Data from: Tracheal compression in pupae of the beetle Zophobas morio

Insects that are small or exhibit low metabolic rates are considered to not require active ventilation to augment diffusive gas exchange. Some pupae with low metabolic rates exhibit abdominal pumping, a behaviour that is known to drive tracheal ventilation in the adults of many species. However, previous work on pupae suggests that abdominal pumping may serve a non-respiratory role. To study the role of abdominal pumping in pupa of the beetle Zophobas morio, we visualized tracheal dynamics with X-rays while simultaneously measuring haemolymph pressure, abdominal movement, and CO2 emission. Pupae exhibited frequent tracheal compressions that were coincident with both abdominal pumping and pulsation of pressure in the haemolymph. However, more than 63% of abdominal pumping events occurred without any tracheal collapse and hence ventilation, suggesting that the major function of the abdominal pump is not respiratory. In addition, this study shows that the kinematics of abdominal pumping can be used to infer the status of the spiracles and internal behaviour of the tracheal system.

体型微小或代谢率较低的昆虫，通常被认为无需借助主动通气来增强扩散性气体交换。部分代谢率较低的蛹类会表现出腹部泵动行为，该行为在多数物种的成虫中已被证实可驱动气管通气。然而，过往针对蛹类的研究表明，腹部泵动或许承担着非呼吸相关的功能。为探究Zophobas morio甲虫蛹的腹部泵动功能，我们利用X射线对气管动态进行可视化观测，并同步监测血淋巴压力、腹部运动与二氧化碳排放情况。蛹类常出现气管压缩现象，该现象与腹部泵动及血淋巴压力脉动均同步发生。然而，超过63%的腹部泵动事件并未伴随气管塌陷，因此未产生通气效应，这表明腹部泵动的核心功能并非呼吸相关。此外，本研究证实，腹部泵动的运动学特征可用于推断气门状态与气管系统的内部活动规律。