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O crescimento de Parastacus defossus (Crustacea: Decapoda: Parastacidae)
Noro, Clarissa K.;Buckup, Ludwig;
Zoologia (Curitiba) , 2009, DOI: 10.1590/S1984-46702009000100009
Abstract: the present study investigates the growth of parastacus defossus faxon, 1898, a fossorial species known only from brazil (state of rio grande do sul) and uruguay. the estimated growth curve was calculated for animals from the wild and for juveniles cultivated in the laboratory. the specimens were collected monthly between january, 2003 to august, 2005, in lami region, municipality of porto alegre, state of rio grande do sul, brazil. the von bertalanffy (1938) growth model was used to estimate the growth curve . to calculate the modal values from the frequency distributions the software peakfit 4.12? seasolve inc., was employed. the growth curve for field animals is described by the equation: lt = 30,98 [1 - e-0,0026 (t+44,86)] and for the juveniles cultivated in laboratory: lt = 19,29 [1 - e-0,0048 (t+37,14)]. it was shown that, under laboratory conditions, the growth was slower than in the field. by comparing the data of p. defossus with those of p. brasiliensis (von martens, 1869), it was possible to verify a slower growth, both in laboratory as under field conditions. the longevity of the studied species (1198.7 days or 40 months) also showed to be lower when compared to p. brasiliensis.
Estrutura populacional e biologia reprodutiva de Parastacus defossus (Crustacea: Decapoda: Parastacidae)
Noro, Clarissa K.;Buckup, Ludwig;
Revista Brasileira de Zoologia , 2008, DOI: 10.1590/S0101-81752008000400007
Abstract: this study investigates the population structure and the reproductive biology of parastacus defossus faxon, 1898, a fossorial species that spends its life inside subterranean tunnels. around 30 specimens were collected each month in the region of lami, municipality of porto alegre, state of rio grande do sul, brazil, from january, 2003 to august, 2005. the minimum, the maximum, and the mean carapace length of males, females, juveniles and individuals with ootestis were recorded. the frequency distribution by size classes, the sexual proportion, the recruitment, and the reproductive period were analyzed. a total of 766 specimens were collected, from which 315 were males (41.12%), 278 were females (36.30%), 166 were juveniles (21.67%), and seven individuals had ootestis (0.91%). males and females were present in all months and in all size classes. the highest frequency of individuals matched the size classes from 24 to 30 mm. the highest frequency of juveniles was recorded during the spring of 2003 and the summer 2005. significant differences in the size of males and females were recorded in the size classes between 26 and 30 mm. the sex ratio between all males and females was 1:0.88 (x2 = 2.3, p > 0.05). the proportion between males and females showed significant differences between the size classes 26-28 mm (x2 = 5.43, p < 0.05) and 28-30 mm (x2 = 4.77, p < 0.05) carapace length, were the number of males was highest. of the 278 females, only 17 were ovigerous (6.11%) and the reproductive period was clearly restricted to the spring.
Morfologia setal de Parastacus brasiliensis (von Martens) (Crustacea, Decapoda, Parastacidae)
Horn, Ana Cristina Moura;Buckup, Ludwig;
Revista Brasileira de Zoologia , 2004, DOI: 10.1590/S0101-81752004000400006
Abstract: the family parastacidae comprises the limnic crustaceans popularly known as crayfishes or crawfishes. parastacus huxley, 1879 is the only genus occurring in brazil and has an endemic species, parastacus brasiliensis (von martens,1869), in rio grande do sul state. the individuals were collected with traps from a brook in the springs of gravataí basin, taquara, rio grande do sul state, brazil. the captured animals were taken to the universidade federal do rio grande do sul carcinology laboratory and raised to full growth in aquaria. the specimens were dissected, and the setae analysed under optical microscopy and drawn with the aid of a camera lucida. material was prepared for photography under scanning electron microscope. the analysis and classification of all types of setae in the adult forms of p. brasilieinsis was performed.
