外所有步甲个体总数的34.77%, 31.16%和6.21%, 这些物种组成当地玉米田内的常见物种。步甲物种多样性与常见物种个体数量随季节变化明显, 且转植酸酶基因玉米与其亲本玉米田内步甲物种多样性和常见物种个体数量的季节变化趋势相似度较高。重复测量方差分析（Repeated ANOVA）结果表明, 转植酸酶基因玉米对步甲物种丰富度、 物种多度、 香农威纳多样性指数和均匀度指数均没有显著影响; 转植酸酶基因玉米田内的后斑青步甲个体数量明显增加, 但其他常见物种没有显著变化。基于非度量多维度（NMDS）的群落结构分析表明转植酸酶基因玉米与亲本玉米田内的步甲群落结构非常相似。本文结果表明转植酸酶基因玉米的种植对步甲物种多样性及常见物种没有明显影响。     

Proventricular trituration in adult carabid beetles (Coleoptera: Carabidae)

Adult carabids that ingest particles of food have a muscular proventriculus lined internally with an intima that bears sclerotized projections. In experiments where six species of carabid were allowed to feed upon Drosophila, the average size of cuticular remains found in post-proventricular regions of the gut was generally significantly smaller than those in the crop. This reduction in size of cuticular particles is likely to be due to proventricular trituration rather than prolonged exposure to digestive secretions. There is no evidence that material is triturated by the proventriculus and returned to the crop, the main seat of digestion in carabids, so proventricular trituration is unlikely to enhance digestion. By crushing large, potentially abrasive, cuticular particles, the proventriculus may serve to protect midgut epithelial tissue.     

Distribution and microhabitats of native and non-native gammarids (Amphipoda, Crustacea) in Brittany, with particular reference to the endangered endemic sub-species Gammarus duebeni celticus

Aim  To assess temporal changes in gammarid distribution in Brittany and microhabitat-use overlap between the endangered endemic Gammarus duebeni celticus Stock & Pinkster, 1970 , the expanding natives G. pulex (Linnaeus, 1758) and Echinogammarus berilloni (Catta, 1878), and the introduced G. tigrinus Sexton, 1939.
Location  Brittany and adjacent regions in western France.
Methods  The spatial and temporal patterns in distribution of gammarids at the scale of Brittany were studied using 351 sites. Longitudinal distributions (from the source to the estuary of the river) and microhabitat-use (substratum type and water velocity) were also considered in selected rivers.
Results  At the regional scale, all species occurred together less often than expected statistically, with significant deviations from expected for G. pulex vs. both G. duebeni celticus and G. tigrinus , and for E. berilloni vs. both G. duebeni celticus and G. tigrinus . However, at the microhabitat scale, E. berilloni occurred significantly more often than expected with the endemic G. duebeni celticus , and this appears to be due to similar substratum and water velocity preferences, although at both the regional and microhabitat scales E. berilloni prefers wider streams than G. duebeni celticus . This study reveals a decline in the endangered G. duebeni celticus since 1970.
Main conclusions  The longitudinal and local distributions of G. duebeni celticus , and the higher-than-expected co-occurrence of the species with G. pulex , suggest that the decline of the endemic species may be due to changes in the environment and/or interference from native G. pulex , which is expanding its range in Brittany. The results are discussed as regards to the consequences for regional biodiversity.     

The ground beetles (Coleoptera: Carabidae) of exposed riverine sediments in Scotland and northern England

A survey of invertebrates on exposed riverine sediments (ERS) in four catchments of rivers in Scotland and northern England was carried out in 1996 and 1997 using pitfall traps. The resulting 179 lists of ground beetle species were used in ordination and classification analyses to determine the different types of habitats and the environmental factors influencing species assemblage distribution. Types of ERS habitat differed between highland and lowland catchments; there were also different numbers of habitat types in each catchment. The distribution of ERS within catchments was related to geology, position in catchment, sediment composition and the amount of vegetation. Evidence of the positive nature of river engineering was identified and the role of river management is discussed. The numbers of nationally rare and scarce ground beetle species recorded from the ERS habitats in each catchment are reported and the factors affecting their distribution discussed.     

