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Lenzi A., Maurizi E., Mosconi F., Cecchetti M., Francescato S., Noal A., Stolfa G., Roversi P. F., Campanaro A. – Osmoderma eremita (Scopoli, 1763) (Coleoptera Scarabaeidae Cetoniinae) in Circeo State Forest (Central Italy). Osmoderma eremita (Scopoli, 1763) was recorded for the first time in Circeo State Forest (SAC IT6040014) by volunteers participating at the LIFE ESC360 Project “360 volunteers for monitoring forest biodiversity in the Italian Natura 2000 Network”. This finding is the result of several surveys started in 2018 that have been carried out using different sampling methodologies, including a conservation detection dog. Two male specimens of O.eremita have been collected in summer 2021, by the use of black cross windows traps baited with the species pheromone. This record provides new information on the scattered distribution of this species in the Latium Region and confirms the biodiversity value of Circeo State Forest. Furthermore, this result corroborates the importance of cooperation between non-experts and scientists, i.e. citizen science. This approach is essential to carry out monitoring programmes aimed at assessing the conservation status of protected species. Meanwhile, it allows to involve, educate, and raise awareness among non-experts, resulting in the establishment of a general positive mindset and attitude towards forest biodiversity. Key Words: Saproxylic beetles, Citizen Science, Foresta Demaniale del Circeo, Natura 2000, Osmoderma eremita, LIFE project

The study of behavioural ecology of rare and elusive species can be challenging, but it is an important issue for monitoring populations in planning conservation actions. This is especially true for arboreal insects inhabiting old-growth forests, whose habits are scarcely known and rely on many anecdotal data, such as the stag beetle Lucanus cervus (Linnaeus, 1758). In order to gather information on daily activity and behaviour of this species, a radio-telemetry study was conducted in a relict broadleaf forest surrounded by intensively cultivated land in northern Italy. During 2014 and 2015, from May to July, 55 stag beetles (34 males, 21 females) were radio-tagged. Most of them were caught with the aid of an entomological hand net, but nine of them were captured by emergence traps set up on deadwood. Visual contact analysis confirmed that stag beetle males were less elusive than females. Males were more frequently radio-tracked in flight, females mostly underground and in proximity of deadwood. Males were mostly observed flying at sunset, and resting or walking on standing trees during the day. The combination of air temperature and humidity determined the optimal weather conditions for male flights (temperature range: 20.7–26 °C, humidity range: 65.5–78.3%). Flying at sunset, mostly performed by males, significantly increased the detectability of the species and supported the selection of the ‘transect walk at dusk’ as the best monitoring method for the stag beetle.

Lucanus cervus is one of the most charismatic saproxylic beetles, widely distributed in Europe. The species is typical of mature deciduous forests, especially oak woodlands. Loss and fragmentation of suitable habitats is one of the major threats for this species which is included in Annex II of the Habitats Directive. Despite several studies carried out in the last years for the monitoring methods of the species, an analytical comparison between them is still lacking. The aims of this paper are (i) to review the current knowledge about systematics, ecology and conservation practices on L. cervus and (ii) to present the research carried out during the Life MIPP project, in order to define a standard monitoring method with a suitable protocol to be used for addressing the obligations of the Habitats Directive. Overall, five methods were tested during three years in two different study areas. Based on these results, a suitable standard method for L. cervus is proposed in this paper and, in order to assess the conservation status of populations and to compare them over time, a simple method for the calculation of a reference value is provided.

Morimus asper is a morphologically variable longhorn beetle that occurs in large parts of southern and central Europe. Although this saproxylic beetle is widespread in old-growth forests or well-structured woodlands, its populations are currently threatened by forest practices, such as the removal of wood (branches and logs). Morimus funereus is considered a valid species by some authors and is included in Annex II of the Habitats Directive. However, a recent molecular study found that all European and Turkish populations should be referred to a single species, M. asper. In this paper, the monitoring methods proposed for M. asper (sensu lato) in the various European countries are reviewed and the research carried out in Italy, which was aimed at developing guidelines for its monitoring, is presented. The experiments conducted, mainly with log piles built from freshly cut wood, investigated, amongst other things, the importance of wood type, diameter of logs and age of wood for the number of individuals observed. Based on these results and on a literature review, a detailed monitoring method for M. asper is proposed here, together with a discussion on its constraints, spatial validity and possible interferences. In order to facilitate the assessment of the conservation status of populations of M. asper and to allow for comparisons between populations and over time, a method for the calculation of a reference value, based on the monitoring method, is also presented.

