1,721,035 research outputs found
Insecta Coleoptera Carabidae (Carabini, Cychrini, Trechini, Abacetini, Stomini, Pterostichini)
No full textMemorie del Museo Civico di Storia Naturale di Verona 2. serie - Sezione Scienze della Vita 1
Morphometry and eye morphology in three species of Carabus (Coleoptera: Carabidae) in relation to habitat demands
No full textMorphological features of three common European olfactory hunting carabid beetles, Carabus coriaceus mediterraneus Born, 1906, Carabus lefebvrei Dejean, 1826 and Carabus preslii neumeyeri Schaum, 1856, were compared. According to eye measurements, the three species are nocturnal and/or twilight hunters. They differ, however, in relative length of the antennae, relative surface area of the compound eyes, density of ommatidia and relative head width. These differences can be correlated with the species-specific habitat demands (light intensity, open land or shaded places). In particular, the greater lateral eye protrusion in C. lefebvrei corresponds to its tree-climbing habits, while the larger relative eye surface area and ommatidia density in C. coriaceus correspond to its choice of open habitats. © 2007 The Authors Journal compilation 2007 Blackwell Verlag
Non aggressive behavioural interaction in larvae of the ground beetle species Chlaenius velutinus (Coleoptera : Carabidae)
No full textLarvae of the Chlaenius velutinus (Duftschmidt 1812) search for prey on the surface of humid river banks, with their flexible cerci held upright on their back. They live in dense populations in temporary habitats, where mutual encounters are usual. Laboratory observations demonstrate active cerci interactions between conspecific larvae. The behaviour on encounter of C velutinus larvae is described and the frequencies and sequence of 3 types of behaviour involving the cerci are analysed. This behaviour is thought to be a mutual interaction behaviour through which the larvae lower their aggressiveness avoiding cannibalism
Note tassonomiche e corologiche su Carabus granulatus in Italia, con descrizione di una nuova sottospecie di Calabria (Coleoptera, Carabidae).
No full textAnalisi della diversità funzionale di coleotteri carabidi (Coleoptera, Carabidae) del Parco Naturale Regionale di lama Balice (Puglia)
No full textPreliminary information about population of Ground Beetles (Coleoptera Carabidae) of Natural Regional
Park of Lama Balice (South Italy, Bari) are reported here. Study of species composition and dominance
structure pointed out presence of few dominant species. Analysis of sampled vegetation macro-units (or
habitats) highlighted that functional diversity of sampled ground beetles community showed valuable
differences in structural and functional features of communities between different habitats. In the “macchiagariga”
(shrub-garrigue) there was an increase of feeding-opportunistic species and we found sole seedeaters.
In the “ vegetazione erbacea di fondo lama” (grass vegetation of deep lama) we found specialised predators
Harpalus (Pseudoophonus) rufipes as a model to study cellular and humoral immune defence strategies in coleopteran species
Full text linkCarabids are of special interest as environmental quality assessment indicators of exposure to xenobiotic and for pest control. In agroecosystems, they can be exposed to a wide range of pathogens and environmental pollution exerting a stronger selection on their innate immune systems. Therefore, information on species-specific immunocompetence is necessary to complete the ecological framework of ground beetles. In this study, cellular and humoral responses were characterized in adults of Harpalus (Pseudoophonus) rufipes (De Geer, 1774) to define a baseline knowledge for future ecotoxicological studies. The circulating hemocytes were characterized by light and transmission electron microscopy and in vivo assay performed by injecting latex beads to identify phagocytizing hemocytes. Ultrastructural analyses revealed four morphologically distinct types of circulating hemocytes: prohemocytes, plasmatocytes, granular cells and oenocytoids. Differential hemocyte counts showed that plasmatocytes and granular cells were the most abundant circulating cell types and granular cells exhibited phagocytic activity following immune challenge with latex beads. Mitotic figures and non-differentiated hemocytes observed under light microscopy indicate a continuous cell turnover in the hemolymph. Melanotic nodules found 2h after the immune challenge were formed to immobilize the latex beads. Phenoloxidase (PO) assays revealed an increase of basal PO activity in hemolymph after immune system activation with lipopolysaccharide (LPS). However, the LPS-stimulated adults showed no significant variation in the lysozyme-like enzyme activity in hemolymph. Based on these results, H. rufipes displays a rapid, non-specific immune response involving cellular and humoral effectors that both sequester and clear pathogens
What is going on between aposematic carabide beetles? The case of Anchomenus dorsalis (Pontoppidan, 1763) and Brachinus sclopeta (Fabricius, 1792) (Coleoptera, Carabidae)
Full text linkInterspecific aggregations among insects are quite common, but not among carabid beetles. Moreover, aggregations of aposematic species, and morphologically similar beetles such as Anchomenus dorsalis and Brachinus sclopeta are even rarer. Most interestingly, in these aggregations, we observed a peculiar rubbing behaviour of A. dorsalis towards B. sclopeta. In this study we aimed (i) to verify if A. dorsalis displays the rubbing behaviour towards non-aposematic species, (ii) to describe in detail and to quantify this behaviour between A. dorsalis and B. sclopeta, and (iii) to verify if previous experience of inter-specific gregariousness with the same species may exert some effects on the frequency of the rubbing display.
