@article {58190, title = {Acoustic communication in aquatic animals: all quiet on the freshwater front?}, year = {2013}, doi = {10.1002/aqc.v23.310.1002/aqc.2356}, url = {http://doi.wiley.com/10.1002/aqc.v23.3}, author = {Gammell, Martin P. and O{\textquoteright}Brien, Joanne M.} } @article {58027, title = {Diversity of acoustic tracheal system and its role for directional hearing in crickets}, year = {2013}, abstract = {

Background: Sound localization in small insects can be a challenging task due to physical constraints in deriving sufficiently large interaural intensity differences (IIDs) between both ears. In crickets, sound source localization is achieved by a complex type of pressure difference receiver consisting of four potential sound inputs. Sound acts on the external side of two tympana but additionally reaches the internal tympanal surface via two external sound entrances. Conduction of internal sound is realized by the anatomical arrangement of connecting trachea. A key structure is a trachea coupling both ears which is characterized by an enlarged part in its midline (i.e., the acoustic vesicle) accompanied with a thin membrane (septum). This facilitates directional sensitivity despite an unfavorable relationship between wavelength of sound and body size. Here we studied the morphological differences of the acoustic tracheal system in 40 cricket species (Gryllidae, Mogoplistidae) and species of outgroup taxa (Gryllotalpidae, Rhaphidophoridae, Gryllacrididae) of the suborder Ensifera comprising hearing and non hearing species.

Results: We found a surprisingly high variation of acoustic tracheal systems and almost all investigated species using intraspecific acoustic communication were characterized by an acoustic vesicle associated with a medial septum. The relative size of the acoustic vesicle - a structure most crucial for deriving high IIDs - implies an important role for sound localization. Most remarkable in this respect was the size difference of the acoustic vesicle between species; those with a more unfavorable ratio of body size to sound wavelength tend to exhibit a larger acoustic vesicle. On the other hand, secondary loss of acoustic signaling was nearly exclusively associated with the absence of both acoustic vesicle and septum.

Conclusion: The high diversity of acoustic tracheal morphology observed between species might reflect different steps in the evolution of the pressure difference receiver; with a precursor structure already present in ancestral non-hearing species. In addition, morphological transitions of the acoustic vesicle suggest a possible adaptive role for the generation of binaural directional cues.

}, keywords = {Acoustic tracheal system, cricket, directional hearing, Interaural intensity difference (IID), Pressure difference receiver, Sound localization}, doi = {10.1186/1742-9994-10-61}, url = {http://frontiersinzoology.biomedcentral.com/articles/10.1186/1742-9994-10-61}, author = {Schmidt, Arne KD and R{\"o}mer, Heiner} } @article {58010, title = {A Tympanal Insect Ear Exploits a Critical Oscillator for Active Amplification and Tuning}, journal = {Current Biology}, volume = {23}, year = {2013}, month = {Jan-10-2013}, pages = {1952 - 1957}, abstract = {

A dominant theme of acoustic communication is the partitioning of acoustic space into exclusive, species-specific niches to enable efficient information transfer. In insects, acoustic niche partitioning is achieved through auditory frequency filtering, brought about by the mechanical properties of their ears [1]. The tuning of the antennal ears of mosquitoes [2] and flies [3], however, arises from active amplification, a process similar to that at work in the mammalian cochlea [4]. Yet, the presence of active amplification in the other type of insect ears\—tympanal ears\—has remained uncertain [5]. Here we demonstrate the presence of active amplification and adaptive tuning in the tympanal ear of a phylogenetically basal insect, a tree cricket. We also show that the tree cricket exploits critical oscillator-like mechanics, enabling high auditory sensitivity and tuning to conspecific songs. These findings imply that sophisticated auditory mechanisms may have appeared even earlier in the evolution of hearing and acoustic communication than currently appreciated. Our findings also raise the possibility that frequency discrimination and directional hearing in tympanal systems may rely on physiological nonlinearities, in addition to mechanical properties, effectively lifting some of the physical constraints placed on insects by their small size [6] and prompting an extensive reexamination of invertebrate audition.

}, issn = {09609822}, doi = {10.1016/j.cub.2013.08.028}, url = {https://linkinghub.elsevier.com/retrieve/pii/S0960982213010348https://api.elsevier.com/content/article/PII:S0960982213010348?httpAccept=text/xmlhttps://api.elsevier.com/content/article/PII:S0960982213010348?httpAccept=text/plain}, author = {Mhatre, Natasha and Daniel Robert} } @article {57945, title = {Mechanical tuning of the moth ear: distortion-product otoacoustic emissions and tympanal vibrations}, year = {2013}, abstract = {

The mechanical tuning of the ear in the moth Empyreuma pugione was investigated by distortion-product otoacoustic emissions (DPOAE) and laser Doppler vibrometry (LDV). DPOAE audiograms were assessed using a novel protocol that may be advantageous for non-invasive auditory studies in insects. To evoke DPOAE, two-tone stimuli within frequency and level ranges that generated a large matrix of values (960 frequency\–level combinations) were used to examine the acoustic space in which the moth tympanum shows its best mechanical and acoustical responses. The DPOAE tuning curve derived from the response matrix resembles that obtained previously by electrophysiology, and is V-shaped and tuned to frequencies between 25 and 45 kHz with low Q10dB values of 1.21\±0.26. In addition, while using a comparable stimulation regime, mechanical distortion in the displacement of the moth\’s tympanal membrane at the stigma was recorded with a laser Doppler vibrometer. The corresponding mechanical vibration audiograms were compared with DPOAE audiograms. Both types of audiograms have comparable shape, but most of the mechanical response fields are shifted towards lower frequencies. We showed for the first time in moths that DPOAE have a pronounced analogy in the vibration of the tympanic membrane where they may originate. Our work supports previous studies that point to the stigma (and the internally associated transduction machinery) as an important place of sound amplification in the\ moth ear, but also suggests a complex mechanical role for the rest of the transparent zone.

