Sexually dimorphic skin glands in the invasive species Lithobates catesbeianus (Anura:Ranidae)

2021 ◽  
pp. 1-11
Author(s):  
Sofia Agustina Maria Mancinelli ◽  
Araceli Rita Cóceres ◽  
Andrea Gabriela Pozzi ◽  
Lucas David Jungblut
Keyword(s):  
Invasive Species ◽  
The Body ◽  
Secretory Cells ◽  
Sexually Dimorphic ◽  
Amphibian Species ◽  
Skin Glands ◽  
Lithobates Catesbeianus ◽  
Body Regions ◽  
Intraspecific Communication ◽  
Scanning Electron

Abstract Males of most amphibian species possess specialized cutaneous glands, known as sexually dimorphic skin glands (SDSGs). SDSGs are usually clustered in specific body regions and are externally visible, but in some cases, external differences between males and females can be slight or absent, and the occurrence of SDSGs can only be disclosed by histological studies. Chemical signals produced by SDSGs markedly affect amphibian behaviour and reproduction, and therefore their occurrence, features, and location in the body could provide information on potential mechanisms of intraspecific communication in a particular species. In the present study, we perform light microscope (both histological and histochemical), and scanning electron microscope studies of skin samples from male and female adult specimens of the invasive bullfrog Lithobates catesbeianus, covering several body regions that could hold SDSGs. Most skin areas analysed showed only ordinary granular and mucous glands despite remarkable sexual dimorphism that could be externally observed. By contrast, the male nuptial pads contained exclusively SDSGs that were hypertrophied specialized mucous glands (SMGs), closely resembling breeding glands described in other anurans. Our histochemical study revealed that these SMGs contain heterogeneous populations of secretory cells, possibly involved in pheromone production. We discuss these characteristics of the SDSGs found in L. catesbeianus, as well as the surface specialization of the nuptial pads (achieved by scanning electron microscopy) in the light of their potential role in the chemical communication in this invasive species.

scholarly journals A new species of Cosmocerca (Nematoda, Ascaridomorpha) from the marine toad Rhinella marina (Linnaeus) (Anura, Bufonidae) in Australia

ZooKeys ◽  
2020 ◽  
Vol 931 ◽  
pp. 11-20
Author(s):  
Xue-Feng Ni ◽  
Diane P. Barton ◽  
Hui-Xia Chen ◽  
Liang Li
Keyword(s):  
Electron Microscopy ◽  
Scanning Electron Microscopy ◽  
New Species ◽  
Present Knowledge ◽  
The Body ◽  
Amphibian Species ◽  
Rhinella Marina ◽  
A New Species ◽  
Scanning Electron ◽  
Nematode Fauna

The marine toad Rhinella marina (Linnaeus) (Anura, Bufonidae) is a notorious, exotic amphibian species in Australia. However, our present knowledge of the composition of the nematode fauna of R. marina is still not complete. In the present study, a new cosmocercid nematode, Cosmocerca multipapillatasp. nov., was described using both light and scanning electron microscopy, based on specimens collected from R. marina in Australia. Cosmocerca multipapillatasp. nov. can be easily distinguished from its congeners by the body size, the presence of lateral alae and well sclerotized gubernaculum, the number and arrangement of plectanes and rosettes and the length of spicules, oesophagus and tail.

Morphology and distribution of sweat glands in the Cape fur seal, Arctocephalus pusillus pusillus (Carnivora:Otariidae)

2005 ◽  
Vol 53 (5) ◽  
pp. 295 ◽  
Author(s):  
L. S. Rotherham ◽  
M. van der Merwe ◽  
M. N. Bester ◽  
W. H. Oosthuizen
Keyword(s):  
Electron Microscopy ◽  
Scanning Electron Microscopy ◽  
Active Role ◽  
The Body ◽  
Sweat Glands ◽  
Body Regions ◽  
Fur Seal ◽  
Cape Fur Seal ◽  
Eccrine Sweat Glands ◽  
Scanning Electron

