No abstract

Developing protocols for threatened invertebrates is often challenging, because they are not only rare but also elusive. This is the case with the stag beetle (Lucanus cervus), a protected and flagship species for the saproxylic beetle fauna in Europe. We applied a standard transect walk at a European scale (8 countries, 29 transects) to test its practicability and reliability as survey design. A total of 533 sightings were recorded throughout the sampling period, but detection probability changed as the season progressed. Considering the observed activity pattern, occupancy models showed that a short period of three consecutive weeks, between the middle of June and the first week of July, resulted in a high probability of detection (P > 0.7). As time of the peak of activity varies from year to year and between sites, we propose to extend the sampling period to five weekly surveys. Detailed information on the transect characteristics and the optimal time for surveying were analysed. The data indicate that a weekly transect at dusk provides a reliable method for monitoring this species throughout its distributional range. No correlation was found between latitude, longitude and phenology of sightings, however. However, a standard method such as the one presented, allows broadening the scale of monitoring studies, provinding data to evaluate the efficacy of conservation measures. © 2016 The Royal Entomological Societ

Two Cordulegaster dragonflies present in Italy, the Palaearctic and northern distributed Cordulegaster boltonii and the endemic to the south of the peninsula Cordulegaster trinacriae, meet in central Italy and give rise to individuals of intermediate morphology. By means of mitochondrial and nuclear markers and of Geometric Morphometrics applied to sexual appendages, we defined i) the geographical boundaries between the two species in Italy and ii) we determined the presence, the extent, and the genetic characteristics of the hybridization. Genetic data evidenced asymmetric hybridization with the males of C. trinacriae able to mate both interspecifically and intraspecifically. The results contrast with expectations under neutral gene introgression and sexual selection. This data, along with the morphological evidence of significant differences in size and shape of sexual appendages between the males of the two species, seem indicative of the role of mechanical constraints in intraspecific matings. The origin of the two species is dated about to 1.32 Mya and the hybridization resulted related to range expansion of the two species after Last Glacial Maximum and this led to the secondary contact between the two taxa in central Italy. At last, our results indicate that the range of C. trinacriae, a threatened and protected species, has been moving northward probably driven by climate changes. As a result, the latter species is currently intruding into the range of C. boltonii. The hybrid area is quite extended and the hybrids seem well adapted to the environment. From a conservation point of view, even if C. trinacriae has a strong genetic identity, the discovery of hybridization between the two species should be considered in a future species management.

Summary 1. Fluctuating asymmetry has been used widely to investigate questions concerned with evolution and behaviour, and to study the effects of environmental pollution. Damselflies have been used to answer questions in both fields, but no attempt has been made to combine the knowledge from these areas to investigate whether and how evolutionary ecology and behaviour interfere with the use of fluctuating asymmetry as a bioindicator of water pollution. 2. Four hypotheses were formulated to investigate possible interferences: (1) Paired males should be less asymmetrical than unpaired males. (2) Males caught at breeding sites should be less asymmetrical than females caught at breeding sites. (3) Damselflies caught earlier in the season should be less asymmetrical than those caught later in the year. (4) Damselflies caught at control sites should be less asymmetrical than those caught at sites within areas of high pesticide usage. 3. No significant difference in asymmetry levels was found between paired and unpaired males. 4. Males were significantly less asymmetrical than females. 5. Damselflies caught earlier in the year were less asymmetrical than those caught later. 6. The data used to test the hypothesis that fluctuating asymmetry in the wings of mature damselflies reflects the level of pesticides used in the surrounding environment were equivocal. 7. The findings suggest that evolutionary ecology and behaviour interfere with the suitability of fluctuating asymmetry in mature damselflies as a biomonitoring tool and it is concluded that fluctuating asymmetry in emerging adults should be much more appropriate as a bioindicator.

Summary1. Previous laboratory experiments have shown that the insecticide carbaryl reduces emergence success and increases¯uctuating asymmetry in cell patterns of damsel¯y wings. These eects were validated using mesocosms. Twenty arti®cial ponds, each containing Xanthocnemis zealandica, were exposed to three replicated (n = 5) concentrations of carbaryl contamination plus controls. Emergence success, level of¯uctuating asymmetry in meristic and metric traits of the wings, and average size of the damsel¯ies were measured. 2. The degradation of carbaryl was relatively constant for the ®rst 5 weeks but later increased considerably, probably because of enhanced biodegradation. 3. Carbaryl at 100 p.p.b. (nominal concentration) reduced emergence success 10 days after application, whereas carbaryl at 10 p.p.b. and 1 p.p.b. had no eect. 4. To investigate how the level of¯uctuating asymmetry and size were aected by carbaryl, damsel¯ies from ponds with the highest concentration where emergence success was not aected (10 p.p.b.) were analysed over four time periods. Fluctuating asymmetry of the wings increased during the season but was not aected by carbaryl at 10 p.p.b. 5. Size, measured as average length of the front wings, was aected by date of emergence but not by exposure to carbaryl at 10 p.p.b. 6. Three main reasons for the absence of increased levels of¯uctuating asymmetry as a result of carbaryl exposure are suggested.