On spermatophore-producing aquatic microdrile oligochaetes (Annelida: Clitellata)

Zootaxa ◽  
2018 ◽  
Vol 4497 (1) ◽  
pp. 41
Author(s):  
PILAR RODRIGUEZ ◽  
STEVEN V. FEND

The formation of encapsulated spermatophores is exceptional among aquatic oligochaetes, although it seems to have occurred independently in several unrelated taxa. Among the microdriles, some variations appear unique to single species. The recently described lumbriculid Uktena riparia Fend et al. forms spermatophores in the male duct and attaches them within a deep spermathecal bursa. The attachment of spermatophores to the body wall, in the clitellar region, or in the vicinity of male or spermathecal pores has been reported in Paranadrilus Gavrilov, Bothrioneurum Štolc and some Aktedrilus Knöllner species. Anatomical comparison of reproductive organs suggests convergent development of glandular organs in the male duct or spermathecae, used for the formation, transfer and/or attachment of spermatophores to the concopulant worms. The presence of similar organs in Smithsonidrilus Brinkhurst, where spermatophores have not been reported, is also discussed. Furthermore, a lectotype is designated for Paranadrilus descolei Gavrilov, 1955. 

1994 ◽  
Vol 68 (4) ◽  
pp. 337-341 ◽  
Author(s):  
M.S. Omar ◽  
A.M.S. Raoof

AbstractThe activities of some key enzymes of the glycolytic and pentose phosphate pathways were investigated histochemically in adult female Onchocerca fasciata (Nematoda: Filarioidea). The distribution patterns of phosphofructokinase (PFK), aldolase (ALD), glyceraldehyde 3-phosphate dehydrogenase (G3PDH) and glucose 6-phosphate dehydrogenase (G6PDH) in different tissues of the worm were determined by employing NitroBlue Tetrazolium (NBT). The glycolytic enzymes PFK, ALD, and G3PDH were distributed throughout the hypodermal tissue, somatic muscles and reproductive organs. These enzyme activities were predominantly expressed in the hypodermal and reproductive tissues, both of which appeared to be metabolically more active than adjacent tissues. The high activities of the enzymes studied in the hypodermal tissue when compared with the minimal or low activity in the intestinal epithelium support the assumption that the worm's intestine, in contrast to the body wall, plays no significant role in the nutrient acquisition process. The results emphasize that both the glycolytic and hexose monophosphate pathways of carbohydrate metabolism are active components in energy production and biosynthetic processes in the various tissues of the worm. The functional significance of these glucose-metabolizing enzymes has been discussed with regard to their location in the tissues concerned.


1930 ◽  
Vol s2-73 (292) ◽  
pp. 651-666
Author(s):  
E. S. GOODRICH

In this paper a new species of Syllid, named Pionosyllis neapolitana, is described, whose chief characteristics are that it is hermaphrodite, and has reproductive organs of remarkably complex and constant structure.1 There are a pair of testes in each of the segments 10, 11, and 12, and a pair of ovaries in every segment from the thirteenth backwards throughout the region of the true intestine. A pair of nephridia with small nephridiostomes occurs in every segment from the fifth backwards, except in segments 11, 12, and 13, in which they become transformed into nephromixia functioning as sperm-ducts. Each sperm-duct is provided with a ciliated coelomostome opening into a male segment, and its postseptal tubule is enlarged into a sperm-sac where the spermatozoa form spermatophores. Presumably copulation takes place, since spermatophores are found lodged in paired spermathecae opening to the exterior on every female segment. One ovum at a time in every ovary enlarges and is extruded dorsally, apparently by breaking through the body-wall. The ova by this time are fertilized. They develop to an advanced stage surrounded by a cuticular membrane, and attached in pairs to every female segment. The young escape from the membrane when about eighteen segments have been formed. When the ova pass to the exterior they become attached to the laterodorsal surface of the female segments by means of fixing threads formed by special paired organs of fixation. These organs are derived from the spermathecae. Possibly successive generations of ova are extruded, but this has not yet been observed, nor is it known whether the fixing organs can again function as spermathecae. Exactly how and when fertilization takes place has not so far been determined.


Author(s):  
Dwi Darwati

Reproductive  health education should be given since early childhood by using language that is adapted to the stage of development. If you procrastinate and wait until the teenager it is already too late because in the days of the digital era, as now, all the information can be easily accessed by anyone including children early age. If the early childhood misinformed about their reproductive organs it would disrupt the physical and psychological development due to the wrong behavior in caring for and maintaining reproductive organs. Qur’an as the holy book of Muslims describes the steps of reproduction and  imparting education wisely as well as how to apply such education. This kind of education must be in accordance with the conditions of children and there should not be a lie about it We can also use media and methods such as pictures, songs, tap or other visual  media which can give clearer information, so that children can clearly see parts of the body, their characteristics, and how to treat and care them. The impropriate approach in conveying this kind of knowledge will be very dangerous for children. The provision of early age reproductive organs education can prevent the occurrence of deviant behavior as well as protect children from dangerous influence in early childhood development.


