Stress detection at the autotomy plane in the decapod crustacea
- 52 Downloads
The preformed autotomy plane of most reptantian decapods circumnavigates the basi-ischiopodite of the pereiopods. Associated with discrete areas of soft or thin cuticle in the proximity of the breakage plane are two connective chordotonal organs. These organs are sensitive to cuticular stress and are referred to as Cuticular Stress Detectors (CSD).
The CSD organs respond to pressure applied to the basi-ischiopodite and upon deformation of the discrete areas of soft cuticle onto which the connective tissue strands of the receptors insert. The CSDs exhibit a wide range of unit activity and both receptors have a similar population of unit types. Some units are active only on application or removal of a force applied to the soft cuticle but a large number of phaso-tonic and tonic units respond to a constant pressure applied to the soft cuticle. The majority of the units respond during application of the stimulus (ON units) but a small proportion of the units increase activity on removal of the stimulus (OFF units).
Passively produced tension in the anterior levator (autotomiser) muscle and depressor muscle tendons of the C-B joint is a potent stimulus to both receptors.
Both receptors respond to movement of the B-I joint of the Nephropsidean walking leg and to movement of the I-M joint in the pereiopods of other reptantian decapods where the basipodite and ischiopodite have fused. The degree of activity is not directly related to the joint position or direction of movement.
During autotomy both receptors respond strongly, particularly CSD 1. CSD 2 also shows increased activity but as the receptor is located distal to the breakage plane the receptor nerve is severed when breakage occurs.
After autotomy CSD 1 responds normally to deformation of the soft cuticle but manipulation of the breakage plane membrane or of the regenerating limb bud produces low levels of activity even though the stimulus is gross.
The possible functional roles of the receptors are discussed.
KeywordsJoint Position Unit Type Potent Stimulus Discrete Area Plane Membrane
Unable to display preview. Download preview PDF.
- Bullock, T. H., Horridge, G. A.: Structure and function in the nervous systems of invertebrates, vol. 2. San Francisco: W. H. Freeman and Co. 1965.Google Scholar
- Burke, W.: An organ for proprioception and vibration sense in Carcinus maenas. J. exp. Biol. 31, 127–137 (1954).Google Scholar
- Bush, B. M. H.: Proprioception by the coxo-basal chordotonal organ, CB, in the legs of the crab Carcinus maenas. J. exp. Biol. 42, 285–298 (1965a).Google Scholar
- —: Leg reflexes from chordotonal organs in the crab, Carcinus maenas. Comp. Biochem. Physiol. 15, 567–587 (1965b).Google Scholar
- —: Proprioeeption by chordotonal organs in the mero-carpopodite and carpopropodite joints of Carcinus maenas legs. Comp. Biochem. Physiol. 14, 185–199 (1965c).Google Scholar
- Carlisle, D. B.: On the hormonal inhibition of moulting in decapod crustacea. J. marine biol. Ass. 36, 291–307 (1957).Google Scholar
- Clarac, F.: Proprioception by the ischio-meropodite region in legs of the crab Carcinus mediterraneus C. Z. vergl. Physiol. 61, 224–245 (1968).Google Scholar
- —: Fonctions proprioceptives au niveau de la région basi-ischio-méropodite chez Astacus leptodactylus. Z. vergl. Physiol. 68, 1–24 (1970).Google Scholar
- —, Wales, W.: Contrôle sensoriel des muscles elevateurs au cours de la marche et de l'autotomie chez certains Crustacés Décapodes. C. R. Acad. Sci. (Paris). Ser. D 271, 2163–2166 (1970).Google Scholar
- Fredericq, L.: Nouvelles recherches sur l'autotomie chez le crabe. Arch. Biol. (Paris) 12, 169–197 (1891).Google Scholar
- Gomez, R.: Autotomy and regeneration in the crab Paratelphusa hydrodromous. J. Anim. Morph. Physiol. 11, 97–104 (1964).Google Scholar
- Horch, K. W., Salmon, M.: Production, perception and reception of acoustic stimuli by semiterrestrial crabs (Genus Ocypode and Uca, family Ocypodidae). forma et functio 1, 1–25 (1969).Google Scholar
- Howse, P.E.: The fine structure and functional organization of chordotonal organs. Symp. zool. Soc. Lond. 23, 167–198 (1968).Google Scholar
- McVean, A. R.: Neuromuscular co-ordination in Carcinus maenas. Ph. D. thesis, University of Wales, Cardiff, Wales (1970).Google Scholar
- Pringle, J. W. S.: Proprioception in insects. I. A new type of mechanical receptor from the palps of the cockroach. J. exp. Biol. 15, 101–113 (1938).Google Scholar
- —: The function of the lyriform organs of arachnids. J. exp. Biol. 32, 270–278 (1955).Google Scholar
- —: Proprioception in arthropods. In: The cell and the organism (ed. J. A. Ramsay and V. B. Wigglesworth). Cambridge: University Press 1961.Google Scholar
- Robinson, M. H., Abele, L. G., Robinson, B.: Attack autotomy: a defense against predators. Science 169, 300–301 (1970).Google Scholar
- Shelton, R. G. J., Laverack, M. S.: Observations on a redescribed crustacean cuticular sense organ. Comp. Biochem. Physiol. 25, 1049–1059 (1968).Google Scholar
- Taylor, R. C.: Functional properties of the chordotonal organ in the antennal flagellum of a hermit crab. Comp. Biochem. Physiol. 20, 719–729 (1967).Google Scholar
- Wales, W., Clarac, F., Dando, M. R., Laverack, M. S.: Innervation of the receptors present at the various joints of the pereiopods and third maxilliped of Homarus gammarus (L.) and other Macruran Decapods (Crustacea). Z. vergl. Physiol. 68, 345–384 (1970).Google Scholar
- —, Laverack, M. S.: Stress detection at the autotomy plane in the decapod crustacea. I. Comparative anatomy of the receptors of the basi-ischiopodite region. Z. vergl. Physiol. 73, 357–382 (1971).Google Scholar
- Whitear, M.: The fine structure of crustacean proprioceptors. I. The chordotonal organs in the legs of the shore crab. Carcinus maenas. Phil. Trans. B 245, 291–325 (1962).Google Scholar
- Wiersma, C. A. G.: Movement receptors in decapod crustacea. J. marine biol. Ass. 38, 143–152 (1959).Google Scholar
- Boettiger, E. G.: Unidirectional movement fibres from a proprioceptive organ of the crab, Carcinus maenas. J. exp. Biol. 36, 102–112 (1959).Google Scholar
- —, Bush, B M. H.: Functional neuronal connections between the thoracic and abdominal cords of the crayfish, Procambarus clarkii (Girard). J. comp. Neurol. 121, 207–235 (1963).Google Scholar
- Wood, F. D., Wood, H. E.: Autotomy in decapod crustacea. J. exp. Zool. 62, 1–49 (1932).Google Scholar
- Wyse, G. A., Maynard, D. M.: Joint receptors in the antennule of Panulirus argus. J. exp. Biol. 42, 521–535 (1965).Google Scholar