}, keywords = {Audiogram, DPOAE, Empyreuma pugione, laser Doppler vibrometry, mechanical tuning, moth}, doi = {10.1242/jeb.085902}, url = {http://jeb.biologists.org/cgi/doi/10.1242/jeb.085902https://syndication.highwire.org/content/doi/10.1242/jeb.085902}, author = {Mora, E. C. and Cobo-Cuan, A. and Macias-Escriva, F. and Perez, M. and Nowotny, M. and Kossl, M.} } @article {57941, title = {Review of the Balkan Isophya (Orthoptera: Phaneropteridae) with particular emphasis on the Isophya modesta group and remarks on the systematics of the genus based on morphological and acoustic data}, year = {2013}, abstract = {

A critical review of the taxonomy and systematics of the genus Isophya from the Balkan Peninsula, together with a revision of the I. modesta group, including its representatives outside the Balkans, has been made using morphological, bioacoustic and karyological data. As a result, the following taxonomic considerations have been proposed: (1) the status of two taxa has been reconsidered: Isophya rhodopensis leonorae Kaltenbach, stat.n., I. rhodopensis petkovi Peshev, stat.n.; (2) five synonymies have been established: I. hospodar (Saussure) = I. hospodar medimontana Nedelkov, syn.n.; I. plevnensis Peshev, sensu novo = I. pravdini pravdini Peshev, syn.n.; I. rhodopensis leonorae Kaltenbach = I. kisi Peshev, syn.n.; I. obtusa = I. pravdini bazyluki Peshev, syn.n.; I. modesta Frivaldszky = I. modesta intermedia Kis syn.n. The descriptions of the taxa under consideration are supplemented with unpublished morphological and/or bioacoustic data. An updated list of the taxa occurring on the Balkans includes 24 taxa (21 species, including the doubtful data on I. camptoxypha). A dichotomic and tabulated key for recognition and maps of distribution of the established taxa are presented.

}, keywords = {Anatolia, Barbitistini, Bush-crickets, distribution, evolution, grouping, keys, Southeastern Europe}, doi = {10.11646/zootaxa.3658.110.11646/zootaxa.3658.1.1}, url = {http://biotaxa.org/Zootaxa/issue/view/zootaxa.3658.1}, author = {Dragan Petrov Chobanov and Grzywacz, Beata and Ionut Stefan Iorgu and Battal Ciplak and ILIEVA, MAYA B. and Warcha{\l}owska-{\'S}liwa, El{\.z}bieta} } @article {57643, title = {Low-pass filters and differential tympanal tuning in a paleotropical bushcricket with an unusually low frequency call}, year = {2013}, abstract = {

Low-frequency sounds are advantageous for long-range acoustic signal transmission, but for small animals they constitute a challenge for signal detection and localization. The efficient detection of sound in insects is enhanced by mechanical resonance either in the tracheal or tympanal system before subsequent neuronal amplification. Making small structures resonant at low sound frequencies poses challenges for insects and has not been adequately studied. Similarly, detecting the direction of long-wavelength sound using interaural signal amplitude and/or phase differences is difficult for small animals. Pseudophylline bushcrickets predominantly call at high, often ultrasonic frequencies, but a few paleotropical species use lower frequencies. We investigated the mechanical frequency tuning of the tympana of one such species, Onomarchus uninotatus, a large bushcricket that produces a narrow bandwidth call at an unusually low carrier frequency of 3.2 kHz. Onomarchus uninotatus, like most bushcrickets, has two large tympanal membranes on each fore-tibia. We found that both these membranes vibrate like hinged flaps anchored at the dorsal wall and do not show higher modes of vibration in the frequency range investigated (1.5\–20 kHz). The anterior tympanal membrane acts as a low-pass filter, attenuating sounds at frequencies above 3.5 kHz, in contrast to the high-pass filter characteristic of other bushcricket tympana. Responses to higher frequencies are partitioned to the posterior tympanal membrane, which shows maximal sensitivity at several broad frequency ranges, peaking at 3.1, 7.4 and 14.4 kHz. This partitioning between the two tympanal membranes constitutes an unusual feature of peripheral auditory processing in insects. The complex tracheal shape of O. uninotatus also deviates from the known tube or horn shapes associated with simple band-pass or high-pass amplification of tracheal input to the tympana. Interestingly, while the anterior tympanal membrane shows directional sensitivity at conspecific call frequencies, the posterior tympanal membrane is not directional at conspecific frequencies and instead shows directionality at higher frequencies.

}, keywords = {auditory, katydid, laser vibrometry, Onomarchus uninotatus, Orthoptera, pseudophylline, tettigoniid, trachea, tympanum}, doi = {10.1242/jeb.078352}, url = {http://jeb.biologists.org/cgi/doi/10.1242/jeb.078352https://syndication.highwire.org/content/doi/10.1242/jeb.078352}, author = {Rajaraman, K. and Mhatre, N. and Jain, M. and Postles, M. and Rohini Balakrishnan and Daniel Robert} } @article {53509, title = {Groups of bats improve sonar efficiency through mutual suppression of pulse emissions}, journal = {Frontiers in Physiology}, volume = {4}, year = {2013}, month = {Jan-01-2013}, abstract = {

How bats adapt their sonar behavior to accommodate the noisiness of a crowded day roost is a mystery. Some bats change their pulse acoustics to enhance the distinction between theirs and another bat\&$\#$39;s echoes, but additional mechanisms are needed to explain the bat sonar system\&$\#$39;s exceptional resilience to jamming by conspecifics. Variable pulse repetition rate strategies offer one potential solution to this dynamic problem, but precisely how changes in pulse rate could improve sonar performance in social settings is unclear. Here we show that bats decrease their emission rates as population density increases, following a pattern that reflects a cumulative mutual suppression of each other\&$\#$39;s pulse emissions. Playback of artificially-generated echolocation pulses similarly slowed emission rates, demonstrating that suppression was mediated by hearing the pulses of other bats. Slower emission rates did not support an antiphonal emission strategy but did reduce the relative proportion of emitted pulses that overlapped with another bat\&$\#$39;s emissions, reducing the relative rate of mutual interference. The prevalence of acoustic interferences occurring amongst bats was empirically determined to be a linear function of population density and mean emission rates. Consequently as group size increased, small reductions in emission rates spread across the group partially mitigated the increase in interference rate. Drawing on lessons learned from communications networking theory we show how modest decreases in pulse emission rates can significantly increase the net information throughput of the shared acoustic space, thereby improving sonar efficiency for all individuals in a group. We propose that an automated acoustic suppression of pulse emissions triggered by bats hearing each other\&$\#$39;s emissions dynamically optimizes sonar efficiency for the entire group.

