The Function of Chromatocytes in the Simuliidae, with Notes on their Behaviour at the Pupal-adult Moult

1959 ◽  
Vol s3-100 (49) ◽  
pp. 65-71
Author(s):  
H. E. HINTON
Keyword(s):  
Basement Membrane ◽  
Adult Development ◽  
Larval Growth ◽  
The Body ◽  
Colour Pattern ◽  
Pigment Granules ◽  
Accumulation Of Lipids ◽  
Photographic Records

In the larvae and pupae of the Simuliidae the cuticle and epidermis of the thorax and abdomen are more or less transparent, and the colour pattern is formed by cells (chromatocytes) that contain pigment granules., These cells always lie below the basement membrane. It is possible to photograph the chromatocytes without damage to the animal and thus to make photographic records of the behaviour of particular chromatocytes over a period of many days when the animal is moving about and feeding in the normal way. The chromatocytes accumulate lipids. The accumulation of lipids during larval growth and their depletion during adult development has been photographed in normal undamaged animals. Conspicuous changes in the colour pattern, especially of the thorax, occur at metamorphosis. Such changes are due to mass migrations and the formation of new aggregation patterns by the chromatocytes. While such movements of the chromatocytes are taking place in some parts of the body, the aggregation patterns of chromatocytes in other parts of the body remain unchanged and appear to be unaffected by the events that initiate and accompany moults and ecdyses.

An Ultrastructural Study of Pericytes

1968 ◽  
Vol 26 ◽  
pp. 66-67
Author(s):  
T. M. Murad ◽  
E. von Haam
Keyword(s):  
Plasma Membrane ◽  
Endothelial Cell ◽  
Basement Membrane ◽  
Blood Vessel ◽  
Vascular Endothelial Cells ◽  
Myoepithelial Cells ◽  
Capillary Blood ◽  
The Body ◽  
Capillary Blood Vessel ◽  
Outer Plasma Membrane

Pericytes are vascular satellites present around capillary blood vessels and small venules. They have been observed in almost every tissue of the body and are thought to be related to vascular smooth muscle cells. Morphologically pericytes have great similarity to vascular endothelial cells and also slightly resemble myoepithelial cells.The present study describes the ultrastructural morphology of pericytes in normal breast tissue and in benign tumor of the breast. The study showed that pericytes are ovoid or elongated cells separated from the endothelial cell of the capillary blood vessel by the basement membrane of endothelial cell. The nuclei of pericytes are often very distinctive. Although some are round, oval, or elongated, others show marked irregularity and infolding of the nuclear membrane. The cytoplasm shows mono-or bipolar extension in which the cytoplasmic organelles are located (Fig. 1). These cytoplasmic extensions embrace the capillary blood vessel incompletely. The plasma membrane exhibits multiple areas of focal condensation called hemidesmosomes (Fig. 2, arrow). A variable number of pinocytotic vesicles are frequently seen lining the outer plasma membrane. Normally pericytes are surrounded by a basement membrane which is found more consistently on the outer plasma membrane separating the pericytes from the stromal connective tissue.

A possible function of the caudal spot in characid fishes

1977 ◽  
Vol 55 (7) ◽  
pp. 1063-1066 ◽  
Author(s):  
J. D. McPhail
Keyword(s):  
The Body ◽  
Colour Pattern ◽  
Selective Basis ◽  
The Difference

The suggestion that caudal pigment spots in fishes can act as deflection marks is tested experimentally. Fish with artificial caudal spots escape predators more often than the same species without spots, but the difference was not significant (0.1 < p < 0.2). However in fish captured, the place on the body where the fish was seized was shifted posteriorly by the presence of a spot (p < 0.01). Although the results are equivocal, they do suggest a possible selective basis for convergence in colour pattern in small characid fishes.

