The complex tibial organ of the New Zealand ground weta: sensory adaptations for vibrational signal detection

Abstract 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 s...

Description complète

Enregistré dans:
Détails bibliographiques
Auteurs principaux: Johannes Strauß, Kathryn Lomas, Laurence H. Field
Format: article
Langue:EN
Publié: Nature Portfolio 2017
Sujets:
R
Q
Accès en ligne:https://doaj.org/article/4c1905fab8ff48fb9ea72475e79a4fa6
Tags: Ajouter un tag
Pas de tags, Soyez le premier à ajouter un tag!
Description
Résumé:Abstract 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.