}, doi = {10.3389/fphys.2013.00140}, url = {http://journal.frontiersin.org/article/10.3389/fphys.2013.00140/abstract}, author = {Jarvis, Jenna and Jackson, William and Smotherman, Michael} } @article {53338, title = {On the Design of a Bioacoustic Sensor for the Early Detection of the Red Palm Weevil}, journal = {Sensors}, volume = {13}, year = {2013}, month = {Jan-02-2013}, pages = {1706 - 1729}, abstract = {

During the last two decades Red Palm Weevil (RPW, Rynchophorus Ferrugineus) has become one of the most dangerous threats to palm trees in many parts of the World. Its early detection is difficult, since palm trees do not show visual evidence of infection until it is too late for them to recover. For this reason the development of efficient early detection mechanisms is a critical element of RPW pest management systems. One of the early detection mechanisms proposed in the literature is based on acoustic monitoring, as the activity of RPW larvae inside the palm trunk is audible for human operators under acceptable environmental noise levels (rural areas, night periods, etc.). In this work we propose the design of an autonomous bioacoustic sensor that can be installed in every palm tree under study and is able to analyze the captured audio signal during large periods of time. The results of the audio analysis would be reported wirelessly to a control station, to be subsequently processed and conveniently stored. That control station is to be accessible via the Internet. It is programmed to send warning messages when predefined alarm thresholds are reached, thereby allowing supervisors to check on-line the status and evolution of the palm tree orchards. We have developed a bioacoustic sensor prototype and performed an extensive set of experiments to measure its detection capability, achieving average detection rates over 90\%.

}, keywords = {acoustic sensor design, acoustic signal processing, pattern matching, pest detection, wavelet transform, wireless sensor networks}, doi = {10.3390/s130201706}, url = {http://www.mdpi.com/1424-8220/13/2/1706}, author = {Rach, Miguel and Gomis, H{\'e}ctor and Granado, Otoniel and Malumbres, Manuel and Campoy, Antonio and Mart{\'\i}n, Juan} } @article {53107, title = {Description of Acoustic Characters and Stridulatory Pars Stridens of Nicrophorus (Coleoptera: Silphidae): A Comparison of Eight North American Species}, journal = {Annals of the Entomological Society of America}, volume = {106}, year = {2013}, month = {Jan-09-2013}, pages = {661 - 669}, abstract = {

Insects make use of sound in a variety of behavioral and reproductive contexts. Acoustic signals are known to serve in defense, sexual advertisement, prey location, and in cooperative activities such as offspring care and group foraging. In airborne signals produced by insects, information associated with species identi\Þcation is often related to the temporal structure of the sound, while spectral quality is more closely associated with intraspeci\Þc variation. The Nicrophorine burying beetles (Insecta: Coleoptera: Silphidae) are a group known to produce sound through dorso-ventro stridulation, but the bioacoustics of this group remains understudied. Here, we examine the stridu- latory sound produced by eight North American species of Nicrophorus burying beetles, testing the hypothesis that interspeci\Þc differences will be encoded in temporal characteristics of the sound, and that signal divergence will be explained by one of three mechanisms: selection as an intraspeci\Þc signal, selection for interspeci\Þc aposematism, or random divergence through drift. We digitally recorded stridulation in each species, and analyzed recordings to describe each in respect to four spectral and eight temporal acoustic characters. All species produced a low amplitude biphastic sound pulse consisting of from 58 to 126 syllables, and exhibiting weak dominant frequencies (5.8\Ð12.7 kHz). Collapsing the 12 variables into three rotated factors using principal component analysis, we found no sex-related differences in sound, but signi\Þcant interspecies divergence in respect to all three factors. We constructed a phylogeny for the group based on the morphology of the stridulatory structures and the acoustic characters, and found weak support for an intraspeci\Þc signal divergence model.

}, keywords = {bioacoustics, burying beetle, Nicrophorus, sound production, stridulation}, issn = {00138746}, doi = {10.1603/AN13001}, url = {https://academic.oup.com/aesa/article-lookup/doi/10.1603/AN13001}, author = {Hall, Carrie L. and Mason, Andrew C. and Howard, Daniel R. and Padhi, Abinash and Smith, Rosemary J.} } @booklet {52845, title = {Further Progress in Computational Bioacoustics needs Open Access and Registry of Sound Files}, year = {2013}, abstract = {

Many\  papers\  on\  computational\  bioacoustics\  refer\  to\  recordings\  that\  are\  not\  publicly\  available.\  This\  practice\  is\  in\  stark\  contrast\  to\  other\  disciplines\  such\  as\  genetics,\  where\  deposition\  of\  sequences\  in\  publicly accessible databases is a prerequisite for publication in peer-reviewed journals.

}, doi = {10.13140/2.1.1862.4808}, url = {https://www.researchgate.net/publication/262723468_Further_Progress_in_Computational_Bioacoustics_needs_Open_Access_and_Registry_of_Sound_Files}, author = {Riede, Klaus and Olaf Jahn} } @article {52680, title = {The spider-like katydid Arachnoscelis (Orthoptera: Tettigoniidae: Listroscelidinae): anatomical study of the genus}, journal = {Zootaxa}, volume = {3666}, year = {2013}, month = {Apr-06-2013}, pages = {591}, abstract = {

This paper provides some observations on the anatomy of the neotropical katydid Arachnoscelis arachnoides Karny (In- secta: Orthoptera: Tettigoniidae). Arachnoscelis is a genus of predaceous katydids that comprise species that resemble spi- ders in their general body appearance. The type species, A. arachnoids, was described in 1891 from a single male collected in Colombia. Following the original description, these creatures were never found again, and were thought to have gone extinct or mistakenly assigned to the type locality. But between 1891 and 2012 four more species were described and in- correctly assigned to Arachnoscelis based on a similarity of body form. In this paper we present an anatomical comparai- son of Arachnoscelis and its relatives, and propose that Arachnoscelis should be treated as a monotypic genus. This implies that other species previously described in Arachnoscelis, should be placed in different genera.