The social parasitic beetle Paussus favieri (Coleoptera, Carabidae, Paussini) performs different types of stridulations, which selectively mimic those emitted by different ant castes of its host Pheidole pallidula (Hymenoptera, Formicidae, Myrmicinae). However, the significance of this acoustical mimicry for the success of the parasitic strategy and the behaviors elicited in the host ants by stridulations was unknown. We reared Paussus favieri in Pheidole pallidula colonies and filmed their interacting behaviors. We analyzed in slow motion the behavior of ants near a stridulating beetle. We analyzed separately trains of pulse (Pa + Pb, produced by repeated rubbings) and single pulse (Pc, produced by a single rubbing) of stridulations, clearly recognizable from the shaking up and down of the beetle hind legs, and associated them with different ant responses. The full repertoire of sounds produced by P. favieri elicited benevolent responses both in workers and soldiers. We found that different signals elicit different (sometimes multiple) behaviors in ants, with different frequency in the two ant castes. However, Pc (alone or in conjunction with other types of pulses) appears to be the type of acoustic signal mostly responsible for all recorded behaviors. These results indicate that the acoustic channel plays a pivotal role in the host-parasite interaction. Finding that a parasite uses the acoustical channel so intensively, and in such a complicated way to trigger ant behaviors, indicates that acoustic signals may be more important in ant societies than commonly recognized.

The aim of this study was to characterize the antennal morphology of Osmoderma eremita, a threatened scarab beetle inhabiting tree hollows. O. eremita males produce a sex pheromone, (R)-(+)-γ-decalactone, responsible mainly for the attraction of females but also other males. Gross and fine morphology of microstructures including sensilla, microsculpture and pores were analyzed using Scanning Electron Microscopy. The antenna of O. eremita showed the typical lamellicorn shape of scarab beetles, with a basal scape, a pedicel, a funicle composed of five antennomeres and a club composed of three lamellae. Six different subtypes of sensilla chaetica (Ch.1 - 6), Bohm sensilla (Bo), one subtype of sensilla basiconica (Ba.1), two subtypes of sensilla coeloconica (Co.1 - 2), two subtypes of sensilla placodea (Pl.1 - 2), pores and peculiar folds were described. The two sexes did not show any significant differences in the occurrence and number of the sensilla placodea, known to be responsible for the pheromone reception. Instead, some sexual differences were found on the occurrence and topology of three different microstructures: (1) one subtype of sensillum chaeticum (Ch.2) occurring on the pedicel only in males; (2) a characteristic pore occurring on the funicle only in males; (3) a peculiar fold occurring on different antennomeres of the funicle in the two sexes, on the fourth in males and on the fifth in females. A comparison between sensilla of O. eremita and those of other Scarabaeoidea is provided.

Monitoring of rare or localized saproxylic species is essential for assessing species extinction risk and to investigate the ecological integrity of forests. Morimus asper (Sulzer, 1776) (Coleoptera, Cerambycidae) is a longhorn beetle for which many aspects of its biology are still unknown and this hampers the development of a standard monitoring protocol. Here we investigated two different systems to attract M. asper in the Reserve Bosco della Fontana (Italy): freshly cut log piles (FCLPs) and pitfall traps baited with selected chemical compounds. The FCLPs were composed from logs of two tree species (Quercus robur L. or Carpinus betulus L.) utilizing wood of three diameter classes (small: 5–12 cm; medium: 13–30 cm; large: 31–60 cm). The occurrence and the detection of M. asper varied during the season and during the time of the day. M. asper was more common in the first half of the season and was more frequently detected at 20:00. Occupancy models did not show a clear influence of log diameter and tree species on species occupancy. In contrast, when analysing the abundance data, a significantly higher number of individuals was intercepted on FCLPs made from Q. robur and on those with a diameter above 13 cm. The baited pitfall traps did not catch any M. asper, even though some of the substances tested are known to attract other species belonging to the same subfamily (Lamiinae).

