The effects of body size on mating and reproduction in Brachinus lateralis (Coleoptera: Carabidae)

Abstract. 1. The causes and reproductive consequences of body size variation of Brachinus lateralis Dejean, a parasitic carabid beetle, were investigated.
2. Body size variation occurs within and between sites. Host size has a major influence on body size of the adult.
3. Fecundity is positively correlated with body size. Egg size is not correlated with body size.
4. Mating males tend to be larger than non-mating males. There is a positive correlation of body sizes in mating pairs.
5. Limited opportunity for host choice may maintain size variation despite the advantages of large size.
6. The non-random patterns of mating for a species without obvious intrasexual aggression suggest that subtle means of male-male competition or female choice may be important.     

Livestock Trampling Reduces the Conservation Value of Beetle Communities on High Quality Exposed Riverine Sediments

Exposed riverine sediments (ERS) are habitat for a large number of rare and threatened specialist species of invertebrates and are of considerable conservation importance. Livestock trampling is believed to be one of the most widespread causes of damage to ERS habitats in the UK, and as such, its effects were the focus of this investigation. Beetle density was measured at two points within 25 distinct patches of habitat along ∼ ∼47 km of the Afon Tywi special site of scientific interest in South Wales, which is known to support an extremely good quality ERS beetle fauna in a UK context. Partial canonical correspondence analyses were used to explore the relationship between beetle assemblage and a range of environmental variables. The percentage of fine (<8 mm) sediments, median sediment size, distance downstream, cattle stocking levels, and counts of sheep faeces were found to best relate to beetle abundance and assemblage structure. Species richness was positively associated with stocking levels, probably because of the addition of species associated with resultant elevated levels of silt and organic matter. The ERS quality score, which is a measure of conservation value based on the rarity of specialist ERS beetles, was negatively associated with measures of trampling damage. It was therefore concluded that livestock trampling reduces the conservation value of beetle communities on high quality ERS and management should restrict trampling in sites of high conservation importance.     

Life in harsh environments: carabid and spider trait types and functional diversity on a debris‐covered glacier and along its foreland

1. Patterns of species richness and species assemblage composition of ground‐dwelling arthropods in primary successions along glacier forelands are traditionally described using a taxonomic approach. On the other hand, the functional trait approach could ensure a better characterisation of their colonisation strategies in these types of habitat. 2. The functional trait approach was applied to investigate patterns of functional diversity and life‐history traits of ground beetles and spiders on an alpine debris‐covered glacier and along its forefield in order to describe their colonisation strategies. 3. Ground beetles and spiders were sampled at different successional stages, representing five stages of deglaciation. 4. The results show that the studied glacier hosts ground beetle and spider assemblages that are mainly characterised by the following traits: walking colonisers, ground hunters and small‐sized species. These traits are typical of species living in cold, wet, and gravelly habitats. The diversity of functional traits in spiders increased along the succession, and in both carabids and spiders, life‐history traits follow the ‘addition and persistence model’. Accordingly, there is no turnover but there is an addition of new traits and a variation in their proportion within each species assemblage along the succession. The distribution of ground beetles and spiders along the glacier foreland and on the glacier seems to be driven by dispersal ability and foraging strategy. 5. The proposed functional approach improves knowledge of the adaptive strategies of ground‐dwelling arthropods colonising glacier surfaces and recently deglaciated terrains, which represent landforms quickly changing due to global warming.     

Defensive secretions of larvae of a carabid beetle

Secretions of an eversible gland on the metathorax of larvae of Chlaenius cordicollis Kirby (Coleoptera: Carabidae) are investigated by headspace analysis using solid phase microextraction followed by gas chromatography‐mass spectrometry (GC‐MS). Larvae from Manitoba, Canada and Pennsylvania, U.S.A., are sampled. Nine presumed defensive compounds are detected when the gland is everted, and this represents the first characterization of defensive secretions of larvae of a carabid beetle. With the exception of a single component (2‐methoxy‐4‐methylphenol), these compounds are distinct from those found in the defensive secretion of adult C. cordicollis. However, seven are more oxidized versions of the alkylphenolic compounds secreted by adult beetles: three hydroquinones (hydroquinone, methylhydroquinone and 2,3‐dimethylhydroquinone) and four quinones (p‐benzoquinone, toluquinone, 2,3‐dimethylquinone and ethyl‐p‐benzoquinone). An additional alkoxyphenol (2‐methoxy‐4‐ethylphenol) is also detected. Two patterns of composition are observed: in one, p‐benzoquinone and hydroquinone are undetectable and the ratio of toluquinone : 2,3‐dimethylquinone is 1 : 4.6 ± 0.6 (mean ± SE); in the other, all nine compounds are detectable and the ratio of toluquinone : 2,3‐dimethylquinone is 1 : 1.0 ± 0.2. These differences in pattern do not appear to be related to geographical source, sex or age of the larvae.     

