How long can insect species exist? Evidence from extant and fossil Micromalthus beetles (Insecta: Coleoptera)

Six new fossils of Micromalthus (Coleoptera: Archostemata) from Dominican amber are compared with extant and previously described fossil micromalthid beetles. The amber inclusions are well preserved and all important morphological features are visible. Taking into account the morphological variability of the extant species Micromalthus debilis LeConte, 1878 , it is not possible to find any morphological features that distinguish the fossils from the extant species. This also applies to the Dominican amber inclusion described as Micromalthus anasi Perkovsky, 2008, which therefore is considered a junior synonym of M. debilis. The lack of morphological change in M. debilis over time might possibly be explained by unusually stable environmental conditions, as this species occupies a very specialized ecological niche in decaying timber. A general survey of fossil insects indistinguishable from extant species is presented. © 2009 The Linnean Society of London, Zoological Journal of the Linnean Society, 2010, 158 , 300–311.     

Is it possible to distinguish alien species of beetles (Coleoptera) from native ones?

Species established outside their native ranges are termed alien. Biological invasions of beetles are poorly studied. Distinguishing between alien and native species is necessary for conservation as well as for taxonomic, zoogeographic, and evolutionary studies. It constitutes a difficult problem, but the experience of botany and some branches of zoology gives reasons to believe that it is not unsolvable. The following criteria for distinguishing alien beetle species from native ones are proposed based on the criteria developed for plants, algae, mammals, and marine invertebrates: (1) detection of an established population of the species which has not been recorded earlier in the region; (2) disjunction of the range which cannot be explained by disjunction of suitable landscapes or host plant ranges; (3) expansion of a part of the range isolated from its main part; (4) highly localized distribution in an area adjacent to a known invasion pathway; (5) establishment in other regions; (6) dependency on another non-native species (feeding on an alien host plant or animal); (7) absence of specific parasites in the given region and their presence in some other region; (8) association with anthropogenic biotopes; (9) sharp fluctuations of abundance; (10) lack of taxonomically close species in the given region and their presence in other regions; (11) detection in the region of two or more taxonomically and/or ecologically close species typical of another region; (12) presence of known vectors of invasion; (13) low genetic diversity; (14) reproduction by parthenogenesis or inbreeding. These criteria are mere indirect evidences of the alien status of a species in the given territory, because numerous exceptions exist. Usually it is impossible to recognize an alien species by a single criterion, but matching several criteria characterizes the species as an alien one with high probability.     

From plains to inselbergs: species in special habitats as indicators for climate change?

Aim This study proposes a process to select plant species that would provide suitable candidates for monitoring climate change impacts in areas where complete biological inventories are lacking. Location Inselberg floras of nine inselberg landscapes (i.e. isolated mountains) in the arid Desert and Nama Karoo biome in Namibia were analysed to develop a selection process. Methods Data from detailed field surveys were summarized to determine species only occurring on inselberg habitats (i.e. inselberg specialists). Detrended correspondence analysis and a step‐by‐step selection process based on species distribution patterns were used to determine species occurring on inselbergs beyond their zonal distribution ranges. Results The systematic selection process initially identified 88 plant species. Based on field observations and published sources eliminating species (1) with a wide distribution elsewhere, (2) distribution influenced by local effects and (3) for which their status of knowledge of distribution was clearly inadequate, this list was further reduced to 25 species. This included southern species occurring on inselbergs likely beyond their zonal distribution, such as Adenolobus garipensis, Aloe dichotoma and Euphorbia gummifera, as well as savanna and escarpment species at their western zonal distribution edge (e.g. Cordia sinensis, Commiphora glaucescens and Moringa ovalifolia). Main conclusions The step‐by‐step selection process proposed in this study to assist with the selection of indicators for climate change provides an objective tool in areas where biodiversity coverage is not adequate and little is known about physiology, growth and reproductive patterns of individual species. As such it introduces a method for preliminary screening of species, but will require further input based on field observations and expert knowledge.     

How good are carabid beetles (Coleoptera,Carabidae) as indicators of invertebrate abundance and order richness?

Ground invertebrates were sampled by pitfall trapping on Brentmoor Heath, Surrey, UK during the summers of 2009 and 2010 to determine whether the abundance and species richness of carabids on bare ground patches are representative of invertebrate abundance and order richness on the same patches. Four patch sizes were investigated as well as the adjacent mown and unmown areas, and a range of environmental parameters were measured at each patch. Results show that increasing abundance and richness of carabids can give a broad indication of whether invertebrate abundance and order richness are increasing. Invertebrates in general are sensitive to a greater number of environmental variables and complex interactions than carabids are, due to the vast array of biological requirements of the large range of invertebrate species. All else being equal, smaller patches appear to benefit both carabid abundance and invertebrate abundance. Converse to the results of carabid species richness, larger patches appear to benefit invertebrate order richness. This study highlights the importance of testing the effect of habitat management strategies on a range of taxa rather than assuming the results for a bioindicator will suffice for management decisions. Whilst bioindicators may give a broad indication of effects on similar taxa, the precise nature of those effects will be determined by a number of species- and site-specific variables.     