1997 ◽  
Vol 17 (4) ◽  
pp. 617-624 ◽  
Author(s):  
Philippe Moerman ◽  
Chris Van Geet ◽  
Hugo Devlieger
Keyword(s):  

Genetics ◽  
1994 ◽  
Vol 137 (2) ◽  
pp. 483-498
Author(s):  
J Ahnn ◽  
A Fire

Abstract We have used available chromosomal deficiencies to screen for genetic loci whose zygotic expression is required for formation of body-wall muscle cells during embryogenesis in Caenorhabditis elegans. To test for muscle cell differentiation we have assayed for both contractile function and the expression of muscle-specific structural proteins. Monoclonal antibodies directed against two myosin heavy chain isoforms, the products of the unc-54 and myo-3 genes, were used to detect body-wall muscle differentiation. We have screened 77 deficiencies, covering approximately 72% of the genome. Deficiency homozygotes in most cases stain with antibodies to the body-wall muscle myosins and in many cases muscle contractile function is observed. We have identified two regions showing distinct defects in myosin heavy chain gene expression. Embryos homozygous for deficiencies removing the left tip of chromosome V fail to accumulate the myo-3 and unc-54 products, but express antigens characteristic of hypodermal, pharyngeal and neural development. Embryos lacking a large region on chromosome III accumulate the unc-54 product but not the myo-3 product. We conclude that there exist only a small number of loci whose zygotic expression is uniquely required for adoption of a muscle cell fate.


1985 ◽  
Vol 260 (22) ◽  
pp. 12228-12233 ◽  
Author(s):  
H Takahashi ◽  
H Komano ◽  
N Kawaguchi ◽  
N Kitamura ◽  
S Nakanishi ◽  
...  

Genetics ◽  
2001 ◽  
Vol 157 (4) ◽  
pp. 1611-1622 ◽  
Author(s):  
Go Shioi ◽  
Michinari Shoji ◽  
Masashi Nakamura ◽  
Takeshi Ishihara ◽  
Isao Katsura ◽  
...  

Abstract Using a pan-neuronal GFP marker, a morphological screen was performed to detect Caenorhabditis elegans larval lethal mutants with severely disorganized major nerve cords. We recovered and characterized 21 mutants that displayed displacement or detachment of the ventral nerve cord from the body wall (Ven: ventral cord abnormal). Six mutations defined three novel genetic loci: ven-1, ven-2, and ven-3. Fifteen mutations proved to be alleles of previously identified muscle attachment/positioning genes, mup-4, mua-1, mua-5, and mua-6. All the mutants also displayed muscle attachment/positioning defects characteristic of mua/mup mutants. The pan-neuronal GFP marker also revealed that mutants of other mua/mup loci, such as mup-1, mup-2, and mua-2, exhibited the Ven defect. The hypodermis, the excretory canal, and the gonad were morphologically abnormal in some of the mutants. The pleiotropic nature of the defects indicates that ven and mua/mup genes are required generally for the maintenance of attachment of tissues to the body wall in C. elegans.


Parasitology ◽  
1965 ◽  
Vol 55 (1) ◽  
pp. 173-181 ◽  
Author(s):  
D. L. Lee

The cuticle of adults ofNippostrongylus brasiliensishas been described using histological, histochemical and ultrastructural techniques.The cuticle has the following layers: an outer triple-layered membrane; a single cortical layer; a fluid-filled layer which is traversed by numerous collagen fibrils; struts which support the fourteen longitudinal ridges of the cuticle and which are suspended by collagen fibrils in the fluid-filled layer; two fibre layers, each layer apparently containing three layers of fibres; and a basement lamella.The fluid-filled layer contains haemoglobin and esterase.The muscles of the body wall are attached to either the basement lamella or to the fibre layers of the cuticle.The mitochondria of the hypodermis are of normal appearance.The longitudinal ridges of the cuticle appear to abrade the microvilli of the intestinal cells of the host.Possible functions of the cuticle are discussed.I wish to thank Dr P. Tate, in whose department this work was done, for helpful suggestions and criticism at all stages of this work, and Mr A. Page for technical assistance. I also wish to thank Professor Boyd for permission to use the electron microscope in the Department of Anatomy.


1997 ◽  
Vol 17 (4) ◽  
pp. 617-624 ◽  
Author(s):  
Philippe Moerman ◽  
Chris Van Geet ◽  
Hugo Devlieger
Keyword(s):  

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