Memoirs: Peristalsis in the Malpighian Tubules of Diptera, Preliminary Account: with a note on the Elimination of Calcium Carbonate from the Malpighian Tubules of Drosophila Funebris

1925 ◽  
Vol s2-69 (275) ◽  
pp. 385-398
Author(s):  
L. EASTHAM
Keyword(s):  
Calcium Carbonate ◽  
Basement Membrane ◽  
Longitudinal Muscle ◽  
The Body ◽  
Malpighian Tubules ◽  
Preliminary Account ◽  
Longitudinal Muscles ◽  
Adult Drosophila

1. The proximal regions of the Malpighian tubules of Drosopbila funebris and Calliphora erythro cephala are supplied with systems of circular and longitudinal muscles external to the basement membrane. 2. These muscles are continuous with those of the mid-gut. 3. There is a terminal muscle to each anterior tubule in Drosophila funebris connected to the alar muscles of the pericardial septum. 4. Peristalsis has been observed in the proximal regions of the tubules, caused by the circular muscles. 5. The tubules exhibit a waving movement, probably due to the longitudinal muscle-bands of the lower or proximal ends of the tubules. 6. Calcium carbonate is stored in the terminal portions of the anterior tubules of Drosophila funebris. 7. This calcium carbonate is not eliminated at the beginning of metamorphosis, but is passed to the gut about the sixth day of pupal life, and is only expelled from the body on the emergence of the adult. 8. Calcium carbonate is found in the Malpighian tubules of the adult Drosophila funebris.

Two new annual fishes (Cyprinodontiformes: Rivulidae) unexpectedly discovered in the highlands of southern Brazil

Zootaxa ◽  
2021 ◽  
Vol 4949 (3) ◽  
pp. 499-520
Author(s):  
LUIS ESTEBAN KRAUSE LANÉS ◽  
MATHEUS VIEIRA VOLCAN ◽  
LEONARDO MALTCHIK
Keyword(s):  
New Species ◽  
Conservation Status ◽  
The Body ◽  
Colour Pattern ◽  
Southern Brazil ◽  
Body Depth ◽  
Body Contact ◽  
Morphometric Features ◽  
Natural Grassland ◽  
Two Populations

Two new species of Austrolebias are described based on specimens collected from temporary pools located in natural grassland landscape within the Araucaria Forest domain at exceptionally high altitudes (~1000 meters a.s.l.). Austrolebias botocudo sp. n. and Austrolebias nubium sp. n. occur, respectively, in drainages of upper rio Apuaê-Inhandava (upper rio Uruguay basin) and upper rio Taquari-Antas (upper rio Jacuí, Laguna dos Patos basin), in the Meridional Plateau of southern Brazil. Despite an intensive survey conducted in the area, only two populations of each species were recorded. Both new species occurs at altitudes that are among the higher recorded for species of the genus, and both are assigned to the subgenus Acrolebias. The new species described herein are easily distinguished for its congeners by the colour pattern of males, by presence of melanophores irregularly distributed in different parts of the body, contact organs cover the body and anal fins, position of fins related with vertebrae, by preopercular and mandibular series of neuromasts united, by a series of morphometric features and by larger maximum standard length. Austrolebias botocudo and A. nubium are distinguished from each other by colour pattern of males, length of contact organs in the flank and number of contact organs in scales of lateral line, dorsal profile of head, number of neuromasts in the preopercular + mandibular series, body depth in females, and by basihyal cartilage length. Additionally, we discuss the conservation status of the new species, and provided an identification key for the species of the subgenus Acrolebias. 

scholarly journals Can't tell the caterpillars from the trees: countershading enhances survival in a woodland

2008 ◽  
Vol 275 (1651) ◽  
pp. 2539-2545 ◽  
Author(s):  
Hannah M Rowland ◽  
Innes C Cuthill ◽  
Ian F Harvey ◽  
Michael P Speed ◽  
Graeme D Ruxton
Keyword(s):  
Visual Cues ◽  
Field Experiments ◽  
Three Dimensional ◽  
Shape From Shading ◽  
The Body ◽  
Colour Pattern ◽  
Free Living ◽  
Background Matching ◽  
Lepidopteran Larvae ◽  
Beech Tree