The present study examined whether sweat glands are present in the skin of the Cape fur seal, Arctocephalus pusillus pusillus. Sweat glands have an important role in thermoregulation; the presence or absence of sweat glands in the fur-covered and naked skin areas of the Cape fur seal was investigated using standard histological procedures and light and scanning electron microscopy. Sweat glands were present in both fur-covered and naked skin areas. The skin layers in the naked skin areas were thicker than those in the fur-covered areas, presumably to protect them against abrasions in the absence of hair. The density of apocrine sweat glands did not differ among the body regions; however, both apocrine and eccrine sweat glands were larger in naked skin areas than in fur-covered areas. This increased size of the glands suggests a more active role for the glands in the naked skin areas, and a higher heat-loss capability through evaporative cooling in these body regions.

scholarly journals SEM Study on Morphological Changes in Metarhizium anisopliae Infected Aphis craccivora Koch.

2016 ◽  
Vol 30 (1) ◽  
pp. 29
Author(s):  
Sarodee Boruah ◽  
Pranab Dutta ◽  
Joyarani Pegu ◽  
Himadri Kaushik ◽  
N. Gogoi ◽  
...  
Keyword(s):  
Metarhizium Anisopliae ◽  
Mycelial Growth ◽  
Morphological Changes ◽  
Aphis Craccivora ◽  
The Body ◽  
Body Parts ◽  
Body Regions ◽  
Fungal Propagules ◽  
Sem Study ◽  
Scanning Electron

Morphological changes in <em>Metarhizuim anisopliae</em> (Metschnikoff) Sorokin infected cow pea aphid, <em>Aphis craccivora</em> Koch were studied by scanning electron microscope (SEM). Aphids were caged on paired lantern chimney over cowpea twigs dipped in conical flasks with water infected and inoculated with fungal propagules of <em>M. anisopliae</em> at the concentration of 1X10<sup>6</sup> spores /ml of water. Infected aphids were observed under SEM and it showed severe cuticular damage, abnormalities in sensory systems as well as deformation of all the body parts. The hydrophobic conidia of <em>M. anisopliae</em> were found to attach to all body regions. It was evident that mycelial growth and conidiophores with conidia of <em>M. anisopliae</em> covered the body surface and penetrates inside the body of infested aphid causing damage to the pest by disturbing its major physiological activities leading to its death.

scholarly journals Allometric growth in meiofaunal invertebrates: do all kinorhynchs show homogeneous trends?

2019 ◽  
Vol 187 (4) ◽  
pp. 1041-1060
Author(s):  
Diego Cepeda ◽  
David Álamo ◽  
Nuria Sánchez ◽  
Fernando Pardos
Keyword(s):  
Mixed Model ◽  
Linear Mixed Model ◽  
Major Axis ◽  
The Body ◽  
Sexually Dimorphic ◽  
Positive Allometry ◽  
Mixed Model Approach ◽  
Body Regions ◽  
Reduced Major Axis ◽  
Taxonomic Groups

Abstract Allometry determines relevant modifications in metazoan morphology and biology and is affected by many different factors, such as ontogenetic constraints and natural selection. A linear mixed model approach and reduced major axis regression were used to explore evolutionary interspecific allometric trends between the total trunk length and the lengths of the segments and spines in the phylum Kinorhyncha at three taxonomic levels: the whole phylum, the class and the family. Statistically significant results were found in all the trunk segments, meaning that these body units grow proportionally correlated with the body, contrary to the results obtained for the spines. Developmental and morphophysiological constraints could lead to negative allometry in the first and last segments, because these body regions in kinorhynchs are essential to the implementation of some of the main biological functions, such as feeding and locomotion. The differential arrangement of cuticular appendages between the taxonomic groups considered seems to cause different evolutionary trends, because positive allometry may appear if a segment requires more space to accommodate a large number of organs and appendages, and vice versa. The presence of sexual dimorphism could also define positive allometry of a segment, owing to the need to harbour the sexually dimorphic appendages and their associated structures.