}, keywords = {bushcricket, Colombia, predator, stridulation, ultrasound}, issn = {1175-5326}, doi = {10.11646/zootaxa.3666.410.11646/zootaxa.3666.4.11}, url = {http://biotaxa.org/Zootaxa/issue/view/zootaxa.3666.4}, author = {Montealegre-Z, Fernando and Cadena-Castaneda, Oscar J. and Benedict D. Chivers} } @mastersthesis {50740, title = {Investigating an adaptive radiation in temperate Neoconocephalus}, year = {2013}, school = {University of Missouri{\textendash}Columbia}, type = {phd}, author = {Frederick, Katherine H} } @article {48150, title = {The simple ears of noctuoid moths are tuned to the calls of their sympatric bat community}, journal = {Journal of Experimental Biology}, volume = {216}, year = {2013}, month = {Feb-04-20132149}, pages = {3954 - 3962}, abstract = {

nsects with bat-detecting ears are ideal animals for investigating sensory system adaptations to predator cues. Noctuid moths have two auditory receptors (A1 and A2) sensitive to the ultrasonic echolocation calls of insectivorous bats. Larger moths are detected at greater distances by bats than smaller moths. Larger moths also have lower A1 best thresholds, allowing them to detect bats at greater distances and possibly compensating for their increased conspicuousness. Interestingly, the sound frequency at the lowest threshold is lower in larger than in smaller moths, suggesting that the relationship between threshold and size might vary across frequencies used by different bat species. Here, we demonstrate that the relationships between threshold and size in moths were only significant at some frequencies, and these frequencies differed between three locations (UK, Canada and Denmark). The relationships were more likely to be significant at call frequencies used by proportionately more bat species in the moths\&$\#$39; specific bat community, suggesting an association between the tuning of moth ears and the cues provided by sympatric predators. Additionally, we found that the best threshold and best frequency of the less sensitive A2 receptor are also related to size, and that these relationships hold when controlling for evolutionary relationships. The slopes of best threshold versus size differ, however, such that the difference in threshold between A1 and A2 is greater for larger than for smaller moths. The shorter time from A1 to A2 excitation in smaller than in larger moths could potentially compensate for shorter absolute detection distances in smaller moths.

}, keywords = {allotonic frequency hypothesis, constant-frequency echolocation, horseshoe bats, predator{\textendash}prey interactions, sensory ecology}, issn = {0022-0949}, doi = {10.1242/jeb.093294}, url = {http://jeb.biologists.org/cgi/doi/10.1242/jeb.093294https://syndication.highwire.org/content/doi/10.1242/jeb.093294}, author = {ter Hofstede, H. M. and Goerlitz, H. R. and Ratcliffe, J. M. and Holderied, M. W. and Surlykke, A.} } @article {48149, title = {Interspecific acoustic recognition in two European bat communities}, journal = {Frontiers in Physiology}, volume = {4}, year = {2013}, month = {Jan-01-2013}, abstract = {

Echolocating bats emit echolocation calls for spatial orientation and foraging. These calls are often species-specific and are emitted at high intensity and repetition rate. Therefore, these calls could potentially function in intra- and/or inter-specific bat communication. For example, bats in the field approach playbacks of conspecific feeding buzzes, probably because feeding buzzes indicate an available foraging patch. In captivity, some species of bats recognize and distinguish the echolocation calls of different sympatric species. However, it is still unknown if and how acoustic species-recognition mediates interspecific interactions in the field. Here we aim to understand eavesdropping on bat echolocation calls within and across species boundaries in wild bats. We presented playbacks of conspecific and heterospecific search calls and feeding buzzes to four bat species with different foraging ecologies. The bats were generally more attracted by feeding buzzes than search calls and more by the calls of conspecifics than their heterospecifics. Furthermore, bats showed differential reaction to the calls of the heterospecifics. In particular, \<i\>Myotis capaccinii\</i\> reacted equally to the feeding buzzes of conspecifics and to ecologically more similar heterospecifics. Our results confirm eavesdropping on feeding buzzes at the intraspecific level in wild bats and provide the first experimental quantification of potential eavesdropping in European bats at the interspecific level. Our data support the hypothesis that bat echolocation calls have a communicative potential that allows interspecific, and potentially intraspecific, eavesdropping in the wild.

}, keywords = {acoustic communication, eavesdropping, echolocation, feeding buzz, interspecific communication, intraspecific communication, search calls}, doi = {10.3389/fphys.2013.00192}, url = {http://journal.frontiersin.org/article/10.3389/fphys.2013.00192/abstract}, author = {Dorado-Correa, Adriana M. and Goerlitz, Holger R. and Siemers, Bj{\"o}rn M.} } @article {48148, title = {Global warming alters sound transmission: differential impact on the prey detection ability of echolocating bats}, journal = {Journal of The Royal Society Interface}, volume = {11}, year = {2013}, month = {Feb-07-20132184}, abstract = {

Climate change impacts the biogeography and phenology of plants and ani- mals, yet the underlying mechanisms are little known. Here, we present a functional link between rising temperature and the prey detection ability of echolocating bats. The maximum distance for echo-based prey detection is physically determined by sound attenuation. Attenuation is more pronoun- ced for high-frequency sound, such as echolocation, and is a nonlinear function of both call frequency and ambient temperature. Hence, the prey detection ability, and thus possibly the foraging efficiency, of echolocating bats and susceptible to rising temperatures through climate change. Using present-day climate data and projected temperature rises, we modelled this effect for the entire range of bat call frequencies and climate zones around the globe. We show that depending on call frequency, the prey detection volume of bats will either decrease or increase: species calling above a cross- over frequency will lose and species emitting lower frequencies will gain prey detection volume, with crossover frequency and magnitude depending on the local climatic conditions. Within local species assemblages, this may cause a change in community composition. Global warming can thus directly affect the prey detection ability of individual bats and indirectly their interspecific interactions with competitors and prey.

}, keywords = {echolocation, foraging, global warming, sensory ecology, species interactions}, issn = {1742-5689}, doi = {10.1098/rsif.2013.0961}, url = {http://rsif.royalsocietypublishing.org/cgi/doi/10.1098/rsif.2013.0961https://syndication.highwire.org/content/doi/10.1098/rsif.2013.0961}, author = {Luo, J. and Koselj, K. and Zsebok, S. and Siemers, B. M. and Goerlitz, H. R.} } @article {48140, title = {Hawkmoths produce anti-bat ultrasound}, journal = {Biology Letters}, volume = {9}, year = {2013}, month = {Nov-20-20132082}, pages = {20130161 - 20130161}, abstract = {

Bats and moths have been engaged in aerial warfare for nearly 65 Myr. This arms race has produced a suite of counter-adaptations in moths, including bat-detecting ears. One set of defensive strategies involves the active production of sound; tiger moths\&$\#$39; ultrasonic replies to bat attack have been shown to startle bats, warn the predators of bad taste and jam their biosonar. Here, we report that hawkmoths in the Choerocampina produce entirely ultrasonic sounds in response to tactile stimulation and the playback of biosonar attack sequences. Males do so by grating modified scraper scales on the outer surface of the genital valves against the inner margin of the last abdominal tergum. Preliminary data indicate that females also produce ultrasound to touch and playback of echolocation attack, but they do so with an entirely different mechanism. The anti-bat function of these sounds is unknown but might include startling, cross-family acoustic mimicry, warning of unprofitability or physical defence and/or jamming of echolocation. Hawkmoths present a novel and tractable system to study both the function and evolution of anti-bat defences.

