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 anterolateral 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 the 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 in 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 the 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.