Analysis of the Anterior Secretory Cells of Onchidohs Muricata (Nudibranchia)

1981 ◽  
Vol 39 ◽  
pp. 614-615
Author(s):  
Roy Skidmore
Keyword(s):  
Endoplasmic Reticulum ◽  
Secretory Granules ◽  
Golgi Body ◽  
The Body ◽  
Secretory Cells ◽  
Secretory Vesicles ◽  
High Magnification ◽  
Large Numbers ◽  
Membrane Bound ◽  
Sole Of The Foot

The long-necked secretory cells in Onchidoris muricata are distributed in the anterior sole of the foot. These cells are interspersed among ciliated columnar and conical cells as well as short-necked secretory gland cells. The long-necked cells contribute a significant amount of mucoid materials to the slime on which the nudibranch travels. The body of these cells is found in the subepidermal tissues. A long process extends across the basal lamina and in between cells of the epidermis to the surface of the foot. The secretory granules travel along the process and their contents are expelled by exocytosis at the foot surface.The contents of the cell body include the nucleus, some endoplasmic reticulum, and an extensive Golgi body with large numbers of secretory vesicles (Fig. 1). The secretory vesicles are membrane bound and contain a fibrillar matrix. At high magnification the similarity of the contents in the Golgi saccules and the secretory vesicles becomes apparent (Fig. 2).

Scanning electron microscopy of freeze-fractured prescapular lymph node of caprine

1984 ◽  
Vol 42 ◽  
pp. 244-245
Author(s):  
O. Faroon ◽  
F. Al-Bagdadi ◽  
T. G. Snider ◽  
C. Titkemeyer
Keyword(s):  
Lymph Node ◽  
Lymph Nodes ◽  
Lymphatic System ◽  
Three Dimensional ◽  
Meat Products ◽  
The Body ◽  
Morphological Data ◽  
The World ◽  
Cellular Constituent ◽  
Scanning Electron

The lymphatic system is very important in the immunological activities of the body. Clinicians confirm the diagnosis of infectious diseases by palpating the involved cutaneous lymph node for changes in size, heat, and consistency. Clinical pathologists diagnose systemic diseases through biopsies of superficial lymph nodes. In many parts of the world the goat is considered as an important source of milk and meat products.The lymphatic system has been studied extensively. These studies lack precise information on the natural morphology of the lymph nodes and their vascular and cellular constituent. This is due to using improper technique for such studies. A few studies used the SEM, conducted by cutting the lymph node with a blade. The morphological data collected by this method are artificial and do not reflect the normal three dimensional surface of the examined area of the lymph node. SEM has been used to study the lymph vessels and lymph nodes of different animals. No information on the cutaneous lymph nodes of the goat has ever been collected using the scanning electron microscope.

X-ray micro tomography in the scanning electron microscope

1978 ◽  
Vol 36 (1) ◽  
pp. 106-107 ◽  
Author(s):  
W. Brünger
Keyword(s):  
Electron Beam ◽  
Electron Microscope ◽  
Scanning Electron Microscope ◽  
Target Surface ◽  
The Body ◽  
X Rays ◽  
Cross Sectional ◽  
X Ray ◽  
Micro Tomography ◽  
Scanning Electron

Reconstructive tomography is a new technique in diagnostic radiology for imaging cross-sectional planes of the human body /1/. A collimated beam of X-rays is scanned through a thin slice of the body and the transmitted intensity is recorded by a detector giving a linear shadow graph or projection (see fig. 1). Many of these projections at different angles are used to reconstruct the body-layer, usually with the aid of a computer. The picture element size of present tomographic scanners is approximately 1.1 mm2.Micro tomography can be realized using the very fine X-ray source generated by the focused electron beam of a scanning electron microscope (see fig. 2). The translation of the X-ray source is done by a line scan of the electron beam on a polished target surface /2/. Projections at different angles are produced by rotating the object.During the registration of a single scan the electron beam is deflected in one direction only, while both deflections are operating in the display tube.