Italian Dermestidae: notes on some species and?an?updated checklist (Coleoptera)

An up-to-date checklist of the Italian Dermestidae is provided. The presence of 95 species in Italy is confirmed, while further 5 species (Dermestes (Dermestes) vorax Motschulsky, 1860, Thorictuspilosus Peyron, 1857, T. wasmanni Reitter, 1895, Attagenus (Attagenus) simonis Reitter, 1881 and Globicornis (G.) breviclavis (Reitter, 1878)) and 1 subspecies (A. (A.) tigrinus pulcher Faldermann, 1835) are excluded from the Italian fauna.Attagenus (Attagenus) calabricus Reitter, 1881 and A. (A.) lobatus Rosenhauer, 1856 are for the first time recorded from Abruzzi and Tuscany respectively; A. (A.) silvaticus Zhantiev, 1976 is recorded for the first time from mainland Italy (Apulia); Anthrenus (Anthrenus) angustefasciatus Ganglbauer, 1904 is new to northern Italy (Friuli-Venezia Giulia), central Italy (Tuscany), Apulia and Basilicata; A. (A.) munroi Hinton, 1943 is new to central Italy (Elba Island); A. (A.) delicatus Kiesenwetter, 1851 is for the first time recorded from Apulia; Globicornis (Globicornis) fasciata (Fairmaire & Brisout de Barneville, 1859) is new to southern Italy (Basilicata); G. (Hadrotoma) sulcata (C.N.F. Brisout de Barneville, 1866) is for the first time recorded from central Italy (Abruzzi), Campania and Sicily, whileTrogoderma inclusum LeConte, 1854 is new to Apulia.Seven species (Dermestes (Dermestes) peruvianus Laporte de Castelnau, 1840, D. (Dermestinus) carnivorus Fabricius, 1775, D. (Dermestinus) hankae Háva, 1999, D. (Dermestinus) intermedius intermedius Kalík, 1951, D. (Dermestinus) szekessyi Kalík, 1950, Anthrenus (Anthrenops) coloratus Reitter, 1881 and Trogodermaangustum (Solier, 1849)) recently recorded from Italy (without further details) are discussed.The lectotype and a paralectotype are designated forAttagenus (A.) calabricus Reitter, 1881 from Calabria.Attagenus pellio (Linnaeus, 1758) var. pilosissimus Roubal, 1932 is removed from synonymy with A. (A.) pellio and recognized as a valid species (stat. prom.); it is known from Lombardy, Apulia and Calabria.     

Enhancing gardens as habitats for plant-associated invertebrates: should we plant native or exotic species?

Domestic gardens, typically consisting of a mixture of native and non-native plants, support biodiversity. The relative value of these native and non-native plants for invertebrates is largely unknown. To address this a replicated field experiment with plots planted with one of three assemblages of non-invasive perennial and shrubby garden plants (treatments), based on plant origin [UK native, near-native (Northern Hemisphere) and Exotic (Southern Hemisphere)] was established. Over 4 years the invertebrates were recorded by Vortis suction sampler and amount of plant material measured. The abundance of above ground plant-inhabiting invertebrates increased with canopy cover and was higher on the native treatment. For several functional groups including herbivores and some predatory groups the near-native plants supported only marginally fewer individuals compared to native plots, with exotic plants being less favoured. The experiment demonstrated that gardens and other cultivated ornamental plantings support a wide range of plant-inhabiting invertebrates from primary functional groups regardless of the plants’ origin and the more plant matter (canopy cover) available the greater the abundance. Greater abundance of invertebrates will be supported by gardens and cultivated planting schemes with plantings biased towards native and near-native plants and that provide dense vegetation cover. However, exotic plants should not be dismissed as these are inhabited by some invertebrates.     

Sub-cortical Coleoptera in dead pines and spruces: is primeval species composition maintained in managed forests?

The sub-cortical beetle fauna of dead Scots pine (Pinus sylvestris) and Norway spruce (Picea abies) trunks was compared in primeval forests and managed forests in central Finland. The numbers of both individuals and species were higher in the managed forest in spite of the smaller trunk surface area examined. The proportion of rare species was higher in the primeval forest. Although most species occurred both in primeval and managed forests, there were striking differences in the abundance relations: there was only one species (Pytho depressus) in common among the ten most abundant species. The proportion of bark beetles (Scolytidae) was more than 50% in the managed forests, and less than 5% in the primeval forests. The number of species per site was associated with observation date, occurrence of snails and trunk position (standing or lying) in the primeval forest, and with trunk diameter in the managed forests. The occurrence of rare beetle species in dead conifer trunks was related to man's effects on the forest. Although many sub-cortical species can live in managed forests, the fauna differs drastically from that of primeval forests.     

