00985nas a2200133 4500008004100000245012500041210007100166300001000237490000900247520051300256100002600769700001500795856004100810 2021 eng d00aPlatylomia kohimaensis n. sp.—a new cicada species (Hemiptera: Cicadidae) from the Naga Hills in the Eastern Himalayas0 aPlatylomia kohimaensis n sp—a new cicada species Hemiptera Cicad a81-910 v50473 a

A new cicada species, Platylomia kohimaensis n. sp., belonging to the Platylomia radha group is described from the Naga Hills in the eastern Himalayas. It is a dusk singing, large-sized cicada that calls for a short window during the evening twilight hours. Timbalisation is in the form of a continuous and regular cackling. Photographs of adult male and female along with genitalia illustration and distribution map are provided. A sonogram along with Acoustic Identification Card is also provided.

1 aHajong, Sudhanya, Ray1 aLimatemjen uhttps://bio.acousti.ca/sv/node/5843801733nas a2200169 4500008004100000022001400041245008900055210006900144260001600213300001600229490000800245520119600253100001801449700002601467700001901493856005101512 2010 eng d a0001-496600aSound emission and reception tuning in three cicada species sharing the same habitat0 aSound emission and reception tuning in three cicada species shar cJan-03-2010 a1681 - 16880 v1273 a

Many animal species acoustically communicate at the same place and time generating complex acoustic environments. However, the acoustic parameter space is usually structured, with each species emitting identifiable signals. While signal partitioning has been reported, very few analyses include the mechanical spectral response of auditory organs. The loud chorus generated by . The vibration pattern of L. plebejus shows traveling waves as previously observed in Ctra. atra. The spectral properties of both calling songs and tympanal auditory systems primarily indicate that each species uses its own frequency band.y, except for C. orni, which is sensitive to the lowest frequency band of its song. In contrast, female TMs are broadly tuned to the male songs. Ctra. atra females differ by tuning to frequencies slightly higher than the male song. Hence, acoustic space partitioning occurs for both emitter and receiver, but does not seem to fully preclude interference risk as some spectral overlap exists. In addition to the local physical ecology of each species, selective attention to conspecific signals is likely to be enhanced by further mechanical and neuronal processing.

1 aSueur, Jerome1 aWindmill, James, F.C.1 aRobert, Daniel uhttp://asa.scitation.org/doi/10.1121/1.329103601942nas a2200205 4500008004100000245008000041210006900121520124300190653001701433653001201450653002901462653002101491653001401512653002101526653001301547100001401560700002701574700001501601856012001616 2008 eng d00aSexual dimorphism in auditory mechanics: tympanal vibrations of Cicada orni0 aSexual dimorphism in auditory mechanics tympanal vibrations of C3 a

In cicadas, the tympanum is anatomically intricate and employs complex vibrations as a mechanism for auditory frequency analysis. Using microscanning laser Doppler vibrometry, the tympanal mechanics of Cicada orni can be characterized in controlled acoustical conditions. The tympanum of C. orni moves following a simple drum-like motion, rather than the travelling wave found in a previous study of Cicadatra atra. There is a clear sexual dimorphism in the tympanal mechanics. The large male tympanum is unexpectedly insensitive to the dominant frequency of its own calling song, possibly a reflection of its dual purpose as a sound emitter and receiver. The small female tympanum appears to be mechanically sensitive to the dominant frequency of the male calling song and to high-frequency sound, a capacity never suspected before in these insects. This sexual dimorphism probably results from a set of selective pressures acting in divergent directions, which are linked to the different role of the sexes in sound reception and production. These discoveries serve to indicate that there is far more to be learnt about the development of the cicada ear, its biomechanics and evolution, and the cicada's acoustic behaviour.