Landscape heterogeneity as an ecological filter of species traits

Landscape heterogeneity is a major driver of biodiversity in agricultural areas and represents an important parameter in conservation strategies. However, most landscape ecology studies measure gamma diversity of a single habitat type, despite the assessment of multiple habitats at a landscape scale being more appropriate. This study aimed to determine the effects of landscape composition and spatial configuration on life-history trait distribution in carabid beetle and herbaceous plant communities. Here, we assessed the gamma diversity of carabid beetles and plants by sampling three dominant habitats (woody habitats, grasslands and crops) across 20 landscapes in western France. RLQ and Fourth Corner three-table analyses were used to assess the association of dispersal, phenology, reproduction and trophic level traits with landscape characteristics. Landscape composition and configuration were both significant in explaining functional composition. Carabid beetles and plants showed similar response regarding phenology, i.e. open landscapes were associated with earlier breeding species. Carabid beetle dispersal traits exhibited the strongest relationship with landscape structure; for instance, large and apterous species preferentially inhabited woody landscapes, whereas small and macropterous species preferentially inhabited open landscapes. Heavy seeded plant species dominated in intensified agricultural landscapes (high % crops), possibly due to the removal of weeds (which are usually lightweight seeded species). The results of this study emphasise the roles of landscape composition and configuration as ecological filters and the importance of preserving a range of landscape types to maintain functional biodiversity at regional scales.     

A new species of the genus Laboulbenia (Laboulbeniales) on Ophionea indica (Coleoptera, Carabidae, Odacanthini) from Taiwan

Laboulbenia ophioneae is described as a new species with illustrations. It is closely related to Laboulbenia celestialis and Laboulbenia asiatica because of some similarities in the morphology of appendages and perithecia. The present species from the latter two species can be distinguished by the shorter, inflated perithecia, the shorter receptacles, and the appendages consisting of more or less darkly colored, broader branches. This new species was found on elytra of Ophionea indica from Taiwan, which has been also known as a host of Laboulbenia polymorpha. A mature thallus noticed by Terada (2004) on the slide 673b (M. Ishikawa collection) and a young thallus illustrated by Sugiyama (1978, fig. 1-G as L. polymorpha) on 673d (M. Ishikawa collection) are both identified as L. ophioneae.     

Diet of the marsh deer (Blastocerus dichotomus) in the Pantanal wetland,Brazil

O cervo-do-pantanal (Blastocerus dichotomus, Cervidae) é uma espécie sul americana ameaçada de extinção. Existe pouca informação sobre a biologia desta espécie, incluindo dieta e requerimentos de habitat. O objetivo deste estudo foi determinar as espécies de plantas forrageadas pelo cervo no Pantanal, Brazil, onde se localiza a maior parte de sua população. A dieta do cervo-do-pantanal foi estudada através de microhistologia de restos vegetais em amostras de fezes. Um total de 41 espécies foram identificadas como componentes da dieta, 32 delas sendo consumidas durante a estação de cheias e 31 na estação seca. A maioria das espécies de plantas detectadas na dieta do cervo-do-pantanal é composta de plantas aqu ticas e/ou que apresentam tolerância a inundaç[otilde]es sazonais ou solos encharcados. Blastocerus pode ser melhor definido como um estrategista "pastador-podador" porque grande parte de sua dieta é composta de brotos de várias espécies arbustivas e macrófitas de folha larga. The marsh deer (Blastocerus dichotomus, Cervidae) is a South American endangered species. There is little information on the biology of this species, including diet and habitat requirements. The objective of this study was to determine the plant species foraged by the marsh deer in the Pantanal wetland, Brazil, where most of its population is found. Marsh deer's diet was studied through microscopic analysis of fecal samples for remnants of plant species. A total of 41 species were identified as components of the diet, 32 of them found to be consumed during the flooding season and 31 in the dry season. Most plant species detected in the marsh deer's diet are aquatic and/or present tolerance to seasonal flooding and water-logged soils. Blastocerus could be best defined as a grazer-browser strategist because large part of its diet is composed of shoots of several species of shrub and broad-leaved aquatic macrophytes.     

A?new species of the genus Duvalius sg. Neoduvalius from Montenegro with taxonomical remarks on the genus Duvalius (Coleoptera,Carabidae, Trechini)

Duvalius (sg. Neoduvalius) gejzadunayi sp. n. from Pećina u Dubokom potoku cave ( Donje Biševo village near Rožaje, Montenegro), the first known representative of this subgenus from the territory of Montenegro is described, illustrated and compared with the related species of the subgenus Neoduvalius Müller, 1913. This new species is characterised by depigmented, medium sized body, totally reduced eyes, deep and complete frontal furrows, 3–4 pairs of discal setae in third elytral stria, as well as by the shape of aedeagus. Data on the distribution and the ecology of this remarkable species, as well as a check-list of the subgenus Neoduvalius are also provided. Recently described genera Serboduvalius Ćurčić, S. B. Pavićević & Ćurčić, B.P.M., 2001, Rascioduvalius Ćurčić, S. B. Brajković, Mitić & Ćurčić, B.P.M., 2003, Javorella Ćurčić, S. B. Brajković, Ćurčić, B.P.M. & Mitić, 2003 and Curcicia Ćurčić, S. B. & Brajković, 2003 are regarded as junior synonyms of the genus Duvalius Delarouzée.