Toward an inordinate fondness for stars,beetles and Lobophora? Species diversity of the genus Lobophora (Dictyotales,Phaeophyceae) in New Caledonia

Until the recent use of molecular markers, species diversity of Lobophora, an ecologically important brown algal genus with a worldwide distribution in temperate and tropical seas, has been critically underestimated. Using a DNA‐based taxonomic approach, we re‐examined diversity of the genus from New Caledonia in the Southwest Pacific Ocean. First, species were delineated using general mixed Yule coalescent‐based and barcoding gap approaches applied to a mitochondrial cox3 data set. Results were subsequently confirmed using chloroplast psbA and rbcL data sets. Species delimitation analyses agreed well across markers and delimitation algorithms, with the barcoding gap approach being slightly more conservative. Analyses of the cox3 data set resulted in 31–39 molecular operational taxonomic units (MOTUs), four of which are previously described species (L. asiatica, L. crassa, L. nigrescens s.l., L. pachyventera). Of the remaining MOTUs for which we obtained a representative number of sequences and results are corroborated across analyses and genes, we described 10 species de novo: L. abaculusa, L. abscondita, L. densa, L. dimorpha, L. gibbera, L. hederacea, L. monticola, L. petila, L. rosacea, and L. undulata. Our study presents an excellent case of how a traditional morphology‐based taxonomy fails to provide accurate estimates of algal diversity. Furthermore, the level of Lobophora diversity unveiled from a single locality in the Pacific Ocean raises important questions with respect to the global diversity of the genus, the distributions and range sizes of the individual species, as well as the mechanisms facilitating coexistence.     

Assemblages of carabid beetles (Coleoptera, Carabidae) in humid forest habitats of different stages of succession in the Puszcza Knyszyńska Forest (northeastern Poland)

During a period of three years (2006-2008) the carabid fauna in wet and humid forest habitats of different stages of succession was studied at the Puszcza Knyszynska (north-east part of Poland). The aim of this study was to determine how the assemblages of the carabid fauna change in relation to the ongoing process of succession. Using pitfall traps, 24 plots were sampled. The plots were located in stands of different age, from two year old plantations to more than 100 year old forests. Additionally, the stands were ordered in three moisture classes (wet, humid and very humid) and two classes of soil richness. As indicators for change in the carabid fauna in relation to age of the stands Mean Individual Biomass (MIB), species diversity and share of forest species were used. By applying multivariate statistics the relation of the different habitat characteristics to changes in the carabid fauna was examined. During the study 8903 individuals belonging to 57 species were collected. Pterostichus niger represented 28% of the total catches and therefore the most common species. Another common species, Pterostichus melanarius, contributed to 13% of the total catch. This species was caught at every plot, even in the old forests. In contrast to the results obtained by Szyszko (1990) for fresh and dry pine stands, in this study the relation of MIB with the age of forest was not significant. Although the number of species was rather constant, the number of individuals belonging to the group of forest species significantly increased with the ageing of the forest. The multivariate analysis showed a relationship with ageing of the stands and soil richness rather than with moisture and size of the forest. According to the present paper, clear cuttings in wet and humid habitats do not cause a strong degradation of the carabid fauna.     

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.     

Local-scale distribution of cholevid beetles (Col., Leiodidae: Cholevinae) in the province of León (Spain)

Ecological correlates of the distribution of nine common leiodid species were studied in three river valleys on the southern side of the Cantabrian Range in León, in northern Spain. Soil moisture content, substrate temperature variability and type of organic matter proved to be the key factors determining the distribution of species of this group. These factors may have important effects not only at the local level but also on the medium scale.     

How labile are the egg‐laying preferences of seed beetles?

Abstract.  1. Previous studies have produced conflicting results with respect to the genetic lability of host preference in the seed beetle Callosobruchus maculatus .
2. In this study, replicate lines of an Asian population were kept on an ancestral host (mung bean) or switched to a novel host (cowpea). After 40+ generations, lines were assayed for host preference (in choice tests) and host acceptance (under no-choice conditions), and were compared to African lines chronically associated with cowpea.
3. Host preference diverged in the expected direction. When presented a mixture of cowpeas and mung beans, females from the cowpea lines laid a greater fraction of their eggs on cowpea than did females from the mung bean lines. Preference for cowpea was nearly as strong in the cowpea lines as it was in the cowpea-adapted African lines.
4. In contrast, the experimental host shift did not affect long-term host acceptance. African females laid more eggs if given cowpeas than if given mung beans, but realised fecundities in the cowpea and mung bean lines were similar on the two hosts. Females from all lines laid more eggs if they were reared on cowpea than on mung bean, but rearing host had no effect on either relative host acceptance or host preference.
5. Comparisons with earlier studies suggest that the lability of host preference varies among beetle populations, which precludes generalisation at the species level. Because lines were maintained under no-choice conditions, modification of host preference probably occurred via a lower acceptance threshold for the novel host, without a concomitant change in the long-term acceptance of the ancestral host.     

