蚊蝎蛉捕捉足构造

Structure of raptorial legs in Bittacus (Mecoptera:Bittacidae)

依据光学显微镜和扫描电镜观察,对扁蚊蝎蛉Bittacus planus Cheng和缠绕蚊蝎蛉Bittacus implicatus Huanget Hua成虫足的外部形态、肌肉组织及超微结构进行了描述和绘图。蚊蝎蛉成虫三对足结构相似,均为捕捉式,以高度特化的跗节捕捉猎物,各跗分节间具发达的关节、凹槽和爪缩肌肌腱膨大区,第4和5跗分节的齿形成嵌合构造,在昆虫纲中为该类群独有特征。首次发现胫节伸肌b由腿节基部发出的一小块三角形肌肉组织和一条长肌腱组成;爪缩肌肌腱在第5跗分节凹槽末端有一突起,收缩时突起羁绊于凹槽内的"Y"字形底托。分析了成虫捕食行为与捕捉足构造之间的关系,并简要比较了蚊蝎蛉捕捉足与螳螂捕捉足的结构特点。

The morphology, musculature, and ultrastructure of legs of Bittacus planus Cheng and B. implicatus Huang et Hua adults were described and illustrated based on observations with optical microscopy and scanning electron microscopy. Adult hangingflies have three pairs of legs with similar structure, all being raptorial with grasping structure formed from the fourth and fifth tarsomeres, unique in Insecta. It has been found for the first time that the femoro-tibial extensor b is composed of an elongate thin tendon arising proximally from a small triangular femoral muscle. The tendon of pretarsal flexor is modified into a strong flexor muscle in a shuttle-shaped swollen area, bearing distally a process which is blocked by a Y-shaped pedestal in a notch. The relationships between the predating habits of adults and the structure of raptorial legs were analyzed, and the characteristics of the raptorial legs of hangingflies and mantids are tentatively compared.