The ultrastructure of the epidermis of the redia and cercaria of Parorchis acanthus, Nicoll. A study by scanning and transmission electron-microscopy

Parasitology ◽  
1971 ◽  
Vol 62 (3) ◽  
pp. 479-488 ◽  
Author(s):  
Gwendolen Rees
Keyword(s):  
Electron Micrographs ◽  
Technical Assistance ◽  
Ventral Surface ◽  
The Body ◽  
Muscle Fibres ◽  
Scanning Electron Micrographs ◽  
Large Area ◽  
Transmission Electron ◽  
Parorchis Acanthus ◽  
Scanning Electron

Scanning electron-micrographs have shown the covering of microvilli on the surface of the redia of Parorchis acanthus. In the contracted state the elongated microvilli with bulbous extremities seen in the surface grooves may be the result of compression. The surface of the epidermis of the cercaria is smooth on a large area of the ventral surface and lattice-like with microvilli, laterally, anteriorly, dorsally and on the tail. The spines on the body can be withdrawn into sheaths by the contraction of muscle fibres inserted into the basement lamina below each spine.I would like to express my sincere gratitude to Dr I. ap Gwynn of this department for preparing the scanning electron-micrographs and the School of Engineering Science, University of North Wales, Bangor for the use of their stereoscan. I should also like to thank Mr M. C. Bibby for technical assistance and Professor E. G. Gray and Dr W. Sinclair for assistance with the transmission electron-micrographs.

scholarly journals CHANGES IN FINE STRUCTURE DURING SILK PROTEIN PRODUCTION IN THE AMPULLATE GLAND OF THE SPIDER ARANEUS SERICATUS

1969 ◽  
Vol 42 (1) ◽  
pp. 284-295 ◽  
Author(s):  
Allen L. Bell ◽  
David B. Peakall
Keyword(s):  
Fine Structure ◽  
Epithelial Cells ◽  
Protein Production ◽  
Distal Portion ◽  
Silk Gland ◽  
The Body ◽  
Single Type ◽  
Secretory Cells ◽  
The Web ◽  
Tunica Intima

The ampullate silk gland of the spider, Araneus sericatus, produces the silk fiber for the scaffolding of the web. The fine structure of the various parts of the gland is described. The distal portion of the duct consist of a tube of epithelial cells which appear to secrete a substance which forms the tunica intima of the duct wall. At the proximal end of the duct there is a region of secretory cells. The epithelium of the sac portion contains five morphologically distinct types of granules. The bulk of the synthesis of silk occurs in the tail of the gland, and in this region only a single type of secretory droplet is seen in the epithelium. Protein synthesis can be stimulated by the injection of 1 mg/kg acetylcholine into the body fluids. 10 min after injection, much of the protein stored in the cytoplasm of the epithelial cells has been secreted into the lumen. 20 min after stimulation, the ergastoplasmic sacs form large whorls in the cytoplasm. Protein, similar in electron-opacity to protein found in the lumen, begins to form in that portion of the cytoplasm which is enclosed by the whorls. The limiting membrane of these droplets is formed by ergastoplasmic membranes which lose their ribosomes. No Golgi material has been found in these cells. Protein appears to be manufactured in the cytoplasm of the tail cells in a form which is ready for secretion.

Preparation of Alcohol-Preserved Larvae of Culicidae (Diptera) for Scanning Electron Microscopy

1972 ◽  
Vol 3 (3) ◽  
pp. 181-188 ◽  
Author(s):  
Christine Dahl
Keyword(s):  
Electron Microscopy ◽  
Scanning Electron Microscopy ◽  
Electron Microscope ◽  
Scanning Electron Microscope ◽  
The Body ◽  
Taxonomic Studies ◽  
Scanning Electron ◽  
Sem Studies

AbstractA method for preparation of alcohol-preserved culicid larvae for Scanning Electron Microscope (SEM) studies is described. It is based on dehydration by ethanol-xylol and fast evaporation of xylol in +8o° C. for ten minutes. For taxonomic studies such as examination of pecten teeth, comb scales and microtrichiae in magnifications up to 6oooX the method is suitable. For studies of receptor structures on hair-tufts and microstructures of the body integument alcohol preserved material is less satisfactory. The microstructure of the comb scales is figured and their function discussed. Differences in the ultrastructure of the abdominal hair-tufts are pointed out.

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