The fine structure of the germinal mass, brood cavity and birth canal of the rediae of the monoxenous hemiuroid digenean Bunocotyle progenetica Chabaud & Buttner, 1959

2019 ◽  
Vol 94 ◽  
Author(s):  
I.M. Podvyaznaya ◽  
A.A. Petrov ◽  
K.V. Galaktionov
Keyword(s):  
Fine Structure ◽  
Life Cycle ◽  
Body Wall ◽  
The Body ◽  
Cellular Composition ◽  
Birth Canal ◽  
Offspring Number ◽  
Transmission Electron ◽  
Reproductive Apparatus ◽  
Germinal Mass

Abstract Bunocotyle progenetica is a hemiuroid digenean whose sexual adults become fully developed and lay their eggs inside the rediae in the molluscan host. In this study, the fine structure of the germinal mass, brood cavity and birth canal in the B. progenetica rediae was examined using transmission electron and confocal microscopy. The large germinal mass attached to the body wall has a cellular composition typical for this organ. The characteristic traits of this germinal mass are weakly developed supporting tissue and the presence of deep lacunae opening into the brood cavity. These lacunae presumably participate in feeding the deeply lying embryos and facilitate their release into the brood cavity. The germinal mass is also characterized by intensive degeneration of cellular elements, which may represent a mechanism controlling the offspring number, limited in this species by the size of the redial brood cavity. The brood-cavity lining consists of flattened cells bearing lamellar projections and is connected anteriorly with the epithelium of the birth canal. The brood-cavity musculature, which is well developed in other hemiuroid digeneans, is significantly reduced in B. progenetica, most likely because their cystophorous cercariae remain inside the rediae, removing the need for muscle contractions pushing them through the brood cavity. The birth canal comprises three regions distinguished by the structure of the lining and muscle arrangement. The comparison of rediae of B. progenetica with parthenitae of other digeneans has shown that the organization of the redial reproductive apparatus in this species may have been influenced by life-cycle modification.

The fine structure of the body wall of Polymorphus minutus (Goeze, 1782) (Acanthocephala)

Parasitology ◽  
1965 ◽  
Vol 55 (2) ◽  
pp. 357-364 ◽  
Author(s):  
D. W. T. Crompton ◽  
D. L. Lee
Keyword(s):  
Fine Structure ◽  
Electron Microscope ◽  
Light Microscope ◽  
Body Wall ◽  
Technical Assistance ◽  
The Body ◽  
Parasitic Nematodes ◽  
Surface Layers ◽  
Longitudinal Muscles

The body wall of Polymorphus minutus has been studied with the electron microscope and the structure of the various layers has been described.The layers are the same in number as those seen with the light microscope, and pores have been found which penetrate the cuticle. Thus, the structure of the surface layers is such as would facilitate the absorption of nutrients.It has been found that the cuticle and striped layer extend over the trunk spines, a feature which increases the area of the absorptive surface of the parasite.The structure of the striped layer of the praesoma supports the theory that the praesoma body wall and lemnisci are involved in the absorption of fat.Mitochondria have been detected in the felt and radial layers of the body wall and in the circular and longitudinal muscles.The body wall of this acanthocephalan worm is entirely different from the body wall of trematodes, cestodes and parasitic nematodes.We are grateful to Dr P. Tate for helpful discussions, Dr R. J. Skaer for criticism of the manuscript and to Professor J. D. Boyd for permission to use the electron microscope in the Department of Anatomy. Thanks are also due to Mr A. J. Page for technical assistance.

Ultrastructural morphology of the body wall, stoma, and stomatostyle of the nematode, Tylenchorhynchus dubius (Bütschli, 1873) Filipjev, 1936

1972 ◽  
Vol 50 (4) ◽  
pp. 457-465 ◽  
Author(s):  
J. R. Byers ◽  
R. V. Anderson
Keyword(s):  
Fine Structure ◽  
Body Wall ◽  
Parasitic Nematode ◽  
Structure And Function ◽  
The Body ◽  
Parasitic Nematodes ◽  
Plant Parasitic Nematodes ◽  
Ultrastructural Morphology ◽  
And Function ◽  
Plant Parasitic

The fine structure of the body wall, stoma, and stomatostyle of the plant parasitic nematode, Tylenchorhynchus dubius, is described. The body wall consists of a six-layered cuticle, about 1 μ thick, and a thin interchordal hypodermis. Some details of the labial framework and the cuticular lining of the stoma are described. The shaft of the stomatostyle is composed of five distinct layers. The attachment between the shaft and the stomatal cuticle is characterized by several specializations. One of these is an extensive attachment complex formed at the lateral junction between the stomatal and stylet epithelia. The protractor musculature consists of three main units which are each subdivided anteriorly into smaller elements. Also present are four secondary muscle elements which extend posteriorly beyond the base of the stylet and attach to the cuticular lining of the esophagus above the dorsal duct orifice.The ultrastructural morphology described for T. dubius is compared with that known for other plant parasitic nematodes. Some likely relationships between structure and function are also discussed.