10abiomechanics10ahearing10ahigh-frequency reception10alaser vibrometry10apredation10aselective forces10atympanum1 aSueur, J.1 aWindmill, James, F. C.1 aRobert, D. uhttp://jeb.biologists.org/cgi/doi/10.1242/jeb.018804https://syndication.highwire.org/content/doi/10.1242/jeb.01880401726nas a2200193 4500008004100000245008300041210006900124520106900193653001201262653001701274653001101291653002901302653001201331653001301343100002701356700001401383700001501397856012001412 2009 eng d00aThe next step in cicada audition: measuring pico-mechanics in the cicada's ear0 anext step in cicada audition measuring picomechanics in the cica3 a

Female cicadas use sound when they select a mate from a chorus of singing males. The cicada has a tympanal ear; and the tympanal membrane, and constituent tympanal ridge, act as both acousto-mechanical transducers and frequency filters. The tympanal ridge is physically connected to a large number of mechanoreceptor neurons via a cuticular extension known as the tympanal apodeme. Using microscanning laser Doppler vibrometry, we measured for the first time the in vivo vibrations of the apodeme of female Cicadatra atra in response to the motion of the tympanum driven by sound. These measurements reveal that the nanoscale motion of the tympanal membrane is over a magnitude greater than that of the apodeme. Furthermore, the apodeme acts as an additional mechanical frequency filter, enhancing that of the tympanal ridge, narrowing the frequency band of vibration at the mechanoreceptor neurons to that of the male calling song. This study enhances our understanding of the mechanical link between the external ear of the cicada and its sensory cells.

10aapodeme10abiomechanics10aCicada10afrequency discrimination10ahearing10atympanum1 aWindmill, James, F. C.1 aSueur, J.1 aRobert, D. uhttp://jeb.biologists.org/cgi/doi/10.1242/jeb.033019https://syndication.highwire.org/content/doi/10.1242/jeb.03301901885nas a2200193 4500008004100000245009700041210006900138520127800207653001701485653001101502653002901513653001201542653002001554653001301574100001801587700002601605700001901631856004101650 2006 eng d00aTuning the drum: the mechanical basis for frequency discrimination in a Mediterranean cicada0 aTuning the drum the mechanical basis for frequency discriminatio3 a

Cicadas are known to use sound to find a mate. While the mechanism employed by male cicadas to generate loud calling songs has been described in detail, little information exists to explain how their ears work. Using microscanning laser Doppler vibrometry, the tympanal vibrations in the cicada Cicadatra atra are measured in response to acoustic playbacks. The topographically accurate optical measurements reveal the vibrational behaviour of the anatomically complex tympanal membrane. Notably, the tympanal ridge, a distinct structural element of the tympanum that is a link to the receptor cells, undergoes mechanical vibrations reminiscent of a travelling wave. In effect, the frequency for which the maximum deflection amplitude is observed regularly decreases from the apex to the base of the ridge. It is also shown that whilst female ears are mechanically tuned to the male's song, the male's tympanum is only partially tuned to its own song. This study establishes the presence of a peripheral auditory mechanism that can potentially process auditory frequency analysis. In view of the importance of acoustic signalling in cicadas, this unconventional tympanal mechanism may be employed in the context of species recognition and sexual selection.

10abiomechanics10aCicada10afrequency discrimination10ahearing10atravelling wave10atympanum1 aSueur, Jerome1 aWindmill, James, F.C.1 aRobert, Daniel uhttps://bio.acousti.ca/sv/node/5762202420nas a2200313 4500008004100000022001400041245014400055210006900199260001600268300001200284490000700296520152100303653001101824653001101835653001201846653001801858653001601876653002101892653001601913653001001929653001501939653001501954653001201969100001701981700001901998700001802017700002002035856005102055 2008 eng d a0006-897700aAuditory Sensitivity of an Acoustic Parasitoid (Emblemasoma sp., Sarcophagidae, Diptera) and the Calling Behavior of Potential Hosts0 aAuditory Sensitivity of an Acoustic Parasitoid iEmblemasomai sp  cJan-01-2008 a16 - 260 v723 a

Using field broadcasts of model male calling songs, we tested whether Tibicen pruinosa and T. chloromera (Homoptera: Cicadidae) are candidate hosts for acoustic parasitoid flies. The model calling song of T. pruinosa attracted 90% of the flies (Sarcophagidae: Emblemasoma sp.; all larvapositing females) when broadcast simultaneously with the model T. chloromera song, a phonotactic bias reconfirmed in single song playbacks. In paired broadcasts of model T. pruinosa songs with different relative amplitudes (3 dB or 6 dB), significantly more flies were attracted to the more powerful song, a result consistent with the responses predicted by a model proposed by Forrest and Raspet [1994]. Using intracellular recordings and dye injections, we characterized the sensitivity of auditory units in sound-trapped flies. Intracellular recordings from six auditory units (5 interneurons, 1 afferent) revealed best sensitivity for frequencies near 3-4 kHz, matching the predominant spectral components of the calling songs of both species of cicada. Interestingly, although flies could be attracted to T. pruinosa broadcasts throughout the day, hourly censuses of singing males revealed that calling occurred exclusively at dusk. Furthermore, the duration of the dusk chorus in T. pruinosa was significantly shorter than the midday chorus of the less attractive song of T. chloromera. We propose that the tight temporal aggregation of the dusk chorus time could function to reduce risk from attracted parasitoids.

