Proboscises of many fluid-feeding insects share a common architecture: they have a partially open food canal along their length. This feature has never been discussed in relation to the feeding mechanism. We formulated and solved a fluid mechanics model of fluid uptake and estimated the time required to completely fill the food canal of the entire proboscis through the openings along its length. Butterflies and moths are taken as illustrative and representative of fluid-feeding insects. We demonstrated that the proposed mechanism of filling the proboscis with fluid through permeable lengthwise bands, in association with a thin film of saliva in the food canal, offers a competitive pathway for fluid uptake. Compared with the conventional mechanism of fluid uptake through apically restricted openings, the new mechanism provides a faster rate of fluid uptake, especially for long-tongued insects. Accordingly, long-tongued insects with permeable lengthwise bands would be able to more rapidly exploit a broader range of liquids in the form of films, pools, and discontinuous columns, thereby conserving energy and minimizing exposure to predators, particularly for hovering insects.

许多以食水为食的昆虫的象鼻有一个共同的结构：它们在其长度上具有部分开放的食道。从未针对送纸机构讨论过此功能。我们制定并解决了流体吸收的流体力学模型，并估计了通过整个长管的开口完全充满整个长鼻的食道所需的时间。蝴蝶和飞蛾被用作说明和代表以液体为食的昆虫。我们证明了所提出的通过可渗透的纵向条带向长鼻充液的机制，与食道中唾液的薄膜相结合，为液体的吸收提供了竞争途径。与传统的通过顶端受限的开口吸收液体的机制相比，新的机制可以更快地吸收液体，特别是对于长舌虫。因此，具有可渗透的纵向带的长舌昆虫将能够以薄膜，水池和不连续柱的形式更迅速地利用更大范围的液体，从而节省能量并最大程度地减少对捕食者的暴露，特别是对于盘旋昆虫而言。