We have investigated the qualitative and quantitative characteristics of rubbing behaviour towards aposematic and non-aposematic carabide beetle species, and then we used A. dorsalis and B. sclopeta as model species. We tested the rubbing of A. dorsalis towards B. sclopeta with either solitary A. dorsalis or in A. dorsalis coming from monospecific (A. dorsalis) or from heterospecific (A. dorsalis and B. sclopeta) aggregations. We finally tested the effectiveness of the B. sclopeta cuticular odour in eliciting rubbing from A. dorsalis by presenting olfactory dummies (special paper) either soaked with water or after it had previously been placed in a monospecific group of B. sclopeta for 15 days.
First of all, we found important differences in the occurrence of rubbing behaviour towards aposematic and non-aposematic species, as A. dorsalis displayed the rubbing only towards the former. Secondly, rubbing frequency depended on the pre-test conditions (isolated, mono- or heterospecific aggregations) of the tested A. dorsalis individuals, as no rubbing occurred in individuals coming from heterospecific aggregations. The paper presentation tests demonstrated that the odour of B. sclopeta was sufficient to provoke rubbing in A. dorsalis.
We conclude that aggregation in these species of carabid beetles may influence their anti-predatory defences possibly increasing the effectiveness of the aposematic (warning) signals.
More work is needed to delineate in detail the evolutionary significance of this behaviour, focusing on the possibility that interspecific aggregations may not be so rare in ground beetles, and that this positive interaction could involve a larger number of species and genera, at least in wet, sun-exposed and open land habitat types
Effects of alternative and specialised diet on development and survival of larvae and pupae in Carabus (Chaetocarabus) lefebvrei (Coleoptera: Carabidae)
No full textCarabus Linnaeus, 1758 species are polyphagous and prey on every kind of food (earthworms, snails, caterpillars and fruit). Some macromorphological differentiations within the genus are often interpretated as related to specialised modes of nutrition. This study examined, in laboratory rearing conditions, larval development and survival under different diets (meat, earthworm, snail and fruit) for Carabus lefebvrei Dejean, 1826. The survival of animals varied significantly with diet. Our results on the survival and duration of development during laboratory rearing revealed that the pre-imaginal development of C. lefebvrei was influenced differently by various diets. The pure-snail diet was essential for fast larval development and adult survival, while the meat and mixed diets were unsuitable for proper development and survival
Peace in ground-beetle larvae: non-aggressive outcome in Chlaenius spp. larvae interactions
No full textCannibalism reduces the number of competitors and provides high-quality food, but it may have costs related to the risk of injury, disease/parasite transmission and reduction of inclusive fitness. Carabid larvae are usually very aggressive, with very low, tolerance of conspecifics. Thus cannibalism is common. We investigated aggressive and cannibalistic behaviour in the larvae-of eight ground beetle species, especially Chlaenius velutinus and Chlaenius spoliatus whose larvae have long articulated cerci. Chlaenius species live in dense populations with frequent intra-specific encounters, whereas encounters are rare in the other species. Dyads of conspecific larvae of the eight ground beetles species were tested for aggressive and cannibalistic behaviour. Unlike the other six species, larvae of the two Chlaenius species avoid cannibalism, possibly as a consequence of a behavioural display involving cerci interactions. This display was never recorded in conspecific larval interactions of the other species. Instead, cannibalism consistently occurred (20 to 50%) following aggressive interactions (1.2 to 2.6 attacks/event). The non-aggressive outcome in Chlaenius larval interactions contrasts with the high aggressiveness (35 to 85% of trials) shown by the other species. This suggests the presence of an inhibitory mechanism in the Chlaenius species. The cerci interaction probably inhibits cannibalism via intra-specific recognition; this behaviour may have evolved under the pressure of ecological factors (resource abundance and dispersion, larvae-density, frequency of encounters). In Chlaenius spp. ecological constraints may have led to an inconvenient costs/benefits trade-off, while in other species-they did not exert negative pressure on the occurrence of cannibalism
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