How to estimate carabid biomass?—an evaluation of size-weight models for ground beetles (Coleoptera: Carabidae) and perspectives for further improvement

Journal of Insect Conservation - Biomass is an important metric for monitoring carabid populations and serves as an ecological indicator. Models that predict carabid weight based on body size...     

The influence of waste pits on species composition and structure of raised bogs’ plant communities in the Middle Ob area

The technologically altered structure of raised bogs plant communities adjacent to the waste pits of the largest oil fields in the Middle Ob (middle taiga subzone) is considered. A list of vascular plants is detected; mosses are the dominant species.     

Why does grassland productivity increase with species richness? Disentangling species richness and composition with tests for overyielding and superyielding in biodiversity experiments.

The causal relationship between the biodiversity of natural and modified environments and their net primary production has been a topic of significant scientific controversy and scrutiny. Early theoretical and empirical results indicated that production was sometimes significantly correlated with species richness when species richness was directly manipulated in experimental systems. Possible mechanisms for this phenomenon include statistical sampling effects, complementary resource use and mutualistic interactions. However, the interpretation of experimental results has sometimes confounded species richness with species composition, and disentangling the effects of species diversity from species identity has proved a formidable challenge. Here, I present a statistical method that is based on simple probability models and does not rely on the species composition of individual plots to distinguish among three phenomena that occur in biodiversity-production experiments: underyielding, overyielding and (a new concept) superyielding. In some cases, distinguishing these phenomena will provide evidence for underlying mechanisms. As a proof-of-concept, I first applied this technique to a simulated dataset, indicating the strengths of the method with both clear and ambiguous cases. I then analysed data from the BIODEPTH experimental biodiversity manipulations. No evidence of either overyielding or superyielding was detected in the BIODEPTH experiment.     

Eretes diving beetles (Coleoptera: Dytiscidae) in Central Europe – witnesses of climate change?

Records of the predaceous diving beetles of the genus Eretes Laporte, 1833 (Coleoptera: Dytiscidae) in Central Europe are summarised. While old records from the beginning of the twentieth century from the Czech Republic, Hungary, and Romania belong to Eretes griseus (Fabricius, 1781), a species which has not been recaptured in Central Europe for nearly the last hundred years, recently collected specimens from Hungary and Slovakia belong to E. sticticus (Linnaeus, 1767) and represent its first records in these countries as well as in Central Europe. The first specimens were collected at light during hot summer nights and may document a recent spreading of the species from the Mediterranean. In addition, the occurrence of E. sticticus is formally confirmed in Bulgaria, Croatia, Greece, Israel, Libya, South European Territory of Russia, and Tunisia.     

Human density as an influence on species/area relationships: double jeopardy for small African reserves?

Small reserves are especially likely to lose species. Is that because the reserves are small, or because small reserves are located in especially adverse landscapes? It seems that the question has rarely, if ever, been asked. Data on reserve size and location in Africa, and calculations of local (within 50 km) mean human densities from available census records per province per country were the database here used to answer the question. IUCN grade I and II reserves in Africa are located across the range of human densities per country, including in regions of higher than average density. Furthermore reserve size correlates with local human density, such that small reserves are indeed significantly more likely than are large reserves to be located in regions of high human density (n = 169; P < 0.0001). However, while local human density correlates significantly with human-caused mortality of carnivores (the only taxon for which we had data), it does not correlate with detected extinctions in reserves in east Africa (the only region with available data). Rather, area of reserve is the main predictor. Nevertheless, abundant other evidence of the adverse effects of high human density on persistence of species and wilderness indicates that we need to take as a warning the findings reported here that small reserves occur in regions of high human density, and that human density correlates with human-caused mortality. They indicate that small reserves might face the double jeopardy of both their small size, and also their situation in especially hostile surroundings. In effect, small reserves are more isolated in more adverse habitat than current analyses in conservation biology, landscape ecology, or metapopulation analysis usually indicate.     

How does spittlebug oviposition affect shoot growth and bud production in two willow species?

We measured the effects of oviposition by the spittlebug Aphrophora pectoralis on shoot growth and bud production in two willow species, Salix miyabeana and Salix sachalinensis. In autumn, adult females of A.pectoralis insert their ovipositor into the apical region of 1-year-old shoots, resulting in the death of most shoot tips within 1week. Consequently, an increase in the number of dead buds and a decrease in the number of vegetative buds on 1-year-old shoots was recorded. In the following spring, the growth of current-year shoots was greatly increased on 1-year-old shoots damaged by spittlebug oviposition. Furthermore, spittlebug oviposition increased the production rate of vegetative buds in both S.miyabeana and S.sachalinensis. However, no impact on the production rate of reproductive buds was detected in either willow. We conclude that the compensatory growth of current-year shoots and an increase in vegetative buds in the two willow species was caused by oviposition of A.pectoralis.     