}, keywords = {arms race, bats, echolocation, Sphingidae, sphinx moth}, issn = {1744-9561}, doi = {10.1098/rsbl.2013.0161}, url = {http://rsbl.royalsocietypublishing.org/cgi/doi/10.1098/rsbl.2013.0161https://syndication.highwire.org/content/doi/10.1098/rsbl.2013.0161}, author = {Barber, J. R. and Kawahara, A. Y.} } @article {47758, title = {The bush-cricket Isophya kraussii (Orthoptera: Phaneropteridae): bioacoustics, distribution and description of a new subspecies from Romania}, journal = {Zootaxa}, volume = {3640}, year = {2013}, month = {May-04-2014}, pages = {258}, issn = {1175-5326}, doi = {10.11646/zootaxa.3640.210.11646/zootaxa.3640.2.8}, url = {http://biotaxa.org/Zootaxa/issue/view/zootaxa.3640.2}, author = {Ionut Stefan Iorgu and Klaus-Gerhard Heller} } @article {47755, title = {The Orthoptera (Insecta) from Middle and Lower Prut River Basin}, journal = {Travaux du Mus?um National d?Histoire Naturelle ?Grigore Antipa?}, volume = {56}, year = {2013}, month = {Jan-01-2013}, abstract = {

The ecological preferences and bioacoustics of bush-crickets, crickets and grasshoppers species were studied in middle and lower Prut River basin, a research conducted in 55 localities from Romania and 33 localities in the Republic of Moldova. A total number of 91 species of Orthoptera were collected in the study area: 85 species encountered on the western side of Prut River basin (9 Phaneropteridae, 24 Tettigoniidae, 1 Bradyporidae, 5 Gryllidae, 1 Gryllotalpidae, 1 Tridactylidae, 5 Tetrigidae, 39 Acrididae) and 76 species found on the eastern side (7 Phaneropteridae, 19 Tettigoniidae, 1 Bradyporidae, 5 Gryllidae, 1 Gryllotalpidae, 1 Tridactylidae, 3 Tetrigidae, 39 Acrididae). Four species are recorded for the first time in the Orthoptera fauna of the Republic of Moldova: Barbitistes constrictus (Fabricius), Poecilimon fussii Brunner von Wattenwyl, Metrioptera roeselii fedtschenkoi (Saussure) and Pholidoptera frivaldskyi (Herman).

}, keywords = {acoustics, biodiversity, distribution, Orthoptera, Prut}, doi = {10.2478/travmu-2013-0012}, url = {http://www.degruyter.com/view/j/travmu.2013.56.issue-2/travmu-2013-0012/travmu-2013-0012.xmlhttps://www.degruyter.com/view/j/travmu.2013.56.issue-2/travmu-2013-0012/travmu-2013-0012.pdf}, author = {Ionut Stefan Iorgu and Elena Iulia Iorgu and Stahi, Nadejda} } @article {47616, title = {Maintaining acoustic communication at a cocktail party: heterospecific masking noise improves signal detection through frequency separation}, journal = {Journal of Experimental Biology}, volume = {216}, year = {2013}, month = {Oct-24-20132050}, pages = {4655 - 4665}, abstract = {

We examined acoustic masking in a chirping katydid species of the Mecopoda elongata complex due to interference with a sympatric Mecopoda species where males produce continuous trills at high amplitudes. Frequency spectra of both calling songs range from 1 to 80 kHz; the chirper species has more energy in a narrow frequency band at 2 kHz and above 40 kHz. Behaviourally, chirper males successfully phase-locked their chirps to playbacks of conspecific chirps under masking conditions at signal-to- noise ratios (SNRs) of \−8 dB. After the 2 kHz band in the chirp had been equalised to the level in the masking trill, the breakdown of phase-locked synchrony occurred at a SNR of +7 dB. The remarkable receiver performance is partially mirrored in the selective response of a first-order auditory interneuron (TN1) to conspecific chirps under these masking conditions. However, the selective response is only maintained for a stimulus including the 2 kHz component, although this frequency band has no influence on the unmasked TN1 response. Remarkably, the addition of masking noise at 65 dB sound pressure level (SPL) to threshold response levels of TN1 for pure tones of 2 kHz enhanced the sensitivity of the response by 10 dB. Thus, the spectral dissimilarity between masker and signal at a rather low frequency appears to be of crucial importance for the ability of the chirping species to communicate under strong masking by the trilling species. We discuss the possible properties underlying the cellular/synaptic mechanisms of the \‘novelty detector\’.

}, keywords = {ambient noise, auditory interneuron, insects, katydid, novelty detection, selective encoding}, issn = {0022-0949}, doi = {10.1242/jeb.089888}, url = {http://jeb.biologists.org/cgi/doi/10.1242/jeb.089888https://syndication.highwire.org/content/doi/10.1242/jeb.089888}, author = {Siegert, M. E. and Heiner R{\"o}mer and Hartbauer, M.} } @article {47347, title = {Comments on the Malaysian Katydid Ancylecha fenestrata (Fabricius, 1793) (Orthoptera: Tettigoniidae)}, journal = {Entomologie heute}, volume = {25}, year = {2013}, pages = {57-75}, chapter = {57}, abstract = {