10aChorus10aCicada10acricket10aDiel Behavior10aEmblemasoma10afrequency tuning10ainterneuron10aOrmia10aparasitoid10aphonotaxis10aTibicen1 aFarris, H.E.1 aOshinsky, M.L.1 aForrest, T.G.1 aHoy, Ronald, R. uhttps://www.karger.com/Article/FullText/13945801415nas a2200157 4500008004100000245021500041210006900256260001600325520078600341653001701127653001101144653002501155653001301180100002101193856004301214 2017 eng d00aCaledopsalta gen. nov., a new genus for the New Caledonian cicadas previously assigned to Pauropsalta Goding & Froggatt, plus the description of four new species (Hemiptera: Cicadoidea: Cicadidae)0 aiCaledopsaltai gen nov a new genus for the New Caledonian cicada cMay-08-20183 a

Species currently assigned to Pauropsalta Goding & Froggatt in New Caledonia are reviewed. Molecular and morphological studies indicate that New Caledonian cicadas placed in this genus belong in a different genus. The genus Caledopsalta gen. nov. is therefore erected to accommodate Caledopsalta johanae comb. nov., and Caledopsalta judithae. comb. nov., as well as the following four new species: Caledopsalta ouitchamboensis sp. nov., C. canteminvantum sp. nov., C. garrula sp. nov. and C. sciaphila sp. nov. Male calling songs of all species are analysed and described from field recordings. A key to the species of Caledopsalta gen. nov. is provided. This new genus is included within the tribe Cicadettini, with Pauropsalta johanae designated as the type species.

10abioacoustics10aCicada10ashort-range endemism10ataxonomy1 aDelorme, Quentin uhttp://doi.wiley.com/10.1111/aen.1229501571nas a2200229 4500008004100000022001400041245017200055210006900227260001600296300000800312490000900320520078600329653002201115653001601137653001801153653002801171653001901199653001501218100002401233700002301257856006101280 2017 eng d a1175-532600aA new Neotibicen cicada subspecies (Hemiptera: Cicadidae) from the southeastern USA forms hybrid zones with a widespread relative despite a divergent male calling song0 anew Neotibicen cicada subspecies Hemiptera Cicadidae from the so cJul-05-2019 a5290 v42723 a

A morphologically cryptic subspecies of Neotibicen similaris (Smith and Grossbeck) is described from forests of the Apalachicola region of the southeastern United States. Although the new form exhibits a highly distinctive male calling song, it hybridizes extensively where it meets populations of the nominate subspecies in parapatry, by which it is nearly surrounded. This is the first reported example of hybridization between North American nonperiodical cicadas. Acoustic and morphological characters are added to the original description of the nominate subspecies, and illustrations of complex hybrid song phenotypes are presented. The biogeography of N. similaris is discussed in light of historical changes in forest composition on the southeastern Coastal Plain.

10aacoustic behavior10ahybrid zone10ahybridization10aparapatric distribution10asexual signals10aspeciation1 aMarshall, David, C.1 aHill, Kathy, B. R. uhttp://www.biotaxa.org/Zootaxa/issue/view/zootaxa.4272.401489nas a2200157 4500008004100000022001400041245014400055210006900199260001600268300001400284490000700298520094300305100001401248700001401262856005501276 2003 eng d a0028-104200aIs microhabitat segregation between two cicada species ( Tibicina haematodes and Cicada orni ) due to calling song propagation constraints?0 amicrohabitat segregation between two cicada species Tibicina hae cJan-07-2003 a322 - 3260 v903 a

The cicada species Tibicina haematodes and Cicada orni are two sympatric species often inhabiting vineyards. We show that they occupy two distinct levels: males of T. haematodes produce their calling songs from a high position in vine foliage while males of C. orni call from a low position near the ground on vine trunks. Experiments consisting of broadcasting and re-recording experimental signals in natural habitats from low and high positions show that signals are more and more modified as sender–receiver distance increases. T. haematodes would have an advantage when calling on trunks rather than on branches whereas C. orni would be able to call indiscriminately from both low and high positions. Thus, the microhabitat segregation observed between T. haematodes and C orni in vineyards does not seem to be related to calling song propagation constraints, but may be due to other ethological or ecological factors.

