# Influence of Variation in Hind Leg Structure of Auchenorrhyncha on Their Jumping Performance

## TL;DR

This study shows how differences in hind leg structures of Auchenorrhyncha insects affect their jumping performance, including height, distance, and stability.

## Contribution

The study provides new experimental evidence on how structural adaptations in hind legs influence jumping performance in Auchenorrhyncha insects.

## Key findings

- Structural differences in hind legs significantly affect jumping performance metrics like height and distance.
- Leafhoppers achieve quicker and more stable take-offs due to unique hind leg structures.
- Microtrichia density and gear-like structures correlate with jumping efficiency and energy storage.

## Abstract

Although small insects generally have similar jumping mechanisms, their jumping performances exhibit significant variations. By conducting a comparative analysis of the external morphology of the hind legs using scanning electron microscopy (SEM) and recording jumping motions using high-speed capture technology, this study quantitatively evaluated the physical parameters generated during the jumping process. The results indicate that differences in the morphological structure of the hind legs significantly affect jumping performance, specifically manifested as notable divergence in key metrics, such as jumping height, distance, and initial velocity among different species. This finding provides important experimental evidence for the further understanding of the biomechanical mechanisms of insect jumping behavior.

Four species representing four different families of the hemipteran insect suborder Auchenorrhyncha, Lepyronia coleoptrata (Aphrophoridae), Euricania ocellus (Ricaniidae), Kolla sp. (Cicadellidae) and Tricentrus sp. (Membracidae) were investigated using high-speed photography and scanning electron microscopy to identify hind leg structures that may influence jumping performance. The coxa–trochanteral joint, femur and tibia were found to have distinct structural adaptations that vary among these jumping insects. Froghoppers and planthoppers possess a coxal protrusion which is absent in leafhoppers and treehoppers, the latter featuring a more recessed coxal fossa. The medial coxae of these insects exhibit fields of microtrichia that vary in density and fine structure. Medial gears on the trochanters of Tricentrus sp. are implicated in the storage of energy prior to their jumps. These structural differences manifest in the insects’ jumping performance. The study demonstrated a correlation between the robustness of the microtrichia field interaction and the insect’s jumping capability. Specifically, leafhoppers, equipped with a pair of rivet-like structures connecting the hind coxae, were observed to achieve quicker and more stable take-offs. The study reveals that structural variations in the hind legs of Auchenorrhyncha species significantly influence their jumping performance, with implications for both efficiency and stability.