Ancylecha fenestrata is a rather large phaneropterine tettigoniid from Malaysia with leaf-like tegmina that are characterized by two crescent-like markings. This species is often raised in captivity, but publications about its biology are rare. Searching the internet we found several plants accepted for oviposition, but not for feeding. These plants have relatively fl eshy and leathery leaves and contain various substances (e. g. saponins, oxalic acid, speci fi c glucosides etc.) often harmful at least to verte- brates. Only a few plants appear to be used for both, egg deposition and feeding. Whether this is a strategy pursued by A. fenestrata in the wild, is unkown. Females oserved by us inserted up to 13 large kidney-shaped eggs (per leaf) in the leaf parenchyma of the Spotted Dracaena Dracaena surculosa often used for breeding. The chorion of the egg is composed of a thin, delicate outer layer that apparently forms a close association with the walls of the parenchyma cells of the leaf, followed by a broader spongy layer, a relatively thick and solid layer with dilatations (air spaces) connected by fi ne pore canals that also open out in the large spaces of the spongy layer, and a very thin basal layer. At temperatures of 22 to 25 \°C and relatively high humidities, nymphs hatch within 70 days on average. The fi rst nym- phal instars are strikingly multicoloured. In the resting position, in which the forelegs are extended forwards, the hind legs backwards, and the long antennae are hidden under the abdomen, they resem- ble spiders. Males and females of A. fenestrata produce sounds by tegminal stridulation. Stridulatory organs are sexually dimorphic. As typical for many tettigoniids, males possess a strongly sclerotized fi le with \“teeth\” ( pars stridens ) on the underside of the left tegmen base and on the upper surface a scraper ( plectrum ) near to the so-called mirror. Females lack a mirror possessing several small fi les with laterally cuspidate teeth on the upper surface of the right tegmen, whereas the underside of the left tegmen is not conspicuously modi fi ed. When disturbed, both sexes produce alarm or defence sounds.

}, keywords = {Ancylecha fenestrata, aposematism, chorion structure, reproduction, site of oviposition, stridulatory apparatus}, author = {Hartmut Greven and Sabrina Braatz and Dieter Schulten} } @article {47335, title = {The genus Aerotegmina (Orthoptera, Tettigoniidae, Hexacentrinae): chromosomes, morphological relations, phylogeographical patterns and description of a new species}, journal = {Organisms Diversity \& Evolution}, volume = {13}, year = {2013}, month = {Jan-12-2013}, pages = {521 - 530}, abstract = {

The genus Aerotegmina Hemp is common on East African mountains. Two species are known and a third, A. taitensis n. sp., is described in this paper. A. kilimandjarica Hemp is widespread while A. shengenae Hemp is endemic to the South Pare Mountains and A. taitensis n. sp. is known only from the Taita Hills. Morphologically, and from their song, A. shengenae and A. taitensis n. sp. are closely related. In chromosome number A. kilimandjarica (2n\ =\ 33) differs clearly from A. shengenae (2n\ =\ 27). Data presented on other flightless Orthoptera suggest that the South Pare Mountains and the Taita Hills, both belonging to the geologically old mountain chain of the Eastern Arc, show a faunistic similarity not shared by any other mountain range in the area. The mechanisms that led to this phylogeographic pattern in flightless Orthoptera in the Eastern Arc Mountains of northern Tanzania and southern Kenya and the inland volcanoes are discussed. A key to the three Aerotegmina species is presented, as well as bioacoustical data of all species compared to the phaneropterine species Euryastes jagoi.

}, keywords = {Aerotegmina, bioacoustics, chromosomes, East Africa, Eastern Arc Mountains, Euryastes, Hexacentrinae, morphology, new species, Orthoptera, phylogeography, Taita Hills}, issn = {1439-6092}, doi = {10.1007/s13127-013-0133-7}, url = {http://link.springer.com/10.1007/s13127-013-0133-7}, author = {Claudia Hemp and Klaus-Gerhard Heller and Warchalowska-Sliwa, Elzbieta and Hemp, Andreas} } @article {47334, title = {Biogeography, ecology, acoustics and chromosomes of East African Eurycorypha St{\r a}l species (Orthoptera, Phaneropterinae) with the description of new species}, journal = {Organisms Diversity \& Evolution}, volume = {13}, year = {2013}, month = {Jan-09-2013}, pages = {373 - 395}, abstract = {

Although Eurycorypha is the most species-rich Phaneropterinae genus in Africa, little is known about the distribution and the ecology of the species. In this study data on distribution, ecology, song and on chromosomes of some East African species are provided. The nymphs of some species are shown, famous for their ant-like appearance and behaviour. The male of E. punctipennis Chopard and three species of Eurycorypha are newly described. These are E. resonans n. sp. and E. combretoides n. sp. occurring in different habitats on Mount Kilimanjaro, and E. conclusa n. sp from forest habitats along the Tanzanian coast. Bioacoustically, the four recorded species are unusually divers, presenting non-resonant and resonant songs. As four Eurycorypha species occur syntopically on geological young Mount Kilimanjaro, the biogeographical pattern and possible speciation mechanisms in the genus Eurycorypha are discussed in context of the climatical history of eastern Africa.

}, keywords = {bioacoustics, Biogeography, chromosomes, ecology, Mount Kilimanjaro, new species, Orthoptera, Phaneropterinae, speciation, Tanzania}, issn = {1439-6092}, doi = {10.1007/s13127-012-0123-1}, url = {http://link.springer.com/10.1007/s13127-012-0123-1}, author = {Claudia Hemp and Klaus-Gerhard Heller and Warcha{\l}owska-{\'S}liwa, El{\.z}bieta and Grzywacz, Beata and Hemp, Andreas} } @article {47333, title = {Integrated systematics of the Poecilimon luschani species group (Orthoptera, Tettigoniidae): radiation as a chain of populations in a small heterogeneous area}, journal = {Zoological Journal of the Linnean Society}, volume = {169}, year = {2013}, month = {Jan-09-2013}, pages = {43 - 69}, abstract = {