Useful model organisms,indicators, or both? Ground beetles (Coleoptera,Carabidae) reflecting environmental conditions

Classic studies have successfully linked single-species abundances, life-history traits, assemblage structures and biomass of carabid beetles to past and present, human-caused environmental impacts and variation in ‘natural’ conditions. This evidence has led many to suggest carabids to function as ‘indicators’ − a term that bears multiple meanings. Here, a conservation-oriented definition for an indicator is used, carabid indicator potential from seven views is evaluated, and ways to proceed in indicator research are discussed. (1) Carabid species richness poorly indicates the richness and abundance of other taxa, which underlines the importance of using multiple taxa in environmental assessments. The ability of assemblage indices and specialist or functional-group abundances to reflect rare species and habitats should be examined in detail. (2) Experimental evidence suggests that carabids may potentially serve as keystone indicators. (3) Carabids are sensitive to human-altered abiotic conditions, such as pesticide use in agro-ecosystems and heavy metal contamination of soils. Carabids might thus reflect ecological sustainability and ‘ecosystem health’. (4) Carabid assemblages host abundant species characteristic of particular habitat types or successional stages, which makes them promising dominance indicators. (5) Carabids reflect variation in ‘natural’ conditions, but vegetation and structural features are more commonly adopted as condition indicators. Carabids nevertheless provide yet another, equally accurate, view on the structure of the environment. (6) Carabids may function as early-warning signalers, as suggested by recent studies linking climate and carabid distributions. (7) Carabids reflect natural and human-caused disturbances and management, but the usefulness of these responses for conservation purposes requires further research. In summary, European carabids appear useful model organisms and possibly indicators because they are diverse, taxonomically and ecologically well-known, efficiently reflect biotic and abiotic conditions, are relevant at multiple spatial scales, and are easy to collect in sufficiently large numbers to allow statistical analyses. The assumption that carabid responses would reflect rare environmental conditions or the responses of rare and threatened species ‒ crucial information for conservationists and managers ‒ has not yet been critically evaluated. Even if it holds, the usefulness will be context dependent: species and their populations vary, conditions vary, questions put forward vary, and assessment goals vary.     

External morphology of the male and female of Sphyrion lumpi (Krøyer,1845) (Copepoda; Siphonostomatoida; Sphyriidae)

Sphyrion lumpi is a sexually dimorphic, parasitic copepod which causes significant losses in fisheries in the North Atlantic. Studies involving both light and scanning electron microscopy revealed important details of the external morphology of both sexes that are discussed in relation to other members of the family Sphyriidae. Conclusions are drawn regarding the life cycle of S. lumpi. The present finding of this parasite on Urophycis tenuis constitutes a new host record.     

Phoresy of Trichouropoda shcherbakae Hirschmann, 1972 (Acari: Mesostigmata) on beetles of the genus Tetropium Kirby, 1837 (Coleoptera: Cerambycidae) in Białowieża Forest, Poland

The aim of this study was to assess the phoretic relationship between two beetle species of the genus Tetropium and mites from order Mesostigmata. The study was conducted in the Bia?owie?a Forest, which is recognized as one of Europe’s last natural forest areas. Insects were caught over a period of 8 weeks in 72 attractant traps (type Intercept IPM). In total 1250 specimens of genus Tetropium were collected. We analyzed 524 beetles, including 295 specimens of T. castaneum and 229 specimens of T. fuscum. On 49 beetles (9.4%) there were 785 individuals of Trichouropoda shcherbakae (Trematuridae). Mites were more common on T. fuscum, which carried 82% of all collected deutonymphs. Most of the mites found on beetles were attached to their legs. This study reports on changes in the intensity of phoresy in time and location of mite deutonymphs on their host species.     