1. The stag beetle, Lucanus cervus (Linnaeus, 1758) (Coleoptera: Lucanidae), is a flagship species for the conservation of European old-growth forests. Despite its popularity and many studies conducted, the lack of knowledge of its habits and ecological requirements leads to difficulties in locating the species in the field and to provide information for suitable planning conservation actions suitable for the species. 2. In order to gather information on dispersal ability and space use, a radiotelemetry study was conducted in a relict floodplain forest surrounded by intensively cultivated land. During 2014 and 2015, from May to July, 55 beetles (34 males, 21 females) were radio-tagged, and 9 of these (7 males, 2 females) were telemetered immediately after the emergence from their development sites, by means of emergence traps. 3. The use of radio-telemetry allowed to detect the oviposition sites and to study the first part of the adult life, when they resulted to be more active. Males were more prone to disperse than females but the home range size did not differ between the sexes. Dividing the season in three intervals, the most active individuals were recorded during the first and the second ones (first and second half of June).

The implementation of conservation actions requires a reliable assessment of presence and/or abundance of targeted species. This is particularly difficult for rare and elusive species. In this study the use of bottle traps and the effects of two potential baits in relation to height in the trees were tested to detect presence and assess abundance of stag beetles (Lucanidae) and flower chafers (Scarabaeidae, Cetoniinae), an important component of forest biodiversity. The study was carried out in a flood-plain forest of northern Italy. Forty-eight handcrafted traps were assigned to two height categories (1.5–2 m and 10–20 m) and three kinds of bait: (i) red wine, white wine and sugar, (ii) red wine, beer and mashed banana, (iii) no bait, as control. Fieldwork lasted 8 weeks, with 32 surveys, from May to July. Overall, we recorded 399 captures of the following species: Dorcus parallelipipedus, Lucanus cervus, Cetonia aurata, Protaetia speciosissima, P.affinis, P. morio and P. cuprea. Traps baited with red wine, white wine and sugar showed the highest detection probabilities for all the species. A clear preference for the canopy layer (traps between 10 and 20 m high) was shown by all species except for D. parallelipipedus which was mostly captured between 1.5 and 2 m of height. The study period was long enough to improve ecological knowledge on species phenology, but not enough to include the whole phenology for all of them. The method allowed the assessment of population size only for flower chafers as the number of stag beetles captures was too low.

Citizen science, the engagement of people in a research project, has grown rapidly in recent years, also for mapping of species of conservation interest. The Life Project "Monitoring Insects with Public Participation" (MIPP) actively promoted collaboration amongst scientists, public administrations and citizens in the collection of occurrence data of nine insect species listed in the Habitats Directive: Lucanus cervus, Osmoderma eremita, Cerambyx cerdo, Rosalia alpina, Morimus asper/funereus, Lopinga achine, Parnassius apollo, Zerynthia cassandra/polyxena and Saga pedo. These species were selected because they share two main characteristics: (i) they are listed in Annexes II and IV of the Habitats Directive and (ii) they are large and relatively easy to identify. From 2014 to 2016, many different strategies were applied to contact and engage the public and approximately 14,000 citizens were reached directly. Additionally, printed and online material informed the public about this project. Citizens could transmit data on the target species, accompanied by a photograph, via the web-site of the project or through a dedicated application (app) for smartphones and tablets. All records were validated by experts based on the photographs sent by citizens. A total number of 2,308 records were transmitted and 1,691 (73.2%) of these were confirmed. Most of the reports were submitted via the website, although the submission via the app increased over time. The species most commonly recorded was L. cervus, followed by M. asper/funereus and R. alpina. Data collected by citizen scientists allowed a detailed analysis to be made on altitudinal distribution and phenology of the species and the results obtained were compared with literature data on altitudinal distribution and phenology. For example, for L. cervus, 67% of the records collected were from the altitudinal range 0–400 m a.s.l. Interestingly, the data showed that the phenology of this species changed with altitude.