Perception of the body's outline and three-dimensional shape arises from visual cues such as shading, contour, perspective and texture. When a uniformly coloured prey animal is illuminated from above by sunlight, a shadow may be cast on the body, generating a brightness contrast between the dorsal and ventral surfaces. For animals such as caterpillars, which live among flat leaves, a difference in reflectance over the body surface may degrade the degree of background matching and provide cues to shape from shading. This may make otherwise cryptic prey more conspicuous to visually hunting predators. Cryptically coloured prey are expected to match their substrate in colour, pattern and texture (though disruptive patterning is an exception), but they may also abolish self-shadowing and therefore either reduce shape cues or maintain their degree of background matching through countershading: a gradation of pigment on the body of an animal so that the surface closest to illumination is darker. In this study, we report the results from a series of field experiments where artificial prey resembling lepidopteran larvae were presented on the upper surfaces of beech tree branches so that they could be viewed by free-living birds. We demonstrate that countershading is superior to uniform coloration in terms of reducing attack by free-living predators. This result persisted even when we fixed prey to the underside of branches, simulating the resting position of many tree-living caterpillars. Our experiments provide the first demonstration, in an ecologically valid visual context, that shadowing on bodies (such as lepidopteran larvae) provides cues that visually hunting predators use to detect potential prey species, and that countershading counterbalances shadowing to enhance cryptic protection.

scholarly journals PERTUMBUHAN LARVA DAN PRODUKSI BENIH IKAN KERAPU BEBEK Cromileptes altivelis Valenciennes, 1828 HASIL BUDIDAYA TURUNAN KE-3

2018 ◽  
Vol 10 (3) ◽  
pp. 589-600
Author(s):  
Regina Melianawati ◽  
Ni Wayan Widya Astuti ◽  
. Tridjoko
Keyword(s):  
Body Weight ◽  
Survival Rate ◽  
Seed Production ◽  
Larval Growth ◽  
The Body ◽  
Third Generation ◽  
Larval Body ◽  
Spine Length ◽  
The Third ◽  
Total Length

ABSTRAKKetersediaan induk dalam suatu usaha pembenihan memiliki peran yang sangat penting. Namun demikian, ketersediaan induk yang berasal dari alam sangat terbatas jumlahnya, sehingga perlu dilakukan penyediaan calon induk yang berasal dari hasil budidaya. Ikan kerapu bebek Cromileptes altivelis Valenciennes, 1828 turunan pertama (F-1) dan turunan kedua (F-2) sudah dapat diproduksi dari hasil budidaya, namun benih turunan ketiga (F-3) belum dapat diperoleh. Penelitian ini bertujuan untuk mendapatkan karakteristik morfologis dan pertumbuhan larva ikan kerapu bebek F-3 sebagai calon induk F-3, serta tingkat keberhasilan produksi benihnya. Pemeliharaan larva dilakukan dalam hatchery hingga larva menjadi benih. Parameter yang diamati meliputi panjang total dan panjang duri sirip larva, berat tubuh larva serta sintasan dan jumlah produksi benih. Hasil penelitian menunjukkan bahwa panjang total larva umur 5, 15, 25 dan 35 hari, masing-masing adalah 3,20±0,07; 4,42±1,11; 8,35±1,12 dan 12,51±3,23 mm. Duri sirip mulai terukur pada larva umur 15 hari. Berat larva umur 30 hari adalah 0,11±0,04 g. Pola pertumbuhan panjang total dan berat tubuh larva adalah eksponensial, sedangkan pola pertumbuhan duri siripnya adalah linier. Masa pemeliharaan larva hingga menjadi benih adalah ± 40 hari. Jumlah benih ikan kerapu bebek F-3 yang diproduksi dalam satu kali siklus pemeliharaan berkisar 440 hingga 2.300 ekor dari 50 ekor induk dan 3 kali siklus pemijahan dengan tingkat kelangsungan hidup 1,30% hingga 8,80%. Hasil penelitian ini mengindikasikan bahwa ikan kerapu bebek F-3 dapat diproduksi dari hasil budidaya seperti halnya pada F-1 dan F-2. ABSTRACTBroodstocks are the most important part of humpback grouper culture, but their availability in nature are limited. Therefore, it is necessary to produce broodstock candidates from culture. The first (F-1) and the second (F-2) generation of humpback grouper have already been produced but the third generation (F-3) production is still on the way. This study was conducted to find out morphological characteristic of the third generation (F-3) of humpback grouper larvae as the candidate of the third generation of broodstock, larval growth and the success rate of seed production. Larvae rearing was done in hatchery until larvae metamorphosed to be seeds. Observed variables including larval total length and spine length, larval body weight, survival rate and the juvenile productions. The study result showed the total length of 5, 15, 25 and 35 days old larvae were 3.20±0.07; 4.42±1.11; 8.35±1.12 and 12.51±3.23 mm, respectively. The spine began measured on 15 days old larvae. The body weight of 30 days old larvae was 0.11±0.04 g. The growth pattern of larval total length and body weight were exponential, while the growth of spine was linear. Rearing period from larvae to juveniles was 40 days. Number of F-3 seed production of humpback grouper produced from once rearing cycle range between 440 and 2,300 fish and the survival rate range from 1.30% up to 8.80%. Therefore, this study could indicate that seed of F-3 humpback grouper can be produced as those of F-1 and F-2.