1 aSueur, J.1 aAubin, T. uhttp://link.springer.com/10.1007/s00114-003-0432-502216nas a2200289 4500008004100000022001400041245018900055210006900244260001600313300000800329490000900337520126200346653001101608653001401619653001201633653001401645653001601659100002601675700002001701700002201721700001901743700002601762700002801788700002401816700002901840856005701869 2017 eng d a1175-532600aMorphology, songs and genetics identify two new cicada species from Morocco: Tettigettalna afroamissa sp. nov. and Berberigetta dimelodica gen. nov. & sp. nov. (Hemiptera: Cicadettini)0 aMorphology songs and genetics identify two new cicada species fr cJan-03-2017 a5170 v42373 a

Morocco has been the subject of very few expeditions on the last century with the objective of studying small cicadas. In the summer of 2014 an expedition was carried out to Morocco to update our knowledge with acoustic recordings and genetic data of these poorly known species. We describe here two new small-sized cicadas that could not be directly assigned to any species of North African cicadas: Tettigettalna afroamissa sp. nov. and Berberigetta dimelodica gen. nov. & sp. nov. In respect to T. afroamissa it is the first species of the genus to be found outside Europe and we frame this taxon within the evolutionary history of the genus. Acoustic analysis of this species allows us to confidently separate T. afroamissa from its congeners. With B. dimelodica, a small species showing a remarkable calling song characterized by an abrupt frequency modulation, a new genus had to be erected. Bayesian inference and maximum likelihood phylogenetic analyses with DNA-barcode sequences of Cytochrome C Oxidase 1 support the monophyly of both species, their distinctness and revealed genetic structure within B. dimelodica. Alongside the descriptions we also provide GPS coordinates of collection points, distributions and habitat preferences

10aCicada10aHemiptera10aMorocco10anew genus10anew species1 aCosta, Gonçalo João1 aNunes, Vera, L.1 aMarabuto, Eduardo1 aMendes, Raquel1 aLaurentino, Telma, G.1 aQuartau, José, Alberto1 aPAULO, OCTÁVIO, S.1 aSimões, Paula, Cristina uhttp://biotaxa.org/Zootaxa/issue/view/zootaxa.4237.301569nas a2200193 4500008004100000022001400041245011800055210006900173260001600242300000800258490000900266520093300275653001701208653001201225653003301237653002601270100002201296856005701318 2017 eng d a1175-532600aA new species of Megatibicen endemic to Mescalero-Monahans shinnery sands (Hemiptera: Auchenorrhyncha: Cicadidae)0 anew species of Megatibicen endemic to MescaleroMonahans shinnery cNov-02-2018 a5530 v42363 a

Megatibicen harenosus sp. n. is described from the Mescalero-Monahans shinnery sands of New Mexico and Texas, U.S.A. The new species is diagnosed from similar species, especially M. tremulus which it resembles closely, by male genital morphology, color pattern, calling song, and ecology. Seven characters from the male calling song are described from analysis of field recordings, of which all four temporal song characters are significantly different from M. tremulus. With one of the most southwestern distribution of any Megatibicen species, M. harenosus is a new addition to the rich, endemic, and understudied Mescalero-Monahans shinnery sands biota. The possibility that M. harenosus and M. tremulus are sister species is raised. The ecological, biological, and evolutionary species concepts support species status for M. harenosus, and an hypothesis of peripatric speciation in peripheral isolation is advanced.