The Poecilimon luschani species group (Orthoptera, Tettigonioidea, Phaneropterinae), ranging along a narrow line in West Anatolia and the Balkan mountains, has been revised using integrated data from morphology, bioacoustics, and DNA sequences of two matrilineal markers. A taxonomic approach neutral with respect to existing species/subspecies was applied to the sampled populations. The male calling song showed poor variation amongst the populations. Of the morphological structures, only the male cerci and male subgenital plate offer diagnostic characters but they are secondary gains or losses in most cases. Phylogenetic analyses applied to a data matrix consisting of concatenated 1401 bp long sequences of 16S rDNA and cytochrome oxidase subunit I produced from specimens of the group resulted in trees with similar topologies. Both genetic and phenotypic data confirmed the species status of the geographically discrete Izmir, Balkan, Ayd{\i}n, K\ütahya, and Bal{\i}kesir populations. However, 13 populations located in the southern part of the group\&$\#$39;s range in Antalya and Mu{\u g}la Provinces of Turkey present a complex phylogenetic and morphological pattern of three morphological units, but two phylogroups. By integrating song, morphology, and phylogenetic data the following conclusions were made. The species status of Poecilimon ledereri and Poecilimon orbelicus was confirmed. The Ayd{\i}n population was re-established as a valid species, P. tuncayi stat. rev. The K\ütahya population was elevated to species level as Poecilimon egrigozi \Ünal, 2005, stat. nov. The Bal{\i}kesir population is here described as a new species Poecilimon helleri sp. nov. The southern lineage of the species group exhibits characteristics of a chain species with three subspecies. Poecilimon luschani is retained as the species name by priority and the Poecilimon birandi is considered its subspecies as Poecilimon luschani birandistat. nov. A new subspecies Poecilimon luschani chobanovi ssp. nov. is described. The phylogenetic relationships amongst the proposed taxa are as follows: P. ledereri + (P. orbelicus + (P. tuncayi + (P. egrigozi + P. helleri) + (P. luschani luschani + P. luschani birandi + P. luschani chobanovi))).

}, keywords = {Anatolia, chain species, integrative taxonomy, Poecilimon luschani group}, doi = {10.1111/zoj.2013.169.issue-110.1111/zoj.12058}, url = {http://doi.wiley.com/10.1111/zoj.2013.169.issue-1https://academic.oup.com/zoolinnean/article-lookup/doi/10.1111/zoj.12058https://api.wiley.com/onlinelibrary/tdm/v1/articles/10.1111\%2Fzoj.12058}, author = {Boztepe, Zehra and Kaya, Sarp and {\c C}iplak, Battal} } @article {47330, title = {A taxonomic revision and species delimitation of the genus Purpuraria Enderlein, 1929 (Orthoptera: Pamphagidae) using an integrative approach}, journal = {Journal of Zoological Systematics and Evolutionary Research}, volume = {51}, year = {2013}, month = {Jan-08-2013}, pages = {173 - 186}, abstract = {

Recent studies on the endemic Canarian genus Purpuraria have shown that the taxonomy of its only recognized species (P. erna) is probably erroneous. In this study, an integrative revision of the genus is performed, based on a large number of specimens and geographical sampling. As a result, (1) the diagnostic characters at the genus level are re-described, (2) Purpuraria magna n. sp. based on morphological, morphometric and genetic data is described and (3) the taxonomic status of a formerly described subspecies is clarified. Intraspecific and interspecific morphometric differences have been found, indicating that the genus is undergoing a process of morphological diversification. Nevertheless, the possibility of interspecific mating between individuals of the two species is suggested, because no significant differences have been found between their respective calling songs. Genetic analyses using mitochondrial and nuclear DNA sequences suggest that P. erna and P. magna are recent species with evidences of secondary contact episodes in the past.

}, keywords = {bioacoustics, morphometrics, Pamphagidae, phylogeography, taxonomy}, doi = {10.1111/jzs.2013.51.issue-310.1111/jzs.12023}, url = {http://doi.wiley.com/10.1111/jzs.2013.51.issue-3}, author = {L{\'o}pez, Heriberto and Hern{\'a}ndez-Teixidor, David and Mac{\'\i}as-Hern{\'a}ndez, Nuria and Juan, Carlos and Orom{\'\i}, Pedro} } @article {47304, title = {Estimating animal population density using passive acoustics}, journal = {Biological Reviews}, volume = {88}, year = {2013}, month = {Jan-05-2013}, pages = {287 - 309}, abstract = {

Reliable estimation of the size or density of wild animal populations is very important for effective wildlife management, conservation and ecology. Currently, the most widely used methods for obtaining such estimates involve either sighting animals from transect lines or some form of capture-recapture on marked or uniquely identifiable individuals. However, many species are difficult to sight, and cannot be easily marked or recaptured. Some of these species produce readily identifiable sounds, providing an opportunity to use passive acoustic data to estimate animal density. In addition, even for species for which other visually based methods are feasible, passive acoustic methods offer the potential for greater detection ranges in some environments (e.g. underwater or in dense forest), and hence potentially better precision. Automated data collection means that surveys can take place at times and in places where it would be too expensive or dangerous to send human observers.

Here, we present an overview of animal density estimation using passive acoustic data, a relatively new and fast-developing field. We review the types of data and methodological approaches currently available to researchers and we provide a framework for acoustics-based density estimation, illustrated with examples from real-world case studies. We mention moving sensor platforms (e.g. towed acoustics), but then focus on methods involving sensors at fixed locations, particularly hydrophones to survey marine mammals, as acoustic-based density estimation research to date has been concentrated in this area. Primary among these are methods based on distance sampling and spatially explicit capture-recapture. The methods are also applicable to other aquatic and terrestrial sound-producing taxa.

We conclude that, despite being in its infancy, density estimation based on passive acoustic data likely will become an important method for surveying a number of diverse taxa, such as sea mammals, fish, birds, amphibians, and insects, especially in situations where inferences are required over long periods of time. There is considerable work ahead, with several potentially fruitful research areas, including the development of (i) hardware and software for data acquisition, (ii) efficient, calibrated, automated detection and classification systems, and (iii) statistical approaches optimized for this application. Further, survey design will need to be developed, and research is needed on the acoustic behaviour of target species. Fundamental research on vocalization rates and group sizes, and the relation between these and other factors such as season or behaviour state, is critical. Evaluation of the methods under known density scenarios will be important for empirically validating the approaches presented here.

}, keywords = {acoustic surveys, bioacoustics, density estimation, distance sampling, fixed sensors, hydrophones, passive acoustic monitoring, spatially explicit capture-recapture}, doi = {10.1111/brv.2013.88.issue-210.1111/brv.12001}, url = {http://doi.wiley.com/10.1111/brv.2013.88.issue-2}, author = {Marques, Tiago A. and Thomas, Len and Martin, Stephen W. and Mellinger, David K. and Ward, Jessica A. and Danielle V. Harris} } @article {16465, title = {Multimodal signaling in the Small Torrent Frog (Micrixalus saxicola) in a complex acoustic environment}, journal = {Behavioral Ecology and Sociobiology}, volume = {67}, year = {2013}, month = {Jan-09-2013}, pages = {1449 - 1456}, abstract = {

Many animals use multimodal (both visual and acoustic) components in courtship signals. The acoustic communication of anuran amphibians can be masked by the presence of environmental background noise, and multimodal displays may enhance receiver detection in complex acoustic environments. In the present study, we measured sound pressure levels of concurrently calling males of the Small Torrent Frog (Micrixalus saxicola) and used acoustic playbacks and an inflatable balloon mimicking a vocal sac to investigate male responses to controlled unimodal (acoustic) and multimodal (acoustic and visual) dynamic stimuli in the frogs\&$\#$39; natural habitat. Our results suggest that abiotic noise of the stream does not constrain signal detection, but males are faced with acoustic interference and masking from conspecific chorus noise. Multimodal stimuli elicited greater response from males and triggered significantly more visual signal responses than unimodal stimuli. We suggest that the vocal sac acts as a visual cue and improves detection and discrimination of acoustic signals by making them more salient to receivers amidst complex biotic background noise.

