THELANDROS MAGNAVULVARIS (RANKIN, 1937) SCHAD, 1960 (NEMATODA: OXYUROIDEA) FROM THE GREEN SALAMANDER, ANEIDES AENEUS

1963 ◽  
Vol 41 (6) ◽  
pp. 943-946 ◽  
Author(s):  
G. A. Schad

Thelandros magnavulvaris, previously known only from females, is redescribed from both male and female specimens. It is distinguished from T. salamandrae, the species it most resembles, in that the vulva is pedunculate in the former but flush with the body wall in the latter. The males differ in spicule length, the spicule measuring 35–39 μ in T. salamandrae and 40–58 μ in T. magnavulvaris. As parasitic helminths have not been previously reported from Aneides aeneus, the records of T. magnavulvaris and Baerietta diana from this host are new.

1962 ◽  
Vol 40 (3) ◽  
pp. 465-510 ◽  
Author(s):  
R. D. S. Bhatnagar ◽  
J. G. Rempel

A comparison of the structure of the male and female pedipalpi shows that the patella, tibia, tarsus, and the pretarsus of the male are modified. The tarsus in the male is represented by a spoon-shaped cymbium, and the pretarsus by a complex, copulatory palpal organ. This organ in the mature male is a "more specialized" type with an internal receptaculum seminis guarded by the subtegulum, tegulum, median apophysis, radix, terminal apophysis, conductor, and the embolus. The walls of the fundus and the reservoir are of uniform thickness, containing numerous pores on the side facing the gland cells. The ectodistal tooth of the cymbium fits into the socket of the median apophysis, the embolic tip rests on the conductor, and the embolic base is hooked to the basal tooth of the radix. A trigger-like mechanism of extension of the palpal organ is described.The palpal organ arises from the hypodermal cells of the claw fundament. A longitudinal invagination in the ventral lobe of the fundament forms the receptaculum seminis and the dorsal lobes form the accessory sclerites. After transformation of its fundament, the new claw loses connection with the muscle tendons and is short and simple. There is no correlation between the teeth of the claw and the sclerites of the organ.The female copulatory organs consist of paired, dumb-bell-shaped spermathecae; coiled sac-like bursae copulatrices; small, straight fertilization tubes; and blind canals. Ventrally the apparatus is covered by a heavily sclerotized epigynum with an elliptical opening into the atrium which contains the outer openings of the bursae copulatrices. The embolus penetrates the bursa to bring its tip partly within the spermatheca where the broken embolic fragment is later found.The female apparatus arises as a pair of double invaginations of the body wall within the epigastric furrow, immediately ventrad of the opening of the uterus. In successive stages, gradual development of the tissue brings the invaginations outside the epigastric furrow. The two pockets of the invaginations increase in size, the dorsal ones developing into the spermathecae and the ventral ones into the bursae copulatrices.


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 ◽  
...  

2021 ◽  
Vol 9 (8) ◽  
pp. 848
Author(s):  
Elise E. B. LaDouceur ◽  
Linda A. Kuhnz ◽  
Christina Biggs ◽  
Alicia Bitondo ◽  
Megan Olhasso ◽  
...  

Sea pigs (Scotoplanes spp.) are deep-sea dwelling sea cucumbers of the phylum Echinodermata, class Holothuroidea, and order Elasipodida. Few reports are available on the microscopic anatomy of these deep-sea animals. This study describes the histologic findings of two, wild, male and female Scotoplanes sp. collected from Monterey Bay, California. Microscopic findings were similar to other holothuroids, with a few notable exceptions. Sea pigs were bilaterally symmetrical with six pairs of greatly enlarged tube feet arising from the lateral body wall and oriented ventrally for walking. Neither a rete mirabile nor respiratory tree was identified, and the large tube feet may function in respiration. Dorsal papillae protrude from the bivium and are histologically similar to tube feet with a large, muscular water vascular canal in the center. There were 10 buccal tentacles, the epidermis of which was highly folded. Only a single gonad was present in each animal; both male and female had histologic evidence of active gametogenesis. In the male, a presumed protozoal cyst was identified in the aboral intestinal mucosa, and was histologically similar to previous reports of coccidians. This work provides control histology for future investigations of sea pigs and related animals using bright field microscopy.


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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