Tegula (insect anatomy)
A tegula is a small sclerite situated above the base of the costal vein in the wings of various insects such as Orthoptera, Lepidoptera, Hymenoptera, Diptera, and Auchenorrhyncha, and attached to the antero-lateral portion of the mesonotum.[1] It is densely innervated, with sensory bristles, campaniform sensilla, as well as a chordotonal organ in some species.[2]
The tegula in locusts is a model system for studying the role of feedback from mechanoreceptors during movement.[3][4][5] In locusts, the tegula directly controls flight muscles. The motor neurons that control the activation of wing elevator muscles are phase-locked to the neurons that innervate the tegula such that when the tegula is electrically stimulated the elevator muscles initiate an upstroke.[5] When the tegula is removed, locust flight is clumsy and disordered at first but most animals adapt, suggesting the use of other mechanoreceptors to control flight.[6][7][8]
The tegula system is also a model for studying the role of neuromodulation for state-dependent motor control. Neural signals from the tegula only initiate wing muscle contraction when the animal is in flight (or fictive flight) due to endogenous release of the neuromodulator octopamine.[9] This mechanism ensures that the animal does not initiate a wing stroke if the bristles are deflected by wind as the animal is walking.
References
[edit]- ^ Fischer, Wolf and Büschges. "The locust tegula: kinematic parameters and activity pattern during the wing stroke". Journal of Experimental Biology. Retrieved 2010-08-31.
- ^ Fudalewicz-Niemczyk, Władysława (1963). L'innervation et les organes sensoriels des ailes des Diptères et comparaison avec l'innervation des ailes d'insectes d'autres ordres.
- ^ Ramirez, J.M.; Pearson, K.G. (1993). "Alteration of bursting properties in interneurons during locust flight". Journal of Neurophysiology. 70 (5): 2148–2160. doi:10.1152/jn.1993.70.5.2148. PMID 8294976.
- ^ Pearson, K.G.; Wolf, H. (1988). "Connections of hindwing tegulae with flight neurones in the locust, Locusta migratoria". Journal of Experimental Biology. 135 (1): 381–409. doi:10.1242/jeb.135.1.381. S2CID 83748273.
- ^ a b Wolf, H. (1993). "The Locust Tegula: Significance for flight rhythm generation, wing movement control and aerodynamic force production". Journal of Experimental Biology. 182 (1): 229–253. doi:10.1242/jeb.182.1.229. S2CID 86463750.
- ^ Gee, C.; Robertson, R. (1996). "Recovery of the flight system following ablation of the tegulae in immature adult locusts". Journal of Experimental Biology. 199 (6): 1395–1403. doi:10.1242/jeb.199.6.1395. PMID 9319291.
- ^ Kien, J.; Altman, J.S. (1979). "Connections of the locust wing tegulae with metathoracic flight motoneurons". Journal of Comparative Physiology. 133: 299–310. doi:10.1007/BF00661132. S2CID 11069678.
- ^ Büschges, A.; Pearson, K.G. (1991). "Adaptive modifications in the flight system of the locust after the removal of wing proprioceptors". Journal of Experimental Biology. 157 (1): 313–333. doi:10.1242/jeb.157.1.313. S2CID 26612516.
- ^ Ramirez, J.M.; Pearson, K.G. (1991). "Octopaminergic modulation of interneurons in the flight system of the locust". Journal of Neurophysiology. 66 (5): 1522–1537. doi:10.1152/jn.1991.66.5.1522. PMID 1765792.