The influence of matrix and edges on species richness patterns of ground beetles (Coleoptera: Carabidae) in habitat islands

Aim The aim of this study was to analyse whether, and how, the inclusion of habitat specialists and edge‐preferring species modifies the species–area relationship predictions of the island biogeography theory for an insect group (ground beetles, Coloptera: Carabidae) living in natural fragments. Species–habitat island area relationships applied to terrestrial habitat islands can be distorted by the indiscriminate inclusion of all species occurring in the fragments. Matrices surrounding terrestrial habitat fragments can provide colonists that do not necessarily distinguish the fragment from the matrix and can survive and reproduce there. Edge‐preferring species can further distort the expected relationship, as smaller fragments have larger edge:core ratios. Location Nineteen forest fragments were studied in the Bereg Plain, Hungary, and SW Ukraine. This area contains natural forest patches, mainly of oak and hornbeam, and supports a mountain entomofauna. Methods Ground beetles (Carabidae) present in the 19 forest patches were categorized into generalists, forest specialists and edge‐preferring species. We analysed the relationship between species richness and fragment area using species richness in the different categories. Results The assemblages contained a high share of generalist species (species that occur also in the surrounding matrix). Forest patch size and the number of generalist species showed a marginally significant negative relationship, indicating that generalist species were more important in smaller patches. Forest specialist species richness was correlated positively with patch area. Edge‐preferring species were shown to influence the species–area relationship: the number of edge‐preferring species increased with the edge:area ratio. Main conclusions Both generalist and edge‐preferring species can considerably distort the species–area relationship. Island biogeography theory can be applied to habitat islands only if the habitat islands are defined correctly from the viewpoint of the target species.     

Global diversity of water beetles (Coleoptera) in freshwater

The global diversity of True Water Beetles, False Water Beetles and Phytophilous Water Beetles (sensu Jäch, 1998a. In Jäch &; Ji (eds), Water Beetles of China, Vol. II. Zoologisch-Botanische Gesellschaft in Österreich and Wiener Coleopterologenverein, Wien: 25–42.) is assessed. Facultative Water Beetles, Parasitic Water Beetles and Shore Beetles (sensu Jäch, 1998a. In Jäch &; Ji (eds), Water Beetles of China, Vol. II. Zoologisch-Botanische Gesellschaft in Österreich and Wiener Coleopterologenverein, Wien: 25–42.) are here classified as “paraquatic” and are thus not included in the assessment. It is estimated that about 18,000 species of aquatic Coleoptera are roaming the earth at present. About 12,600 (70%) of these are already described (deadline: October 2005). About 30 beetle families have aquatic representatives, and in 25 of these families at least 50% of the species are to be considered as aquatic. Six families are supposed to include 1,000 or more aquatic species: Dytiscidae (3,908 described species/5,000 estimated), Hydraenidae (1,380/2,500), Hydrophilidae (1,800/2,320), Elmidae (1,330/1,850), Scirtidae (900/1,700) and Gyrinidae (750/1,000). Scirtidae and Hydraenidae are regarded as the least explored families, the number of described species in each of these two families probably will be almost doubled in the future. The Palearctic (ca. 3,350 described species/ca. 3,900 estimated), the Neotropical (2,510/3,900) and the Afrotropical Region (2,700/3,750) harbour almost the same number of water beetle species, followed by the Oriental (2,200/3,580) and the Australian/Pacific Realm (1,340/2,100). The Nearctic (1,420/1,550) is by far the poorest region in terms of water beetle diversity.     

Taxonomic review of Agraphydrus from Japan (Coleoptera: Hydrophilidae: Acidocerinae)

The Japanese species of the genus Agraphydrus are revised. Five species are recognized, including Agraphydrus ogatai sp. nov. from Honshu, Shikoku and Kyushu. The new species can be distinguished by the coarse ground punctures on the pronotum and elytra, and by the shape of parameres. All species except A. luteilateralis are redescribed. All species are diagnosed, relevant morphological characters are illustrated, distributional records are summarized and an updated key is provided.