Department of Zoology, University of Oxford, Oxford OX1 3PS, UK.
Department of Zoology, University of Oxford, Oxford OX1 3PS, UK.
Arthropod Struct Dev. 2020 Mar;55:100918. doi: 10.1016/j.asd.2020.100918. Epub 2020 Feb 27.
Cicadas and many of their relatives (Hemiptera: Cicadomorpha) generate vibroacoustic signals using tymbal organs located on their first two abdominal segments. Although tymbals are well-studied in Cicadidae, their systematic distribution in other Cicadomorpha and their possible homologies to the vibroacoustic mechanisms of other Hemiptera have been debated for more than a century. In the present study, we re-examine the morphology of the musculoskeletal system of cicadomorphan vibroacoustic organs, and we document their systematic distribution in 78 species drawn from across the phylogeny of Cicadomorpha. We also compare their morphology to the recently-described snapping organ of planthoppers (Fulgoromorpha). Based on the structure and innervation of the metathoracic and abdominal musculoskeletal system, we find that several key elements of cicadomorphan vibroacoustic organs that have previously been assigned to the first abdominal segment in fact belong to the second. We find that tymbal organs are nearly ubiquitous in Cicadomorpha, and conclude based on their phylogenetic distribution, that they are likely to be synapomorphic. The unusual tymbal-like organs of the Deltocephalinae and Typhlocybinae, represent derived modifications. Finally, we propose a standardised terminology for sternal components of the cicadomorphan vibrational organs, which can be used in future taxonomic descriptions.
蝉和它们的许多近亲（半翅目：蝉科）使用位于前两个腹节上的鼓膜器官产生声振信号。尽管蝉科的鼓膜已被广泛研究，但它们在其他蝉科中的系统分布以及与其他半翅目昆虫的声振机制的可能同源性已经争论了一个多世纪。在本研究中，我们重新检查了蝉科鸣虫器官的肌肉骨骼系统的形态，并记录了它们在蝉科系统发育范围内的 78 种物种中的系统分布。我们还将其形态与最近描述的叶蝉的弹拨器官（同翅目：叶蝉科）进行了比较。基于胸和腹肌肉骨骼系统的结构和神经支配，我们发现以前被认为属于第一腹节的几个蝉科鸣虫器官的关键要素实际上属于第二腹节。我们发现鼓膜器官在蝉科中几乎无处不在，并根据其系统发育分布得出结论，它们可能是同源的。德尔塔蝉科和叶蝉科不寻常的鼓膜状器官是衍生的变体。最后，我们为蝉科鸣虫器官的胸骨成分提出了一个标准化的术语，可用于未来的分类描述。