""\\"Few studies have investigated insect ensembles, i.e. phylogenetically bounded groups of. species that use a similar set of resources within a community. The zonation of dune. vegetation makes these ecosystems ideal for the study of insect ensembles in a short space.. In this study, we investigated if the tenebrionid beetles forming an ensemble on a dune. zonation showed variations in community organization (relative abundances and species. diversity) in different but spatially associated biotopes defined by different plant. communities. Three biotopes (corresponding to European Commission habitat 2110, 2120. and 2230) of a well-preserved Mediterranean dune were sampled using square plots of. 2 2 m at three places. To investigate if there was some association between species and. habitat we applied a x2 test. Variations in community structure parameters were. investigated using Shannon index. The three biotopes host tenebrionid communities with. similar species composition and overall abundances, confirming that they form a single. ensemble. However, tenebrionid species are differently associated with different biotopes. along the zonation, with some species occurring with different proportions among the. biotopes. A local selection process can be postulated as a mechanism responsible for these differences.\\"""

We evaluated the completeness and historical trends of the taxonomic knowledge of the myrmecophilous ground beetle tribe Paussini (Coleoptera, Carabidae, Paussinae). Species accumulation curves were modelled using a logistic function. Similar analyses were conducted for genera and subgenera. Although not all biogeographical regions have been equally explored, accumulation curves reached a plateau in all cases. Our models predict that about 96% of the world fauna has been already described. However, the asymptotes calculated for the Australian and Oriental species should be interpreted as false plateaus because of the lack of recent research. Similarly, patterns of genera accumulation indicate that a plateau has been reached. As a result of continued debate on the use and validity of Paussini subgenera, the accumulation curves of subgenera showed stepped patterns, with no evidence of plateaus. Thus, although relatively few species are expected to be described in the future, the species accumulation curves indicate that the taxonomic inventory is not yet complete. Differences in accumulation patterns among biogeographical regions can be used to highlight the areas where more species are expected, and hence where taxonomical efforts should be concentrated. © 2012 The Linnean Society of London, Biological Journal of the Linnean Society, 2012, 105, 330–339.

Global change imposes rapid assessments to obtain reliable and updated distribution data to implement conservation measures. This task is undoubtedly unaffordable for numerous invertebrate species, both in terms of time and economic resources, because they are often elusive, detectable life stages are present for a restricted time and ecological data are scarce. Citizen science might be able to provide a large number of records and these data might facilitate the evaluation of extinction risks. Large saproxylic beetles represent an ideal group to assess the potential of citizen science to map distributions on a large scale geographic distribution. The data presented were collected during a citizen science program developed within the LIFE Project “Monitoring of Insects with Public Participation”, which used a website and a mobile app to involve citizens. We selected three pan European species protected under the Habitats Directive: Lucanus cervus , Morimus asper / funereus and Rosalia alpina , and we compared the data gathered by the citizen science project with distributional data from the official national species inventory. For all species we found a low overlap of occupied cells and the integration of the two datasets resulted in an increase in the distributional ranges of up to one third. Furthermore, taking into account the time frame of data collection, we found that the extent of occurrence obtained in 10 years of records present in the national dataset was comparable to data collected in only two years of the citizen science data project. Similar results were obtained for the estimates of spatial parameters for the IUCN Red List assessment. Our study shows the potential and the efficacy of citizen science projects as rapid tools to provide reliable distributional data for neglected species of high conservation priority.

The aim of this study was to characterize the antennal morphology of Osmoderma eremita, a threatened scarab beetle inhabiting tree hollows. O. eremita males produce a sex pheromone, (R)-(+)-γ-decalactone, responsible mainly for the attraction of females but also other males. Gross and fine morphology of microstructures including sensilla, microsculpture and pores were analyzed using Scanning Electron Microscopy. The antenna of O. eremita showed the typical lamellicorn shape of scarab beetles, with a basal scape, a pedicel, a funicle composed of five antennomeres and a club composed of three lamellae. Six different subtypes of sensilla chaetica (Ch.1 - 6), Böhm sensilla (Bo), one subtype of sensilla basiconica (Ba.1), two subtypes of sensilla coeloconica (Co.1 - 2), two subtypes of sensilla placodea (Pl.1 - 2), pores and peculiar folds were described. The two sexes did not show any significant differences in the occurrence and number of the sensilla placodea, known to be responsible for the pheromone reception. Instead, some sexual differences were found on the occurrence and topology of three different microstructures: (1) one subtype of sensillum chaeticum (Ch.2) occurring on the pedicel only in males; (2) a characteristic pore occurring on the funicle only in males; (3) a peculiar fold occurring on different antennomeres of the funicle in the two sexes, on the fourth in males and on the fifth in females. A comparison between sensilla of O. eremita and those of other Scarabaeoidea is provided.