Assemblage structure and altitudinal distribution of lady beetles (Coleoptera,Coccinellidae) in the mountain spruce forests of Pol’ana Mountains,the West Carpathians

In two successive years we recorded a total of 3,636 individuals and 17 species of adult lady beetles (Coleoptera, Coccinellidae) in the spruce forests of Pol’ana Mts (the West Carpathians) at altitudes ranging from 600 m to 1,300 m a.s.l. Four lady beetle species were documented as predominating (dominance of abundance > 5%) over the study period. They were the following: Aphidecta obliterata (1,828 individuals and 50.3%), Coccinella septempunctata (634 individuals and 17.4%), Adalia conglomerata (594 individuals and 16.3%) and Anatis ocellata (279 individuals and 7.7%). The assemblages of lady beetles differed among the areas and also between the years. The season revealed neglegible effect on distribution of lady beetles, whereas the effect of altitude was more pronounced. A. conglomerata preferred the areas at lower altitude (600–725 m) to those at middle (900–925 m) and/or upper altitude (1,250–1,300 m). In contrast, A. obliterata and C. septempuctata were most abundant in the area at middle altitude. The altitudinal location of area partly explained the variability in abundance of lady beetles. The first ordination axis constructed by means of correspondence analysis (CA) represented an altitudinal gradient and accounted for 19.4% of the total variance of the species data. The great proportion of lady beetle species not typically associated with spruce and/or other coniferous trees than spruce (70.6%, n = 17) may be explained by an ecotonal effect.     

Contributions to the knowledge of subterranean trechine beetles in southern China’s karsts: five new genera (Insecta,Coleoptera, Carabidae,Trechinae)

Recent discoveries reveal that southern China’s karsts hold the most diverse and morphologically modified subterranean trechine beetles in the world, albeit the first troglobitic blind beetle was only reported in the early 1990’s. In total, 110 species belonging to 43 genera of cavernicolous trechines have hitherto been recorded from the karsts of southern China, including the following five new genera proposed below: Shiqianaphaenops Tian, gen. n., to contain two species: Shiqianaphaenops majusculus (Uéno, 1999) (= Shenaphaenops majusculus Uéno, 1999, comb. n.), the type species from Cave Feng Dong, Shiqian, Guizhou, and Shiqianaphaenops cursor (Uéno, 1999) (= Shenaphaenops cursor Uéno, 1999, comb. n.), from Cave Shenxian Dong, Shiqian, Guizhou; and the monotypic Dianotrechus Tian, gen. n. (the type species: Dianotrechus gueorguievi Tian, sp. n., from Cave Dashi Dong, Kunming, Yunnan), Tianeotrechus Tian & Tang, gen. n. (the type species: Tianeotrechus trisetosus Tian & Tang, sp. n., from Cave Bahao Dong, Tian’e County, Guangxi), Huoyanodytes Tian & Huang, gen. n. (the type species: Huoyanodytes tujiaphilus Tian & Huang, sp. n., from Longshan, Hunan) and Wanhuaphaenops Tian & Wang, gen. n. (the type species: Wanhuaphaenops zhangi Tian & Wang, sp. n., from Cave Songjia Dong, Chenzhou, Hunan).     

Metabolism and cold tolerance of overwintering adult mountain pine beetles (Dendroctonus ponderosae): Evidence of facultative diapause?

We sought evidence for a distinct diapause in adult overwintering mountain pine beetles (Dendroctonus ponderosae Hopkins) by measuring metabolic rate and supercooling ability of field collected beetles throughout the year. Metabolic rates measured at 0, 5, and 10°C declined significantly from October through November, then rose slowly, reaching levels as high as those recorded in October by late May. From December to February metabolic rates were not correlated with minimum weekly phloem temperatures (R(2)=0.0%, P=0.592), but were correlated with phloem temperatures as winter advanced to spring (R(2)=44.8%, P=0.010), a pattern consistent with progression through the maintenance and termination phases of diapause. Supercooling points were also significantly lower in winter compared to fall and spring (F((8,143))=32.6, P<0.001) and were closely correlated with metabolic rates (R(2)>79% for all three temperatures). Dry mass declined linearly with winter progression (F((8,150))=8.34, P<0.001), explained by catabolism of metabolic reserves, with a concomitant accumulation of metabolic water (F((8,147))=35.24, P<0.001). The strong mid-winter metabolic suppression correlated with improved supercooling ability, coupled with their lack of response to variation in environmental temperature, are evidence of possible diapause in adult overwintering mountain pine beetles.     

Does wing morphology affect recolonization of restored farmland by ground‐dwelling beetles?