}, issn = {0340-5443}, doi = {10.1007/s00265-013-1489-6}, url = {http://link.springer.com/10.1007/s00265-013-1489-6}, author = {Preininger, Doris and Boeckle, Markus and Freudmann, Anita and Starnberger, Iris and Sztatecsny, Marc and H{\"o}dl, Walter} } @article {12627, title = {Data from: Open-ended song learning in a hummingbird.}, year = {2013}, publisher = {Dryad Digital Repository}, doi = {10.5061/dryad.vd61h}, author = {Araya-Salas, M. and Wright, T.} } @article {12626, title = {Open-ended song learning in a hummingbird}, journal = {Biology Letters}, volume = {9}, year = {2013}, month = {Oct-10-20132216}, pages = {20130625 - 20130625}, issn = {1744-9561}, doi = {10.1098/rsbl.2013.0625}, url = {http://rsbl.royalsocietypublishing.org/cgi/doi/10.1098/rsbl.2013.0625}, author = {Araya-Salas, M. and Wright, T.} } @book {12479, title = {Cicadas of Thailand Volume 2: Taxonomy and Sonic Ethology}, series = {Cicadas of Thailand}, volume = {2}, year = {2013}, publisher = {Siri Scientific Press}, organization = {Siri Scientific Press}, author = {Michel Boulard} } @article {11903, title = {Characterization and Generation of Male Courtship Song in Cotesia congregata (Hymenoptera: Braconidae)}, journal = {PLoS ONE}, volume = {8}, year = {2013}, month = {Oct-04-2014}, pages = {e62051}, abstract = {

Male parasitic wasps attract females with a courtship song produced by rapid wing fanning. Songs have been described for several parasitic wasp species; however, beyond association with wing fanning, the mechanism of sound generation has not been examined. We characterized the male courtship song of Cotesia congregata (Hymenoptera: Braconidae) and investigated the biomechanics of sound production. Courtship songs were recorded using high-speed videography (2,000 fps) and audio recordings. The song consists of a long duration amplitude-modulated \“buzz\” followed by a series of pulsatile higher amplitude \“boings,\” each decaying into a terminal buzz followed by a short inter-boing pause while wings are stationary. Boings have higher amplitude and lower frequency than buzz components. The lower frequency of the boing sound is due to greater wing displacement. The power spectrum is a harmonic series dominated by wing repetition rate ~220 Hz, but the sound waveform indicates a higher frequency resonance ~5 kHz. Sound is not generated by the wings contacting each other, the substrate, or the abdomen. The abdomen is elevated during the first several wing cycles of the boing, but its position is unrelated to sound amplitude. Unlike most sounds generated by volume velocity, the boing is generated at the termination of the wing down stroke when displacement is maximal and wing velocity is zero. Calculation indicates a low Reynolds number of ~1000. Acoustic pressure is proportional to velocity for typical sound sources. Our finding that the boing sound was generated at maximal wing displacement coincident with cessation of wing motion indicates that it is caused by acceleration of the wing tips, consistent with a dipole source. The low Reynolds number requires a high wing flap rate for flight and predisposes wings of small insects for sound production.

}, doi = {10.1371/journal.pone.0062051}, author = {Bredlau, Justin P. and Mohajer, Yasha J. and Cameron, Timothy M. and Kester, Karen M.}, editor = {Zeil, Jochen} } @article {11176, title = {True Katydids (Pseudophyllinae) from Guadeloupe: Acoustic Signals and Functional Considerations of Song Production}, journal = {Journal of Insect Science}, volume = {13}, year = {2013}, month = {Jan-12-2013}, pages = {1 - 16}, abstract = {

Guadeloupe, the largest of the Leeward Islands, harbors three species of Pseudophyllinae (Orthoptera: Tettigoniidae) belonging to distinct tribes. This study examined the basic aspects of sound production and acousto-vibratory behavior of these species. As the songs of many Pseudophyllinae are complex and peak at high frequencies, they require high quality recordings. Wild specimens were therefore recorded ex situ. Collected specimens were used in structure-function experiments. Karukerana aguilari Bonfils (Pterophyllini) is a large species with a mirror in each tegmen and conspicuous folds over the mirror. It sings 4\–6 syllables, each comprising 10\–20 pulses, with several peaks in the frequency spectrum between 4 and 20 kHz. The song is among the loudest in Orthoptera (\> 125 dB SPL in 10 cm distance). The folds are protective and have no function in song production. Both mirrors may work independently in sound radiation. Nesonotus reticulatus (Fabricius) (Cocconotini) produces verses from two syllables at irregular intervals. The song peaks around 20 kHz. While singing, the males often produce a tremulation signal with the abdomen at about 8\–10 Hz. To our knowledge, it is the first record of simultaneous calling song and tremulation in Orthoptera. Other males reply to the tremulation with their own tremulation. Xerophyllopteryx fumosa (Brunner von Wattenwyl) (Pleminiini) is a large, bark-like species, producing a syllable of around 20 pulses. The syllables are produced with irregular rhythms (often two with shorter intervals). The song peaks around 2\–3 kHz and 10 kHz. The hind wings are relatively thick and are held between the half opened tegmina during singing. Removal of the hind wings reduces song intensity by about 5 dB, especially of the low frequency component, suggesting that the hind wings have a role in amplifying the song.

}, keywords = {bioacoustics, bush-cricket, stridulation}, issn = {1536-2442}, doi = {10.1673/031.013.15701}, url = {http://www.bioone.org/doi/abs/10.1673/031.013.15701}, author = {Stumpner, Andreas and Dann, Angela and Schink, Matthias and Gubert, Silvia and Hugel, Sylvain} }