Morfologia externa de Parastacus brasiliensis (Decapoda, Parastacidae)
Horn, Ana Cristina M.;Buckup, Ludwig;Noro, Clarissa K.;Barcelos, Daniela F.;
Iheringia. Série Zoologia , 2008, DOI: 10.1590/S0073-47212008000100019
Abstract: parastacus brasiliensis (von martens, 1869) is an endemic south brazilian freshwater crayfish that occurs in the river systems belonging to the guaíba estuary, in the central lowlands of the state of rio grande do sul. the aim of this study is to describe and illustrate the external morphology and the distribution of the different types of setae on the appendages of adult p. brasiliensis. in laboratory, the specimens were dissected and the details of the morphological organization described and drawn with a camara lucida adapted to a stereomicroscope. a scanning electron microscope was utilized for a more detailed study of the setae. the results were compared with other crayfish species and also with the juvenile stages of p. brasiliensis. the types and the distributional pattern of the setae observed are similar to austropotamobius pallipes (lereboullet, 1858). differences were found in the basipodite and the coxopodite of the first maxilliped and in the first maxilla of p. brasiliensis, where the serrate setae are replaced by the plumodenticulate and multidenticulate forms.
Intersexualidad en el camarón excavador Parastacus pugnax (Poeppig, 1835) (Decapoda, Parastacidae)
Rudolph,Erich H.;
Investigaciones marinas , 1997, DOI: 10.4067/S0717-71781997002500002
Abstract: abstract. the problem of intersexuality was studied in the burrowing crayfish parastacus pugnax (poeppig, 1835) by examination of sexual characters of 538 specimens captured in nehuentúe, chile. it was demostrated that in this species both male and female are intersex, with supernumerary gonopores and with single gonad -either male or female- from which emerge gonoducts of both sexes to the respective gonopores. in males the oviducts are rudimentary and female gonopores are semiellipsoidal, with a very calcified cover. in females the sperm ducts are rudimentary and female gonopores are ellipsoidal and covered by a noncalcified membrane or just partially calcified. permanent secondary sexual characters associated with incubation of eggs were identified in females. the adaptive value of this type of genitalia is discussed in the evolutionary historical context of parastacidae
Intersexualidad en el camarón excavador Parastacus pugnax (Poeppig, 1835) (Decapoda, Parastacidae) Intersexuality in the burrowing crayfish Parastacus pugnax (Poeppig, 1835) (Decapoda, Parastacidae  [cached]
Erich H. Rudolph
Investigaciones Marinas , 1997,
Abstract: Se estudió el problema de intersexualidad en el camarón excavador Parastacus pugnax (Poeppig, 1835), a través del examen de los caracteres sexuales de 538 ejemplares capturados en Nehuentúe, Chile. Se demostró que en esta especie machos y hembras son intersexo, con gonoporos supernumerarios y con una gónada única -masculina o femenina según el caso- de la cual emergen gonoductos de ambos sexos hacia los respectivos gonoporos. En los machos los oviductos son rudimentarios y los gonoporos femeninos son semielipsoidales, con una cubierta muy calcificada. En las hembras los espermiductos son rudimentarios y los gonoporos femeninos son elipsoidales y cubiertos por una membrana no calcificada o sólo parcialmente calcificada. En las hembras se identificaron caracteres sexuales secundarios permanentes asociados a la incubación de los huevos. Se discute el valor adaptativo de este tipo de genitalia en el contexto de la historia evolutiva de los Parastacidae ABSTRACT. The problem of intersexuality was studied in the burrowing crayfish Parastacus pugnax (Poeppig, 1835) by examination of sexual characters of 538 specimens captured in Nehuentúe, Chile. It was demostrated that in this species both male and female are intersex, with supernumerary gonopores and with single gonad -either male or female- from which emerge gonoducts of both sexes to the respective gonopores. In males the oviducts are rudimentary and female gonopores are semiellipsoidal, with a very calcified cover. In females the sperm ducts are rudimentary and female gonopores are ellipsoidal and covered by a noncalcified membrane or just partially calcified. Permanent secondary sexual characters associated with incubation of eggs were identified in females. The adaptive value of this type of genitalia is discussed in the evolutionary historical context of Parastacidae
Aspectos anat?micos e funcionais do aparelho reprodutor de Parastacus brasiliensis (von Martens) (Crustacea, Decapoda, Parastacidae)
Almeida, Alexandre Oliveira de;Buckup, Ludwig;
Revista Brasileira de Zoologia , 1997, DOI: 10.1590/S0101-81751997000200017
Abstract: the absence of morphological external characteristics that allow the recognition of the sex as well as the presence of both male and female gonopores in the same animal [except in some sexual forms of parastacus nicoleti (philippi, 1882)] gives rise to the hypothetical existence of some form of hermaphroditism in crayfishes belonging to the genus parastacus huxley, 1879. specimens of parastacus brasiliensis (von martens, 1869) were collected in a rivulet at mariana pimentel municipality, rio grande do sul, brazil. in the laboratory they were reared and dissected. the results suggest that p. brasiliensis may be a sequential hermaphroditic species, but male and female gonadal tissues were not simultaneously present in the analized samples. in testes and ovaries two pairs of genital ducts are present; that connect, respectively, to the gonopores on the coxae of the fifth and the third pairs of pereiopods. in the females only the apertures and anterior ducts seem to be functional, while in the males only the apertures and posterior ducts may be functional. the existence of different degrees of obstruction in the female genital apertures and different degrees of projection in the male genital apertures was observed. the aspect of the gonopores were used to recognize, externally, the sex of animais.