Fine Structure of the Body Wall and Vulva Area of Pratylenchus Penetrans

Nematologica ◽  
1972 ◽  
Vol 18 (2) ◽  
pp. 234-238 ◽  
Author(s):  
M. Kisiel ◽  
S. Himmelhoch ◽  
B.M. Zuckerman
Keyword(s):  
Fine Structure ◽  
Body Wall ◽  
The Body ◽  
Pratylenchus Penetrans

Fine structure of the body wall cuticle of females of Bellodera utahensis and Ekphymatodera thomasoni (Sarisoderini, Heteroderinae)

1992 ◽  
Vol 70 (2) ◽  
pp. 268-273 ◽  
Author(s):  
J. G. Baldwin ◽  
C. D. Eddleman
Keyword(s):  
Fine Structure ◽  
Female Body ◽  
Body Wall ◽  
The Body ◽  
Intermediate Zone ◽  
Crystalline Layer ◽  
Young Females ◽  
Surface Patterns ◽  
Phylogenetic Character

The female body wall cuticle of Bellodera utahensis and Ekphymatodera thomasoni (Heteroderinae) has an external sub-crystalline layer and four concentric layers, A, B, C, and D. Surface striae of the cuticle of B. utahensis are transverse, whereas those of E. thomasoni are longitudinal. The surface patterns are reflected in the A layer, which is thickest in the elevated regions between striae. The B layer consists of vertical columns and is continuous in young females but is broken into discontinuous patches as the female increases in girth. The C layer and adjacent D layer tend to merge at an intermediate zone in B. utahensis and E. thomasoni. The D layer is composed of fibrils about 31 nm in diameter arranged in a helicoidal pattern. An E layer adjacent to the hypodermis is present only in B. utahensis. The D layer is not resolved in newly molted females of B. utahensis, contrary to E. thomasoni. The presence of a D layer is a phylogenetic character shared with most other Sarisoderini. Although further investigation of Rhizonema and Hylonema is needed, existing knowledge of the body wall cuticle in females strengthens hypotheses of the monophyly of Sarisoderini.

The fine structure of the trunk and praesoma wall of Acanthocephalus ranae (Schrank, 1788), Lühe, 1911

Parasitology ◽  
1967 ◽  
Vol 57 (3) ◽  
pp. 475-486 ◽  
Author(s):  
R. A. Hammond
Keyword(s):  
Electron Microscopy ◽  
Fine Structure ◽  
Electron Microscope ◽  
Light Microscope ◽  
Body Wall ◽  
Technical Assistance ◽  
The Body ◽  
The Other ◽  
Fat Excretion ◽  
Research Grant

The wall of the trunk, that of the praesoma, and the lemnisci of Acanthocephalus ranae have been studied by electron microscopy. Striations visible in sections of the body wall under the light microscope do not correspond with the ‘striped layer’ revealed by the electron microscope.A new region, the ‘canal layer’, has been described. This contains canals running into the body wall from cuticular pores.Structurally the wall of the trunk and that of the praesoma are similar. The lemnisci resemble the ‘inner layer’ of the praesoma wall. However, it is suggested that the wall of the trunk differs physiologically from that of the praesoma, and from the lemnisci. The possible roles of the wall of the praesoma and the lemnisci in fat excretion or uptake have been discussed.The body wall of A. ranae has been compared with that of the other acantho-cephalans studied with the electron microscope.Grateful acknowledgement is made to D.S.I.R. (now S.R.C.) for a research grant to the Department of Zoology for the purchase of a Huxley ultramicrotome, a vacuum coating unit, and an AEI EM 6 electron microscope.I am grateful to Dr D. A. Erasmus for reading and criticizing the manuscript, and to Mr T. Davies for valuable technical assistance.

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