01070nas a2200145 4500008004100000022001300041245006600054210006400120260001600184300001400200490000700214520061500221100002200836856006600858 1971 eng d a0003347200aAggression in male conocephaline grasshoppers (tettigoniidae)0 aAggression in male conocephaline grasshoppers tettigoniidae cJan-02-1971 a132 - 1370 v193 a

Fighting occurs under field and laboratory conditions between conspecific males of the long horn grasshoppers O. gladiator, O. vulgare and C. nigropleurum. Approaches of 90 to 180 cm by Orchelimum males culminated in venter-to-venter grappling. Such fights usually ended in the silent withdrawal of one combatant, while the other initiated steady song from the encounter site. Only singing males were approached. Stridulation appears both to trigger the approach and to serve as a navigational aid during its excution. An area is maintained around dominating males that is free of conspecific signers.

1 aMorris, Glenn, K. uhttp://linkinghub.elsevier.com/retrieve/pii/S000334727180147102882nas a2200169 4500008004100000022001400041245011900055210006900174260001600243300001400259490000800273520231600281100002302597700002202620700002202642856004802664 1989 eng d a0340-759400aAuditory processing in the black-sided meadow katydid Conocephalus nigropleurum (Orthoptera: Tettigoniidae)0 aAuditory processing in the blacksided meadow katydid iConocephal cJan-01-1989 a501 - 5120 v1643 a

1. The auditory system of the tettigoniid,Conocephalus nigropleurum was examined using whole auditory nerve responses (averaged summed action potentials (SAPs)) and intracellularly recorded single cells (receptor and interneurone) to pure tone stimuli and con- and heterospecific (C. brevipennis) songs.

2.The morphology of the auditory tracheal system and crista acustica is documented forC. nigropleurum. A broadly open thoracic spiracle (stigma) leads, via a horn, camera and foreleg trachea to a crista acustica of 28 receptor cells.

3. C. nigropleurum's auditory sensitivity is broadly tuned to 15–35 kHz which is below the peak frequency band of its calling song (30–36 kHz). The ear possesses a dynamic range of at least 30 dB and pulsed sounds with short (<0.5 ms) onset times or long interpulse periods (>200 ms) elicit maximal responses. We suggest this is caused by increased auditory receptor firing synchrony to these types of sounds and may facilitate the location of such sounds. There is, however, discrepancy between the pulse periods that elicit maximal SAP amplitudes and those found within the normal calling song, a phenomenon which may be related to the chorusing behaviour of this species.

4.Polar directional plots indicate thatC. nigropleurum is most sensitive to sounds originating posterior to the opening of the prothoracic auditory stigma; this may be caused by the configuration of the prothoracic pronotum. We found no pronounced sensitivity at points facing the tympanal slits.

5.Intracellular recordings reveal prothoracic receptors with widely decussate and narrowly branched termini. No receptor tested was able to track the intra-phonatome pulses (tooth strike sounds) of either species and we conclude that the phonatome is the finest resoluble component of the song.

6. An acoustically-activated interneurone (101) was recorded that resembles both the gryllid int-2 (Omega) cell and that of another tettigoniid. We suggest that tonic interneuronal firing caused by the multiple singer chorused song of either species activates the initial stages of phonotaxis in receptiveC. nigropleurum females but individual species recognition may depend at least partially on the discrimination of phonatome rates.

1 aFullard, James, H.1 aMorris, Glenn, K.1 aMason, Andrew, C. uhttp://link.springer.com/10.1007/BF0061044401489nas a2200145 4500008004100000245012200041210006900163260001600232300001200248490000700260520096100267100002401228700002201252856006901274 1986 eng d00aConfusion of Phonotaxis by Masking Sounds in the Bushcricket Conocephalus brevipennis (Tettigoniidae: Conocephalinae)0 aConfusion of Phonotaxis by Masking Sounds in the Bushcricket Con cDec-01-1986 a19 - 280 v733 a

Female Conocephalus brevipennis, executing phonotaxis to the call of a conspecific male broadcast from a speaker, were subjected to varying levels of background sound so as to progressively mask the attracting signal. The background consisted of either random noise or the call of a sympatric congener, C. nigropleurum and was delivered from above the orienting female. Disruption of phonotaxis was assayed by monitoring the angular dispersion of the female's exit path from the arena, relative to the position of the conspecific call. Random noise significantly interfered with phonotaxis when it was within 2 dB of the conspecific call intensity, both signals measured at the centre of the arena. The equivalent effect of the call C. nigropleurum was 5 dB above conspecific call intensity. The implication of signal loss within background noise is discussed as are the possible interactive behaviours of competing sympatric syntopic species.

1 aBailey, Winston, J.1 aMorris, Glenn, K. uhttp://blackwell-synergy.com/doi/abs/10.1111/eth.1986.73.issue-1