黑蚱蝉的叫声模式和神经肌肉活动特性

Calling pattern and properties of neuro-muscular property in black cicadae

黑蚱蝉（Ｃ．ａｔｒａｔａ Ｆａｂｒｉｃｉｕｓ）的复合脉冲型和单脉冲型叫声（ＣＰ－和 ＳＰ－叫声）分别具有呼叫声和求爱声特性。 ＣＰ－叫声的声脉冲由 ３个亚脉冲组成，而 ＳＰ－叫声为单一脉冲。两者都以约 ５０００ Ｈｚ的主频率为主音的单音调声，但 ＣＰ－叫声的主频率幅值比 ＳＰ－叫声平均高 １０．５ ｄＢ。两者发声运动的神经肌肉活动的波形结构虽相似，但 ＣＰ－叫声的发声运动由约５０ ｍｓ的起动过程逐步发展为平稳期，而 ＳＰ－叫声快速起动。 ＳＰ－叫声发声运动的神经肌肉活动增强而动作周期变慢，其动作电位的宽度、后电位和 ＥＭＧ的幅值分别比 ＣＰ－叫声平稳期内平均增高 ５２．８％、 ８８．８％和 ２６．３％；而声脉冲的潜伏期和重复周期分别平均减慢 ４９．５％和 ３８．５％。

The black cicadae(C.atrata Fabricius), the calls are of the complex-and single-pulse types (CP- and SP- call) possessing respectively properties of the calling and courtship song. In the CP-call each sound-pulse consists of three subpulses, while in the SP-call there is only one single pulse. Both are a monotone sound with the principal frequency at about 5000 Hz as the dominant tone, but the amplitudes of principal frequencies in the CP-call are 10.5 dB in average higher than those in the SP-call. Although the waveforms of neuro-musclar activeties of sounding movements are similar in two kinds of calls, the sounding movement of CP-call is characterized by gradual onset of about 50 ms developing into the steady period, while the start of the SP-call is quick. In the sounding movements of SP-call, the neuromusclar activeties are stronger with longer action periods, the duration of action potentials, amplitudes of after potentials and EMG are respectively 52.8%, 88.8% and 26.3% in average larger than those within the steady period of CP-call, while the latent priod and repetition period of spund-pulses are 49.5% and 38.5% in avearge slower.