Skip to main content Accessibility help

The excretory system of nematodes: structure and ultrastructure of the excretory system of Panagrellus redivivus, Ditylenchus myceliophagus with some observations on D. dipsaci and Heterodera rostochiensis

  • H. K. Narang (a1)


The structure and ultrastructure of the excretory system of Panagrellus redivivus, Ditylenchus myceliophagus, D. dipsaci and the second-stage larvae of the Heterodera rostochiensis are described. Panagrellus has two lateral ducts, a median duct and a gland. The two lateral ducts are joined over the anterior part of the oesophageal bulb to form a loop. Anteriorly this loop continues as a median duct, which opens to the exterior in an excretory pit, part of the system lies free in the pseudocoelom. The lumen of the lateral excretory duct and the greater part of the median duct is surrounded by capitate tubules, which open into the lumen of the excretory duct. Capitate tubules develop by the invagination of the hypodermal membranes and lie embedded in thick cytoplasm surrounded by mitochondria. Ensheathed in cell membranes the excretory duct forms an anastomosis in the loop and at three other places along the length of each lateral excretory duct. At these regions there are nerve endings. The excretory gland opens posteriorly into the loop and is full of Golgi complexes, endoplasmic reticulum and secretory granules.

In the system of Ditylenchus and the second-stage larva of Heterodera the right lateral duct is absent while the left lateral excretory duct continues anteriorly past the median excretory duct; a true loop is not formed. The median excretory duct lies embedded almost throughout its length in the excretory gland. Capitate tubules are present along the length of the lateral excretory duct, but, unlike Panagrellus, are not present around the median excretory duct. Anastomosis is not formed in the excretory ducts. In other respects the system of the species studied is similar to that of Panagrellus.

The capitate tubules form a system of fine microtubules. Their ultrastructure and, particularly, their association with large numbers of mitochondria, is very reminiscent of structures thought to be concerned with an active transport role, related to ionic and osmoregulation in other phyla.

The excretory system is almost certainly hypodermal in origin. Differences between the morphology and relations of the median duct of Enoplus (Narang, 1970), on the one hand, and that of the other forms studied suggest that these ducts may have different origins: the presence of separate nuclei in the lateral duct and gland portions of the system would be consistent with this view. It is considered that the two parts may have originated separately and have become joined during evolution. It is also shown that the excretory system of Ditylenchus cannot be derived either from an H-shaped system or from a primitive gland system.

I wish to thank Professor C. Ellenby and Mr L. Smith for their helpful criticism.



Hide All
Alicata, J. E. (1935). Early developmental stages of nematodes occurring in swine. U.S. Department of Agricultural Technical Bulletins, no. 489, pp. 196.
Allen, M. W. (1960). Alimentary canal, excretory and nervous systems. In Nematology (ed. Sasser, J. N. and Jenkins, W. R.), pp. 136–9. Chapel Hill: The University of North Carolina Press.
Beam, H. W. & Anderson, E. (1956). Ultrastructure of Golgi apparatus, mitochondria and endoplasmic reticulum. Proceedings of Iowa Academy of Science 63, 686–92.
Chitwood, M. B. & Chitwood, B. G. (1950). An Introduction to Nematology, section I, chap. II and IX. Babylon Press, Babylon, New York.
Cobb, N. A. (1890). Oxyuris-larvae hatched in the human stomach under normal conditions. Proceedings of Linnean Society of New South Wales 5, 168–85.
Dalton, A. J. (1951). Structural detail of some of the epithelial cell types in kidney of the mouse as revealed by the electron microscope. Journal of National Cancer Institute 11, 1163–85.
Davey, K. G. & Kan, S. P. (1968). Moulting in parasitic nematode Phocanema decipiens. IV. Ecdysis and its control. Canadian Journal of Zoology 46, 893–9.
Evans, A. A. F. & Fisher, J. M. (1970). The excretory system of three Ditylenchus spp. Journal of Nematology 2, 260–4.
Fawcett, D. W. (1966). The Cell: Its Organelles and Inclusions. Philadelphia and London: W. B. Saunders Co.
Golovin, E. P. (1902). Observations on Nematodes. II. Excretory apparatus. [Russian text.] Uchenye/Zapiski Imperatorskago Kazanskago Universiteta, pp. 1120.
Goodey, T. (1951). Soil and Freshwater Nematodes. London: Methuen and Co. Ltd.
Lee, D. L. (1970). The fine structure of the excretory system in adult Nippostrongylus brasiliensis (Nematoda) and a suggested function for the excretory gland. Tissue and Cell 2, 225–31.
Mueller, J. F. (1927). The excretory system of Anisakis simplex. Zeitschrift für Zellforschung und mikroscopische Anatomie 5, 495504.
Narang, H. K. (1970). The excretory system of nematodes: Structure and ultrastructure of the excretory system of Enoplus brevis (Bastian). Nematologica 16, 517–22.
Pantin, C. F. A. (1962). Notes on Microscopical Techniques for Zoologists. Cambridge University Press.
Pease, D. C. & Baker, R. F. (1950). Electron microscopy of the kidney. American Journal of Anatomy 87, 349–90.
Rhodin, J. (1958). Anatomy of kidney tubules. International Review of Cytology 7, 485534.
Roggen, D. R., Raski, D. J. & Jones, N. O. (1966). Cilia in nematode sensory organs. Science 152, 515–16.
Sjostrand, F. S. & Rhodin, J. (1953). The ultrastructure of the provisional convoluted tubules of the mouse kidney as revealed by high resolution electron microscopy. Experimental Cell Research 4, 436–56.
Smith, L. (1965). The excretory system of Panagrellus redivivus (T. Goodey, 1945). Comparative Biochemistry and Physiology 15, 8992.
Steiner, G. (1919). Untersuchungen über den allgemeinen Bauplan de Nematodenkörpers, pp. 196.
Steiner, G. (1920). Betrachtungen zur Frage des Verwandschaftsverhaltnisses der Rotatorien und Nematoden. Festschrift Zshokke, pp. 116.
Stewart, F. H. (1916). On the life history of Ascaris lumbricoides. British Medical Journal 2, 57.
Waddell, A. H. (1968). The excretory system of the kidney worm Stephanurus dentatus (Nematoda). Parasitology 58, 907–19.
Wigglesworth, V. B. & Salpeter, M. M. (1962). Histology of the malpighian tubules in Rhodium prolixus Stal (Hemiptera). Journal of Insect Physiology 8, 299307.
Yuen, P. H. (1968). Electron microscopical studies on the anterior end of Panagrellus silusiae (Rhabditidae). Nematologica 14, 554–64.


Full text views

Total number of HTML views: 0
Total number of PDF views: 0 *
Loading metrics...

Abstract views

Total abstract views: 0 *
Loading metrics...

* Views captured on Cambridge Core between <date>. This data will be updated every 24 hours.

Usage data cannot currently be displayed