10abioacoustics10aendemic10aevolutionary species concept10aperipatric speciation1 aCole, Jeffrey, A. uhttp://biotaxa.org/Zootaxa/issue/view/zootaxa.4236.302759nas a2200133 4500008004100000245006000041210005800101300001200159490000800171520236000179100002502539700001302564856004802577 1992 eng d00aA MODEL OF THE MECHANISM OF SOUND PRODUCTION IN CICADAS0 aMODEL OF THE MECHANISM OF SOUND PRODUCTION IN CICADAS a123-1530 v1733 a

1. Dried cicada bodies of the species Cyclochila australasiae and model cicadas made from a miniature earphone driving a plastic cavity were used to study the acoustics of sound production in male cicadas.

2. A model cicada with shape and dimensions similar to those of the abdomen of a male C. australasiae resonates at the natural song frequency of the species (4.3 kHz). The abdominal air sac of C. australasiae also resonates at frequencies close to the natural song frequency when excited by external sounds. In an atmosphere of chlorofluorocarbon (CFC) gas, the resonant frequency is lowered in keeping with the decrease in velocity of sound in the CFC gas.

3. At the model's resonant frequency, the driving earphone dissipates more electrical power with the cavity attached than without the cavity. The cavity of the model cicada acts as a narrow-band acoustic acceptance filter, tuned to the natural song frequency.

4. When the miniature earphone emits brief clicks, mimicking those produced by the natural tymbal mechanism, the model cicada produces sound pulses that vary in duration and shape according to the number and timing of the clicks. A coherent train of two or three resonant clicks results in a long slowly-decaying sound pulse similar to that in the natural song.

5. The natural song frequency can be predicted from the dimensions of the abdominal cavity and the tympana in C. australasiae using a simple equation for the resonant frequency of a Helmholtz resonator. This equation also predicts the song frequency of Macrotristria angularis and Magicicada cassini, but it fails with the low-frequency song of Magicicada septendecim. This discrepancy can be accounted for by the unusually thick tympana of M. septendecim, which tend to lower the resonant frequency of the system.

6. We conclude that the abdomen of male cicadas forms a Helmholtz resonator, the components of which are the large air sac as the cavity and the tympana as the neck of the resonator. We suggest that cicada sound production depends on the coupling of two resonators, that of the tymbal and that of the abdominal air sac, from which sound is radiated through the tympana. The coupled resonator system would produce the long sound pulses required for stimulating a sensitive sharply tuned auditory organ.

1 aBennet-Clark, H., C.1 aYoung, D uhttp://jeb.biologists.org/content/173/1/12303995nas a2200145 4500008004100000022001400041245009300055210006900148260000900217300001200226490000800238520352300246100002503769856005503794 1997 eng d a1477-914500aTymbal mechanics and the control of song frequency in the cicada Cyclochila australasiae0 aTymbal mechanics and the control of song frequency in the cicada c1997 a1681-940 v2003 a

The anatomy of the tymbal of Cyclochila australasiae was re-described and the mass of the tymbal plate, ribs and resilin pad was measured. The four ribs of the tymbal buckle inwards in sequence from posterior to anterior. Sound pulses were produced by pulling the tymbal apodeme to cause the tymbal to buckle inwards. A train of four sound pulses, each corresponding to the inward buckling of one rib, could be produced by each inward pull of the apodeme, followed by a single pulse as the tymbal buckled outwards after the release of the apodeme. Each preparation produced a consistent sequence of pulses. Each of the pulses produced had its maximum amplitude during the first cycle of vibration. The waveform started with an initial inward-going rarefaction followed by a larger outward compression, followed by an approximately exponential decay, as is typical of a resonant system. The mean dominant frequencies of the pulses produced during the inward movement were 4.37, 4.19, 3.92 and 3.17 kHz respectively. The pulse produced during the outward movement had a mean resonant frequency of 6.54 kHz. This suggests that the mass-to-stiffness ratio that determines the resonant frequencies of the various pulses differs from pulse to pulse. If succeeding pulses followed rapidly, the next pulse tended to start on the inward-going half-cycle of its predecessor and to produce a coherent waveform. Coherence was lost if the preceding pulse had decayed to below approximately one-tenth of its peak amplitude. When the tymbal plate was loaded by a 380 µg wire weight, the resonant frequency of all sound pulses was reduced. Pulses produced later in the inward buckling sequence were less affected by the loading than earlier ones. This suggests that the effective mass determining the resonance in the later pulses is greater than that in the earlier pulses. The frequency of the pulses produced in the outward movement was affected most, suggesting that the mass involved was less than that in any of the pulses produced by the inward movement. The quality factor, Q, of the pulses produced by the inward buckling of the unloaded tymbal was approximately 10. For the outward buckling, Q was approximately 6. The Q of loaded tymbals was higher than than that of unloaded tymbals. The Q of the resonances varied approximately as the reciprocal of the resonant frequency. Experimental removal of parts of the tymbal showed that the thick dorsal resilin pad was an important elastic determinant of the resonant frequency, but that the mass and elasticity of the tymbal ribs were also determinants of the resonant frequency. The major element of mass is the tymbal plate. The integrity of the tymbal ribs was essential if the buckling movement were to occur. The force required to cause inward buckling of the tymbal was approximately 0.25 N. The force required to hold the tymbal in the buckled-in position was approximately 0.05 N. This asymmetry in the tymbal compliance, together with the different masses involved in inward and outward buckling, may account for the difference between the resonant frequencies of the inward-going and outward-going clicks. The tymbal appears to act as an energy storage mechanism that releases energy as the tymbal ribs buckle inwards in sequence. Each pulse provides a large initial impulse to the abdominal resonator, followed by a sustaining resonant vibration at, or close to, the song frequency. Subsequent pulses maintain the coherent resonance of the song pulse.