Hydrophis donaldi (Elapidae, Hydrophiinae), a highly distinctive new species of sea snake from northern Australia

Zootaxa ◽  
2012 ◽  
Vol 3201 (1) ◽  
pp. 45 ◽  
Author(s):  
KANISHKA D.B. UKUWELA ◽  
KATE L. SANDERS ◽  
BRYAN G. FRY
Keyword(s):  
New Species ◽  
Habitat Preferences ◽  
The Body ◽  
Colour Pattern ◽  
Northern Australia ◽  
Nucleotide Substitutions ◽  
Sea Snake ◽  
Sea Snakes ◽  
Morphological Diagnosis ◽  
By Catch

A new species of viviparous sea snake, Hydrophis donaldi sp. nov. (Hydrophiinae), is described from the Gulf of Carpen-taria, northern Australia. Molecular analyses reveal this species as a deeply divergent lineage within the Hydrophis sub-group, and separate it from all other sampled taxa by fixed nucleotide substitutions at three independent mitochondrial andnuclear loci. The new species is assigned to Hydrophis based on the current morphological diagnosis of this large but pa-raphyletic genus, and is distinguished from all other Hydrophis species and closely allied genera by a combination of mor-phological characters relating to scalation, colour pattern and osteology. Using current keys for sea snakes, H. donaldi sp.nov. might be mistaken for H. coggeri, H. sibauensis or H. torquatus diadema but it is readily distinguished from thesespecies by a higher number of bands on the body and tail, lower ventral count, strongly spinous body scales, and a wider,more rounded head. Sea snakes have been sampled intensively in the Gulf of Carpentaria due to their vulnerability to by-catch in the region’s commercial prawn-trawl fisheries. That this highly distinctive new species has evaded discovery inthe region until now is surprising, but might be explained by its habitat preferences. All known specimens of H. donaldi sp. nov. were found in estuarine habitats that are relatively poorly surveyed and are not targeted by commercial fisheries.

The relation between connective tissue cells and intercellular substances, including basement membranes

1975 ◽  
Vol 271 (912) ◽  
pp. 363-377 ◽  
Keyword(s):  
Endothelial Cells ◽  
Basement Membrane ◽  
Immune Complexes ◽  
Hydrolytic Enzymes ◽  
Inflammatory Cells ◽  
Cell Types ◽  
Cellular Level ◽  
Basement Membranes ◽  
The Body ◽  
Pathological Changes

Basement membranes are distributed widely in the body forming an extracellular matrix for epithelial and endothelial cells. The collagenous and glycoprotein constituents of basement membranes are synthesized by these two cell types. Disturbance of the interactions between basement membranes and their associated epithelial and endothelial cells can lead to the pathological changes seen in diseases involving basement membranes. These changes are illustrated here by reference to glomerulonephritis induced by the deposition of immune complexes in the glomerulus of the kidney, and chronic inflammatory changes occurring in the lung after inhalation of asbestos. In these diseases basement membrane changes can occur in several ways. Hydrolytic enzymes released from inflammatory cells degrade basement membranes while other factors released from these cells may stimulate synthesis of basement membrane constituents by epithelial and endothelial cells. Alternatively the physical separation of epithelial and endothelial cells from their basement membranes by space-occupying substances such as immune complexes can interfere with feedback mechanisms leading to synthesis of basement membrane constituents and cell proliferation. Studies of these pathological changes at a cellular level should shed new light on the ways in which cells interact with their pericellular environment.