What determines a species' geographical range? Thermal biology and latitudinal range size relationships in European diving beetles (Coleoptera: Dytiscidae)

1.  The geographical range sizes of individual species vary considerably in extent, although the factors underlying this variation remain poorly understood, and could include a number of ecological and evolutionary processes. A favoured explanation for range size variation is that this result from differences in fundamental niche breadths, suggesting a key role for physiology in determining range size, although to date empirical tests of these ideas remain limited.
2.  Here we explore relationships between thermal physiology and biogeography, whilst controlling for possible differences in dispersal ability and phylogenetic relatedness, across 14 ecologically similar congeners which differ in geographical range extent; European diving beetles of the genus Deronectes Sharp (Coleoptera, Dytiscidae). Absolute upper and lower temperature tolerance and acclimatory abilities are determined for populations of each species, following acclimation in the laboratory.
3.  Absolute thermal tolerance range is the best predictor of both species' latitudinal range extent and position, differences in dispersal ability (based on wing size) apparently being less important in this group. In addition, species' northern and southern range limits are related to their tolerance of low and high temperatures respectively. In all cases, absolute temperature tolerances, rather than acclimatory abilities are the best predictors of range parameters, whilst the use of independent contrasts suggested that species' thermal acclimation abilities may also relate to biogeography, although increased acclimatory ability does not appear to be associated with increased range size.
4.  Our study is the first to provide empirical support for a relationship between thermal physiology and range size variation in widespread and restricted species, conducted using the same experimental design, within a phylogenetically and ecologically controlled framework.     

What do we know about winter active ground beetles (Coleoptera,Carabidae) in Central and Northern Europe?

This paper summarizes the current knowledge on winter active Carabidae in Central and Northern Europe. In total 73 winter active species are listed, based on literature and own observations. Ground beetles are among the three most numerous Coleoptera families active during the autumn to spring period. The winter community of Carabidae is composed both of larvae (mainly autumn breeding species) and adults, as well as of epigeic species and those inhabiting tree trunks. Supranivean fauna is characterized by lower species diversity than the subnivean fauna. The activity of ground beetles decreases in late autumn, is lowest during mid-winter and increases in early spring. Carabidae are noted as an important food source in the diet of insectivorous mammals. They are also predators, hunting small winter active invertebrates.     

Experimental effects of habitat fragmentation on rove beetles and ants: patch area or edge?

The effects of habitat fragmentation may include the loss of species from isolated fragments or changes in species abundances among habitats that differ in area, structure, or edge characteristics. We measured the species richness and abundance of ground‐dwelling insects in a 1.14‐ha old field that was mowed to produce patches of unmowed vegetation which differed in size, degree of isolation, and the amount of habitat edge. Four treatments – ranging from unfragmented (169‐m²) to highly fragmented (1‐m²) patches – were replicated four times in a Latin square design, and insects were sampled twice during 1995 using 177 pitfall traps. Species richness showed a non‐monotonic response to fragmentation, with the fewest species occurring in the slightly fragmented treatment. Responses of rove beetles and ants, the most species‐rich and abundant taxa, respectively, were similar to the overall insect community but ants had a stronger and more consistent treatment effect in both sample months. Ordinations of ant and rove‐beetle assemblages using nonmetric multidimensional scaling showed that the slightly fragmented treatment differed from other treatments in species occurrence and abundance. The lower species richness in the slightly fragmented treatment was primarily due to a subset of ant and rove beetle species that showed a lower abundance than in other treatments, possibly because this treatment had the greatest amount of habitat edge. We hypothesize that the non‐monotonic species response to fragmentation was due to the differential effects of habitat edge on species movements across the habitat boundary between unmowed patches and mowed areas. A greater effect due to the amount of habitat edge rather than total patch area, at least among the range of patch sizes studied, suggests that the length of habitat edge may be quite important to the distribution and abundance of ground‐dwelling animals in fragmented habitats.     

Orchid bees as bio-indicators for organic coffee farms in Costa Rica: does farm size affect their abundance?

The potential of Euglossini bees, especially Euglossa, as biological indicators of organic vs nonorganic coffee farms was studied in Atenas and San Isidro, Alajuela, Costa Rica using 1.8-cineole as lure. Observations were made for three days at each of four farms and complemented with data from a year of observations. Orchid bees were in greater abundance in the organic farms (t-Student test). However, lower abundances suggest that an organic farm may be negatively affected by the proximity of non-organic farms, depending on its size and distance. Orchid bees may be indicators of organic coffee farms.