Justus-Liebig-Universität Gießen, Institute for Animal Physiology, AG Integrative Sensory Physiology, Gießen, Germany.
CSIRO Manufacturing Business Unit, Clayton, Victoria, 3168, Australia.
Sci Rep. 2017 May 17;7(1):2031. doi: 10.1038/s41598-017-02132-1.
In orthopteran insects, a complex tibial organ has evolved to detect substrate vibrations and/or airborne sound. Species of New Zealand weta (Anostostomatidae) with tympanal ears on the foreleg tibia use this organ to communicate by sound, while in atympanate species (which communicate by substrate drumming) the organ is unstudied. We investigated the complex tibial organ of the atympanate ground weta, Hemiandrus pallitarsis, for vibration detection adaptations. This system contains four sensory components (subgenual organ, intermediate organ, crista acustica homolog, accessory organ) in all legs, together with up to 90 scolopidial sensilla. Microcomputed tomography shows that the subgenual organ spans the hemolymph channel, with attachments suggesting that hemolymph oscillations displace the organ in a hinged-plate fashion. Subgenual sensilla are likely excited by substrate oscillations transmitted within the leg. Instead of the usual suspension within the middle of the tibial cavity, we show that the intermediate organ and crista acustica homolog comprise a cellular mass broadly attached to the anterior tibial wall. They likely detect cuticular vibrations, and not airborne sound. This atympanate complex tibial organ shows elaborate structural changes suggesting detection of vibrational stimuli by parallel input pathways, thus correlating well with the burrowing lifestyle and communication by substrate-transmitted vibration.
在直翅目昆虫中，已经进化出一种复杂的胫骨器官来检测基质振动和/或空气传播的声音。具有前腿胫骨上鼓膜耳的新西兰蟋蟀（Anostostomatidae 科）物种利用该器官通过声音进行交流，而在无鼓膜的物种（通过基质击鼓进行交流）中，该器官尚未被研究。我们研究了无鼓膜的地面蟋蟀 Hemiandrus pallitarsis 的复杂胫骨器官，以寻找振动检测的适应特征。该系统在所有腿中包含四个感觉组件（亚关节器官、中间器官、声学嵴同源物、附属器官），以及多达 90 个栉状感器。微计算机断层扫描显示，亚关节器官跨越血腔通道，其附着处表明血淋巴振荡以铰接板的方式使器官移位。亚关节感器可能会被在腿部内传播的基质振荡激发。我们表明，中间器官和声学嵴同源物不是像通常那样悬挂在胫骨腔的中间，而是由广泛附着在前胫骨壁上的细胞团组成。它们可能会检测到表皮振动，而不是空气传播的声音。这种无鼓膜的复杂胫骨器官显示出精细的结构变化，表明通过并行输入途径检测振动刺激，这与挖掘生活方式和通过基质传播的振动进行交流很好地相关。