1 aBennet-Clark, H., C. uhttp://jeb.biologists.org/content/200/11/1681.long02247nas a2200157 4500008004100000022001400041245009400055210006900149260001300218300001200231490001600243520173700259100002501996700001302021856005502034 1999 eng d a1477-914500aTransduction of mechanical energy into sound energy in the cicada Cyclochila australasiae0 aTransduction of mechanical energy into sound energy in the cicad c1999 Jul a1803-170 v202 (Pt 13)3 a

The anatomy of the paired tymbal muscles of Cyclochila australasiae was described. Force-distance relationships of the sound-producing in-out cycle of tymbal movement were measured. The largest forces were measured when the push occurred at the apodeme pit on the tymbal plate at angles similar to the angles of internal pull of the tymbal muscle. Initially, inward movement was opposed by the elasticity of the tymbal, which stored energy. At a mean force of 0. 38 N after a mean inward strain of 368 microm, the tymbal ribs buckled, the mean energy release being 45.1 microJ. The energy release occurred over 2-10 ms in three or four sound-producing steps as successive tymbal ribs buckled inwards. After the ribs had buckled, the force decreased to a mean value of 0.17 N. The force returned to zero during the outward movement, during which the tymbal ribs buckled outwards. The mean energy dissipated in the outward movement was 32.8 microJ. During contraction, the tymbal muscle produced mean values for the peak active force of 0.31 N over 295 microm, which gave mean values for the area of the work loops of 47.0 microJ. The calling song of C. australasiae had a mean pulse rate of 234 Hz (117 Hz for each side of the insect). The peak power to mean power ratio for the songs was 8.51:1 (+9.30 dB). Measurements of the sound field around tethered insects and of the peak power to mean power ratio of the songs gave values for the mean power of the song of 3.15-7 mW; these correspond to an energy per song pulse of 13.5-30 microJ. Previously reported mean values are 3. 15 mW for protest song and 5.1 mW for calling song. The efficiency of transduction of mechanical energy into sound energy is between 18 and 46 %.

1 aBennet-Clark, H., C.1 aDaws, AG uhttp://jeb.biologists.org/content/202/13/1803.long03608nas a2200157 4500008004100000022001400041245005400055210005000109260000900159300001200168490000800180520318300188100001303371700002503384856004103409 1995 eng d a1477-914500aThe role of the tymbal in cicada sound production0 arole of the tymbal in cicada sound production c1995 a1001-200 v1983 a