Revegetation of previously cleared land is widely used to increase habitat area and connectivity of remnant vegetation for biodiversity conservation. Whether new habitat attracts or supports fauna depends on the dispersal traits of those fauna as well as the structure and composition of the surrounding landscape. Here, we examined wing morphology as a key dispersal trait for beetles in a revegetated landscape and asked, first, how it was related to phylogeny (family), trophic position, and body size. Second, we asked if wing morphology of recolonizing (or persisting) beetles varied with habitat characteristics at multiple scales, from microhabitat to landscape context. Third, we examined how common winged and wingless species responded to habitat at multiple scales. We measured the wing morphology of ground‐dwelling beetles from a restoration chronosequence, including paddocks, “young” revegetation (8–11 years old), “old” revegetation (14–19 years old), and fenced remnant vegetation. We found that body size and family membership were significant predictors of winglessness, with wingless species of carabids and curculionids being larger than their winged counterparts. We found no difference in the number of sites occupied by winged and wingless species, and no relationship between the wing morphology traits represented in different locations and habitat characteristics or landscape context. Furthermore, the most abundant species of both winged and wingless ground‐dwelling beetles had relatively little affinity to any habitat successional stage. Thus, despite intrinsic differences in wing morphology among species of ground‐dwelling beetle, we found no evidence that flight‐related dispersal limitations influenced recolonization (or persistence) in this landscape.     

The role of moose <Emphasis Type="Italic">Alces alces</Emphasis> L. in boreal forest – the effect on ground beetles (Coleoptera,Carabidae) abundance and diversity

The indirect effect of moose Alces alces browsing on ground beetle's abundance and diversity was investigated by pitfall trapping in a mixed coniferous forest in Vestfold County (59°19′ N, 9°50′ E, Norway), during the summer of 2002. Three areas with different browsing pressures, ranging from non- to medium- and heavily browsed were chosen and dry weight of bilberry Vaccinium myrtillus and humidity at ground level were measured in the three locations. As predicted, the gradient analyses showed that browsing by moose influenced the composition of carabid fauna, and that browsing intensity and humidity covaried with the most important gradient in carabid species composition found across the three locations. Species that live in light stands with rather dry soil, were more often captured in the browsed areas, whereas shade tolerant and hygrophilous species were more abundant in the non-browsed area. The carabid abundance increased significantly with increasing browsing pressure. According to our predictions, the diversity at trap level (α-diversity) was higher in the highly browsed area. Conversely, species turnover (β-diversity) decreased with browsing intensity. On the other hand, the rarefaction analysis showed that the regional species richness (γ-diversity) was considerably higher in the medium browsed area than in the heavily browsed one, which is consistent with the intermediate disturbance hypothesis. This study indicates that moose, by reducing the bilberry that constitutes the field layer in summer, affect carabid species composition and might be capable to reshape the whole ecosystem in our study area by a cascade effect.     

Do male mealworm beetles, <Emphasis Type="Italic">Tenebrio molitor</Emphasis>, sustain the honesty of pheromone signals under immune challenge?

Immune function is potentially costly and traded-off against the expression of sexual signals, thus, making sexual advertisement a condition-dependent and honest indicator of current immunocompetence. We conducted a series of laboratory experiments using mature mealworm beetles, Tenebrio molitor, to examine whether an immunological challenge (nylon implant(s), microbial lipopolysacharides, microlatex beads) could affect the attractiveness of male pheromones or male’s survival in ad libitum and ‘water-only’ food regimes or whether pheromones signal more long-term qualities of males. We treated another set of newly-emerged males with a single nylon implant and gave first ad libitum food but later only water. We used several immune challengers and feeding regimes to examine if the expected trade-off between immune function and sexual signaling would be expressed differently depending on the resource level and the type of the immune challenge. None of the treatments affected the female preference for male pheromones or the male longevity except for the acute mortality caused by two-implant treatments. However, males lost less body mass when immune challenged and given an opportunity to feed. We conclude that females seem to prefer certain males, and the effect of immune challenge in males cannot systematically override these preferences.     

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.     

Species-specific use of allochthonous resources by ground beetles (Carabidae) at a river–land interface

A variety of organisms mediate river–terrestrial linkages through spatial subsidies. However, most empirical studies have classified organisms rather broadly (e.g., by functional group or taxonomic family) and have dismissed species-level linkages at the interface of ecosystems. Here, we show how allochthonous resource use varies among taxonomically similar species of ground beetles (family Carabidae) across seasons (June–September). We investigated seasonal shifts in the distribution of five beetle species and their dietary responses to spatial subsidies (emerging aquatic insects) in a Japanese braided river. Despite their taxonomic closeness, the ground beetles showed species-specific responses to spatial subsidies, and beetle distribution patterns tended to coincide with their diets. Overall, 1–56% of ground beetle diets were derived from aquatic prey. One genus (Bembidion spp.) mainly consumed aquatic prey, while three species fed primarily on terrestrial prey across all seasons. However, one species (Lithochlaenius noguchii) showed shifts in its diet from aquatic to terrestrial prey according to subsidy availability. The observed variation in allochthonous resource use was likely related to species-specific foraging modes, physiological tolerance to dry conditions, and interspecific competition. Our findings suggest that considering species-specific interactions is necessary to fully understand cross-system interactions and recipient food-web dynamics.