2,106 research outputs found

    Strange loves: a remarkable case of aberrant copulation in beetles (Coleoptera: Meloidae, Chrysomelidae)

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    A case of copulation between two mimic and repellent beetle species (a male of Timarcha fracassii, and a female of Meloe autumnalis), belonging to distinct families (Chrysomelidae, Meloidae), is recorded

    Description of the first instar larva of Euzonitis rubida with remarks on the systematics of the subfamily Nemognathinae (Coleoptera: Meloidae)

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    The first instar larva (triungulin) of Euzonitis rubida (Ménétriés, 1832) is described and illustrated. This is the first description of a triungulin of the nemognathine genus Euzonitis Semenow, 1893. This larva is very similar to that of the genus Zonitis Fabricius, 1775, the distinction of these two genera remaining difficult by using both larval and adult features. The examination at the scanning electron microscope of several characters of these and other genera of the subfamily Nemognathinae, confirms themain distinction of tribes, but better outlines the condition of some features previously incorrectly defined. Additional species of some genera were also examined and partially figured

    Larval morphology of the genus Cerocoma (Coleoptera: Meloidae) and phylogenetic implications

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    The Palaearctic blister beetle genus Cerocoma Geoffroy, 1762 includes species with great morphological differences in the adults, emphasised in the four subgenera. First instar larvae of three species, belonging to two different subgenera — C. (Cerocoma) schaefferi (Linnaeus, 1758), C. (Metacerocoma) prevezaensis Dvorak, 1993, C. (Metacerocoma) schreberi Fabricius, 1781 — are described and compared to that of the single other species previously known in literature, C. (Cerocomina) vahli Fabricius, 1787. First instar larvae of Cerocoma have typical features of the subfamily Meloinae, without derived characters. No relevant differences were found by a SEM morphological study, and the species can be distinguished only by morphometric characters. Consequently, subgeneric divisions, based on the adult morphology, are not supported by larval characters

    Decoherence, wave function collapses and non-ordinary statistical mechanics

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    We consider a toy model of pointer interacting with a 1/2-spin system, whose σx\sigma_{x} variable is \emph{measured} by the environment, according to the prescription of decoherence theory. If the environment measuring the variable σx\sigma_{x} yields ordinary statistical mechanics, the pointer sensitive to the 1/2-spin system undergoes the same, exponential, relaxation regardless of whether real collapses or an entanglement with the environment, mimicking the effect of real collapses, occur. In the case of non-ordinary statistical mechanics the occurrence of real collapses make the pointer still relax exponentially in time, while the equivalent picture in terms of reduced density matrix generates an inverse power law relaxation

    Short-term effects of canopy and surface fire on centipede (Chilopoda) communities in a semi natural Mediterranean forest

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    Species composition and structure of centipede (Chilopoda) communities were studied in a sub-urban burnt forest on the Mediterranean coast near Roma, Italy. The study was carried out in two sites affected by canopy fire (complete vegetation destruction), one affected by surface fire (persistence of tree canopy), and three unburnt sites. Monthly, quantitative/qualitative samplings were performed in each site from April 2001 to April 2002 by pitfall trapping and one hour active search. Analyses of species composition, dominance structure, diversity and colonization progress were performed. Centipede communities of the sites affected by canopy fire were simply structured, poor in both species richness and diversity; conversely, species composition, structure and diversity of the community affected by surface fire were scarcely modified

    The cranial apparatus glands of the canthariphilous Pyrochroa coccinea (Coleoptera: Pyrochroidae: Pyrochroinae), and their implications in sexual behaviour

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    Some Pyrochroidae species are known as "canthariphilous" for their attraction to cantharidin (CTD), a toxic terpene with anti-predatory effects, produced in nature by only two beetle families (Meloidae and Oedemeridae). It has been demonstrated that males of Neopyrochroa flabellata ingesting CTD are positively selected by females. Indeed, the compound is re-emitted from a glandular cranial apparatus as secretions that are licked up by females during courtship behaviour, inducing copulation. Herein, we provide the first description of the glands associated to the cranial apparatus of male Pyrochroinae using the European species Pyrochroa coccinea as a model. Morphological analyses show that the cranial apparatus consists of a concave pit lined with short setae retaining secretions emitted through numerous glandular pores. Ultrastructural investigations reveal the presence of two different class 3 glands (Gl.A and Gl.B), intermixed at the level of the pit but exhibiting distinct features. Gl.A are mainly characterised by short conducting canals, rounded nuclei and electrondense vesicles while Gl.B are characterised by long conducting canals, irregular nuclei, vesicles containing a particulate substance and a multifolded plasma membrane. Observations of sexual behaviour are also reported for P. coccinea and compared to N. flabellata, confirming the involvement of cranial apparatus secretions in courtship behaviour

    Rural–urban gradient and land use in a millenary metropolis: how urbanization affects avian functional groups and the role of old villas in bird assemblage patterning

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    Abstract. Urbanization generally leads to a complex environmental gradient, ranging from almost undisturbed natural areas to highly modified urban landscapes. Here we analyse the effects of a rural–urban gradient on breeding bird communities and functional species groups in remnant natural and semi-natural areas of Rome. A total of 69 breeding bird species were found in the study area. Species richness decreased with increasing urbanization at two spatial scales: the point count station and the landscape scales. Evenness showed a negative trend from periphery to city centre, whereas for dominant species the opposite was true. Functional species groups responded to the urbanization gradient with functional group-specific patterns. Those groups linked to open habitats (nesting and habitat functional groups) decreased in abundance along the rural–urban gradient, whereas those associated with forests exhibited a mixed trend. Generalist species' occurrence increased with urbanization. As for predators and granivorous species, we found a negative relationship with urbanization whereas for omnivorous species the opposite trend was true. The distribution of old villas (large-sized remnant green areas) in the inner city areas influenced species composition along the studied gradient, usually showing higher species richness than surrounding fragments. Agricultural areas hosted richer and better balanced bird assemblages in respect to those found in urban and forested areas. Our findings proved that an urban gradient plays a major role in structuring bird communities, although the extent and distribution of land use categories was another factor that influenced avian assemblages. The presence of historical villas also influenced bird assemblages, making it possible to preserve high bird diversity even in inner city-areas

    The decline of the Aeolian wall lizard, Podarcis raffonei : causes and conservation proposals

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    Investigations carried out in the Aeolian Islands (off north-east Sicily) during 1989–99 gathered evidence strongly indicating that the endemic Aeolian wall lizard Podarcis raffonei is close to extinction. Competitive exclusion by the lizard Podarcis sicula, which has been introduced by man, habitat degradation, and possibly reduced genetic variability and inbreeding, were the main causes for the decline of the species. For the Aeolian wall lizard to recover from its threatened status and to prevent further decimation of populations, collection and trade in the species should be prohibited, and an education programme for local people should be promoted. An integrated project involving habitat protection and captive breeding is needed to secure the species in the wild for the future
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