1. The tymbal of Cyclochila australasiae consists of a biconvex membrane bearing alternating long and short ribs anteriorly and an irregularly shaped tymbal plate posteriorly. These sclerotised regions are coupled together by the surrounding highly flexible cuticle, which contains resilin. Dorsally, there is a thick pad of resilin, which functions as a spring, returning the tymbal to the out position and maintaining the stress on the long ribs. 2. Contraction of the tymbal muscle causes the tymbal plate to swing inwards, acting as a lever so that the surface of the tymbal moves through more than twice the distance of muscle shortening. This produces an inward movement and twisting of the dorsal ends of the long ribs, which then buckle in sequence, with each rib undergoing a sudden deformation from a convex to a V-shaped profile. Buckling takes place at the rib's weakest point, which is the narrow, highly sclerotised mid-region. 3. Inward buckling of the tymbal generates a loud click with a dominant frequency around 4 kHz. Resonances close to 4 kHz can be demonstrated in a buckled-in tymbal when driven by internal sound or by vibration at the tymbal plate. These resonances occur in sealed cicadas and those in which the abdominal air sac has been opened at both its anterior and posterior ends, which shows that the resonances are not due to the air sac; the tymbal itself is a resonant system. The maximum amplitude of tymbal vibration occurs at the V-shaped dimples in the centre of the long ribs. 4. When the tymbal plus abdominal air sac system is driven by vibration at the tymbal plate, the Q3dB of the sound radiated through the tympana is about 12.5, which is approximately the sum of those of the tymbal (Q=9.3) and of the air sac (Q=3.4) resonators. When the tymbal is not loaded by the air sac, i.e. in the sealed cicada and open cicada preparations, the Q3dB of its resonance is higher, between 13 and 20. 5. The click produced as the tymbal pops out is over 20 dB quieter than the in-click and has a dominant frequency around 6 kHz. When driven in the resting position, resonances are found close to 6 kHz but there is only a weak general vibration of the ribs and tymbal plate. When the tymbal is pushed in gradually, the resonant frequency changes from about 5.5 kHz to about 4.3 kHz as the tymbal buckles inwards. The left and right tymbals of the same insect may differ slightly in their acoustic properties. 6. As the tymbal buckles inwards, it displaces a volume of approximately 6 µl into the abdominal air sac volume of about 2 ml. The resulting sound pressure inside the air sac attains peak values of 155­159 dB SPL; the root mean square values are 141­144 dB SPL. The mean peak value just outside the tympana is 148.5 dB SPL. 7. Overall, the present work supports and extends our earlier model of cicada sound production: the tymbal click provides a coherent resonant source that drives the abdominal resonator, from which sound is radiated via the tympana. At the same time, the system provides the pressure transformation between muscle power and sound power that is desirable for efficient sound radiation.

1 aYoung, D1 aBennet-Clark, H., C. uhttps://bio.acousti.ca/sv/node/1720802128nas a2200217 4500008004100000245018900041210006900230300001400299490000700313520129700320653001301617653001901630653002301649653002101672653001501693653001501708100001901723700001901742700002301761856012601784 2007 eng d00aPatterns and processes underlying evolutionary significant units in the Platypleura stridula L. species complex (Hemiptera: Cicadidae) in the Cape Floristic Region, South Africa0 aPatterns and processes underlying evolutionary significant units a2574-25880 v163 a

Cicadas have been shown to be useful organisms for examining the effects of distribution, plant association and geographical barriers on gene flow between populations. The cicadas of the Platypleura stridula species complex are restricted to the biologically diverse Cape Floristic Region (CFR) of South Africa. They are thus an excellent study group for eluci- dating the mechanisms by which hemipteran diversity is generated and maintained in the CFR. Phylogeographical analysis of this species complex using mitochondrial DNA Cytochrome Oxidase I (COI) and ribosomal 16S sequence data, coupled with preliminary morphological and acoustic data, resolves six clades, each of which has specific host-plant associations and distinct geographical ranges. The phylogeographical structure implies simultaneous or near-simultaneous radiation events, coupled with shifts in host-plant associations. When calibrated using published COI and 16S substitution rates typical for related insects, these lineages date back to the late Pliocene – early Pleistocene, coincident with vegetation change, altered drainage patterns and accelerated erosion in response to neotectonic crustal uplift and cyclic Pleistocene climate change, and glaciation-associated changes in climate and sea level.

10aendemism10aphylogeography10aplant associations10asea-level change10aspeciation10avicariance1 aPrice, Ben, W.1 aBarker, N., P.1 aVillet, Martin, H. uhttps://bio.acousti.ca/sv/content/patterns-and-processes-underlying-evolutionary-significant-units-platypleura-stridula-l