喀斯特洞穴昆虫拉林裸灶螽尾须的超微结构

Ultrastructure of cerci of karst cave species Tachycines lalinus(Orthoptera:Rhaphidophoridae:Aemodogryllinae)

【目的】通过扫描电镜观察拉林裸灶螽(Tachycines lalinus)雌、雄成虫尾须的外部形态及感器种类、数量和分布特征,明确其尾须所具有的感器类型及分布规律,为进一步探讨拉林裸灶螽尾须感器生理功能及其因洞穴极端环境而产生的适应性变化奠定基础。【方法】以栖息于喀斯特洞穴的拉林裸灶螽雌、雄成虫为研究对象,利用扫描电子显微镜观察其尾须的整体形态以及尾须所具有的感器种类、数量及分布特征。【结果】拉林裸灶螽雌、雄成虫尾须均不分节,呈须状,着生方式特殊,几乎垂直于躯干。雌、雄成虫尾须具有相同的感器类型及相似的分布规律,尾须上的感器包括刺形感器、丝毛形感器、钟形感器、锥形感器和毛形感器5种类型,根据外部形态,刺形感器分为2种亚型(刺形感器1型和刺形感器2型)。其中,刺形感器1型、丝毛形感器、钟形感器、毛形感器分布最广,遍布于整个尾须的基部、中部、尾端部;刺形感器2型分布于尾须的基部和中部;锥形感器则仅分布于尾须基部。拉林裸灶螽雌虫尾须上的刺形感器1型、刺形感器2型和钟形感器数量均显著多于雄虫;雌、雄虫尾须上的丝毛形感器、锥形感器和毛形感器在数量上无显著差异。拉林裸灶螽雌成虫尾须上的刺形感器1型、刺形感器2型长度显著大于雄虫;雄成虫锥形感器、毛形感器长度显著大于雌成虫;雌、雄成虫丝毛形感器长度无显著差异。除雌成虫尾须上的刺形感器1型基部直径显著大于雄虫外,雌、雄成虫尾须上其他感器基部直径均无显著差异。【结论】拉林裸灶螽雌、雄成虫尾须上的感器类型相同,分布规律相似,但部分感器的数量、长度与基部直径存在一定差异。

【Objective】This study clarified external morphology as well as types,amounts and distribution features of sensilla on cerci of male and female Tachycines lalinus using scanning electron microscope to provide basis for studying physiological functions of sensilla and adaptive changes in ultrastructure of cerci in extreme cave environment.【Method】The external morphology and characteristics of sensilla on cerci of cave species T.lalinus were observed using scanning electron microscope.【Result】The cerci of T.lalinus were unsegmented,whisker-like,and relatively perpendicular to the body.The cerci of T.lalinus males and females had same sensilla types and similar sensilla distribution features.Five sensilla types were recorded on cerci,including sensilla chaetica,sensilla filiformia,sensilla campaniformia,sensilla basiconica and sensilla trichodea.Based on morphological characteristics,sensilla chaetica could be divided into two subtypes.Sensilla chaetica subtype 1,sensilla filiformia,sensilla campaniformia and sensilla trichodea widely distributed on basal,central and end parts of the cerci.Sensilla chaetica subtype 2 distributed on the basal and central parts of the cerci and sensilla basiconica distributed on basal part of cerci.The numbers of sensilla chaetica subtype 1,sensilla chaetica subtype 2 and sensilla campaniformia in females were significantly higher than those in males.No significant difference was found in numbers of sensilla filiformia,sensilla basiconica and sensilla trichodea between males and females.The lengths of sensilla chaetica subtype 1 and sensilla chaetica subtype 2 in females were significantly larger than those in males.The lengths of sensilla basiconica and sensilla trichodea in males were significantly larger than those in females.No significant difference was found in lengths of sensilla filiformia between males and females.No significant difference was found in base diameters of all sensilla between males and females except sensilla chaetica subtype 1.【Conclusion】The types and distribution of sensilla on cerci of T.lalinus adults of males and females were similar,but numbers,lengths and base diameters of some sensilla had differences between females and males.