The LIFE project “MIPP” - Monitoring of Insects with Public Participation (11 NAT/IT/000252) is focused on selected insect species (five Coleoptera, three Lepidoptera, one Orthoptera), all included in the annexes II and IV of the Habitats Directive (HD) 92/43/EEC. One important aim is a citizen science initiative where every person may become a citizen scientist and collect faunistic data on the above species throughout Italy. Another objective of the project MIPP is the development of standard methods for monitoring the conserva- tion status of the five target beetle species. One innovative method employed is a sniffer-dog (“Osmodog”), trained to find the rare and endangered hermit beetle, Osmoderma eremita, which lives in veteran, hollow trees. The dog detects the strong smell of mature peach produced by adult males and an odor produced by the larvae. Another objective of the project MIPP is the dissemination of topics such as HD, Natura 2000, importance of dead-wood, Life projects, insect monitoring and conservation., Fragmenta Entomologica, Vol. 47 No. 1 (2015)

Paussus favieri Fairmaire is one of only two species of the myrmecophilous carabid tribe Paussini known from Europe. Larvae are known from only 10 of the 580 paussine species. As in many beetles with considerably modified later instar larvae, the first instars represent a valuable source of informative characters for taxonomy and phylogenetic analyses (primary chaetotaxy, eggbursters, etc.). Therefore, the discovery of the first instar larva of P. favieri is particularly important, as it represents only the second species for which this larval stage is known. In this paper we describe the behavior and morphology of the larval first instar of P. favieri (subtribe Paussina of Paussini) and compare it with that of Arthropterus sp. (subtribe Cerapterina), which is the only other 1st instar described in the Paussini. Most surprisingly, we found that the 1st instar of P. favieri lacks a prostheca, which was previously thought to be a synapomorphy of Paussina + Platyrhopalina. Rather, P. favieri has a unique mandibular structure that seems to be functionally analogous to the protheca. It is a long, broadly lanceolate, distinctly flattened structure apparently homologous to the medial mandibular seta (MN2*), which arises from an area behind the cutting edge of mandible. We predict that the function of the protheca and this similar structure in P. favieri are involved in a specialized feeding strategy that may include soliciting trophallaxis from their host ants. We also report some observations of the first instar hatching from the egg, feeding on liquid and a behaviour we interpret as a “calling behavior,” all of which were videotaped and posted on the Tree of Life Web Project.

The evolution of a myrmecophilous lifestyle in beetles is often associated with morphological alterations. In particular, the antennae of all members of the myrmecophilous ground beetle tribe Paussini are greatly modified, with flagellomeres flattened or crassate, frequently reduced in number from 9 to 5 or even 1 single "antennal club". The enhanced glandular function of the antennal club has been recently described by scanning (SEM) and transmission (TEM) electron microscopy in Paussus favieri Fairmaire, 1851, where the antenna has become a complex glandular organ, supplying rewarding substances to the ants. In the present work, the antennal sensilla of P. favieri are investigated by SEM, TEM and focused ion beam (FIB/SEM) technology. Most sensilla of scape and antennal club are highly modified mechanoreceptors (i.e. multipointed, fringed, branched, brush-like, sickle-shaped), singly or grouped in tufts ("antennal symphilous organs"). These "trichomes", here assigned to 8 different morphotypes of sensilla chaetica (Ch.1-Ch.8), show a variable number of basal pores (present also at the base of the taste sensilla Ch.9), which spread dense substances of unknown chemical composition on the seta. Although hygro-, thermo- and chemoreceptors are reduced in number as compared with non-myrmecophilous relatives, and mainly relegated to the apex of the antennal club, their diversity is comparable to that of other carabid beetles: two types of sensilla trichodea (Tr.1-Tr.2); three types of basiconica (Ba.1-Ba.3); one type of campaniformia (Ca); one type of coeloconica (Co) and one type of Böhm sensilla (Bo). Contrary to the hypothesis that Paussus species lack a Johston's organ, a non-connective chordotonal organ composed of 9 groups of scolopidia has been found inside the pedicel. A comparison between sensilla of P. favieri and those of other non-myrmecophilous and myrmecophilous ground beetle species is provided.