The subterranean Aenigmachanna gollum, a new genus and species of snakehead (Teleostei: Channidae) from Kerala, South India

Zootaxa ◽  
2019 ◽  
Vol 4603 (2) ◽  
pp. 377 ◽  
Author(s):  
RALF BRITZ ◽  
V.K. ANOOP ◽  
NEELESH DAHANUKAR ◽  
RAJEEV RAGHAVAN
Keyword(s):  
New Genus ◽  
South India ◽  
Dna Barcode ◽  
The Body ◽  
Colour Pattern ◽  
Slight Reduction ◽  
New Genus And Species ◽  
Body Depth ◽  
The Family ◽  
Maximum Body

Aenigmachanna gollum, new genus and species, is described from Kerala, South India. It is the first subterranean species of the family Channidae. It has numerous derived and unique characters, separating it from both the Asian Channa Scopoli and the African Parachanna Teugels & Daget. Uniquely among channids, A. gollum has a very slender (maximum body depth only 11.1–11.3% SL), eel-like body (head length 20.8–21.6% SL), large mouth (jaw length 60.4–61.1 % HL), 43–44 anal-fin rays, 83–85 scales in a lateral series, an unusual colour pattern and it lacks pored lateral-line scales on the body and body buoyancy. In addition, it is distinguished by its DNA barcode sequence, which is 15.8–24.2% divergent from other species of the family Channidae. Morphological modifications usually associated with a subterranean life, such as reduction of eyes and enhancement of non-visual senses (taste, smell, mechanosensory systems) are absent in A. gollum. However, it shares with subterranean fishes a slight reduction of its pigmentation in comparison to epigean channids.

scholarly journals Hypermetabolic Conversion of Plant Oil into Water: Endothermic Biochemical Process Stimulated by Juvenile Hormone in the European Firebug, Pyrrhocoris apterus L.

2016 ◽  
Vol 8 ◽  
pp. IJIS.S40566 ◽  
Author(s):  
Karel Sláma ◽  
Jan Lukáš
Keyword(s):  
Juvenile Hormone ◽  
Fat Body ◽  
Larval Growth ◽  
Living Organism ◽  
Dietary Lipid ◽  
The Body ◽  
Plant Oil ◽  
Pyrrhocoris Apterus ◽  
Dry Food ◽  
Metabolic Water

The physiological and biochemical mechanisms that enable insects to feed on dry food to secure enough water for larval growth were investigated. The study was carried out with a plethora of physiological methods, ranging from the simple volumetric determination of O2 consumption and water intake to more advanced methods such as scanning microrespirography and thermovision imaging of insect's body temperature. The experiments were done on the European firebug, Pyrrhocoris apterus, which feeds exclusively on dry linden seeds. In order to survive, it needs to drink water or suck a sap from plants occasionally. It was found that the young larval instars compensate the occasional water deficiency by the increased production of metabolic water. The juvenile hormone (JH)-dependent production of metabolic water, which was previously found in other species consuming dry food, was achieved in P. apterus by total metabolic combustion of the dietary lipid (neutral seed oil). The water-producing, hypermetabolic larvae were heated from inside by endothermic energy released from the uncoupling of oxidation from oxidative phosphorylation. The “warm”, hypermetabolic larvae burning the dietary oil into CO2 and water showed the increased rates of respiratory metabolism. Microrespirographic recording of these larvae revealed the ratio of the respiratory quotient (RQ, CO2/O2) of 0.7, which indicated the breakdown of a pure triglyceride. The warm hypermetabolic larvae could be easily spotted and distinguished from the “cold” larvae on the screen of a thermovision camera. The last instar larvae lacking the JH were always only cold. They metabolized a carbohydrate substrate exclusively (RQ = 1.0), while the dietary lipid was stored in the fat body. In comparison with the hypermetabolic larvae of some other species fed on dry food, which exhibited the highest rates of O2 consumption ever recorded in a living organism (10–20 mL O2/g per hour), the metabolic difference between the warm and cold larvae of P. apterus was only some 30% (not a reported 10-fold difference), which was presumably due to their ability to drink. We conclude that a very important, though still largely neglected, epigenetic biochemical role of insect JH depends on switchover between the utilization of dietary lipid (+JH; production of metabolic water) and carbohydrate (-JH; lipid storage in the fat body). The hypermetabolic water supply in insects fed on dry food, which is associated with enormous rates of O2 consumption, liberates endothermic energy that heats the body and potentially influences the insect thermoregulation. A possibility that the JH-dependent lipolytic hormone stimulates the total metabolic breakdown of nutritional lipids may be absolutely different from the currently known adipokinetic peptides that have been emphasized.

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