Indirect and direct acoustic aggression in cicadas: first observations in the Palaearctic genus Tibicina Amyot (Hemiptera: Cicadomorpha: Cicadidae)

Tibicina Amyot is a cicada genus of the Palaearctic biogeographical region with seven taxa (species and subspecies) distributed in France. As in other cicadas, the sound production by tymbal vibration is restricted to males. In Tibicina, males are attracted by conspecific calling songs and tend to form groups of several individuals which maintain a minimal distance between each other. Observations based upon male–male interactions in such aggregations and on some preliminary experiments conducted with males kept in captivity revealed for the first time both indirect and direct aggression. Spacing and chorusing are interpreted as a by-product of indirect aggression mediated through the calling song. Direct aggression occurred when spacing is not respected. It is achieved through a ritualistic sequence that involves mainly the production of the rivalry song, an acoustic signal previously reported in the literature for two cicada species only. In addition, satellite males and male–male courting are reported. These preliminary results suggest that the sound social organization in the genus Tibicina is more elaborate than first suspected and should be reconsidered in terms of lek behaviour and sexual selection.     

A new species of the genus Megapomponia Boulard (Hemiptera: Cicadidae) from southern Vietnam,with a revised key to the species of Megapomponia

A new cicada species, Megapomponia macilenta Lee, sp. nov., is described from Thu Dau Mot, southern Vietnam. Information on geographic distributions of and a revised key to the species of the genus Megapomponia Boulard are provided.     

一种蝉鸣声数字化建模的改进方法

蝉鸣声是耳鸣掩蔽治疗最常用的一种匹配声源, 而目前数字化合成的蝉鸣声存在声音机械的问题. 针对该问题, 本文对蝉鸣合成数字化模型的激励源、声源模型和声道模型进行了优化: 使用滤波成型波作为激励源; 在声源信号中加入第二泛音分量; 对声道模型的参数进行修改. 最终合成的蝉鸣声在频谱丰富度和声音自然度得到了优化, 对耳鸣的掩蔽治疗提供了技术参考.     

Taxonomic separation by isozyme electrophoresis of two closely related species of Cicada L. (Hemiptera: Cicadoidea) in Portugal

Cicada orni (Linnaeus, 1758) and Cicada barbara (Stal, 1866), two closely related species of cicadas both present in Portugal, are very similar and often impossible to separate on the grounds of the morphology alone. Acoustic signals produced by males during pair formation and courtship are, however, different, which is evidence for the presence of two independent species. With a view to testing the usefulness of isozyme electrophoresis for distinguishing between this pair of species, specimens of both were collected in several locations either in sympatry or in allopatry, and then assayed for 19 enzyme loci. Starch gel electrophoresis gave evidence of genetic differentiation between the groups and strong support that they constitute two independent biological species. Moreover, three loci proved to be diagnostic for the separation between C. orni and C. barbara: aspartate aminotransferase (AAT-1), creatine kinase (CK-1) and malate dehydrogenase (MDH-1).