Dinamica do desenvolvimento das g?nadas de Parastacus varicosus (Crustacea, Decapoda, Parastacidae)
Castiglioni, Daiana da Silva;Oliveira, Guendalina Turcato de;Bond-Buckup, Georgina;
Iheringia. Série Zoologia , 2006, DOI: 10.1590/S0073-47212006000400004
Abstract: the level of gonadal development of a species can be evaluated by the determination of the gonadossomatic (gsi) and the hepatossomatic (hsp) indices. the hepatopancreas is the most important centre for storage of reserves in decapods, which can be transferred to the gonads during their development. the aim of this study was to estimate gonadal development of parastacus varicosus faxon, 1898 by means of macro and microscopic observations, as well by the inspection of the variations of gonadossomatic and hepatossomatic indices. the crayfishes were collected in the gravataí hydrographic basin, cova do touro locality, state of rio grande do sul, brazil. female's gonads were weighted for the recognition of the gonadossomatic index and histological analysis. hepatopancreas weight was also obtained to determine the hepatossomatic index. the results showed a decrease of the hepatossomatic index and an increase of the gonadossomatic index in females during the seasonal transition period from spring to summer, suggesting a possible transfer of the hepatopancreatic reserves to the gonads during the reproductive period. however, considering that this decrease did not show significance at p>0.05 level, it is likely that other tissues contribute for this transfer, as hemolymph, for instance.
Seasonal variations in the intermediate metabolism of the crayfish Parastacus brasiliensis (Crustacea, Decapoda, Parastacidae) in the natural environment and experimental culture
Dutra, Bibiana K.;Zank, Caroline;Silva, Karina M. da;Conter, Maria R.;Oliveira, Guendalina T.;
Iheringia. Série Zoologia , 2008, DOI: 10.1590/S0073-47212008000300010
Abstract: the goal of this study was to evaluate the effects of seasonal variations on energy metabolism in different tissues of the freshwater crayfish parastacus brasiliensis (von martens, 1869). crayfish were collected monthly from january 2001 to january 2003 in s?o francisco de paula, rio grande do sul, brazil, in a stream and in a culture tank. haemolymph samples were collected from each crayfish in the field with a syringe, by puncturing the membrane at the base of the chelipeds. hepatopancreas, gills, and abdominal muscle were removed for determination of free glucose, glycogen, total lipids, and triglycerides. the haemolymph samples were used for determination of glucose, total proteins, total lipids, and triglycerides. statistical analysis revealed significant differences in biochemical composition in crayfish collected in the stream compared to the experimental tank during the year, principally in glucose and triglycerides in haemolymph, glycogen and total lipids in all tissues study, and triglycerides only in abdominal muscle. the regular food intake partially modified these seasonal variations of the metabolic pattern. environmental conditions (e.g., food availability and water temperature) and reproductive period appeared to be the main factors influencing the seasonal patterns of variation in energy metabolism.
Seasonal variation of the effect of high-carbohydrate and high-protein diets on the intermediate metabolism of Parastacus brasiliensis (Crustacea, Decapoda, Parastacidae) maintained in the laboratory
Dutra, Bibiana K.;Silva, Karina M. da;Zank, Caroline;Conter, Maria R.;Oliveira, Guendalina T.;
Iheringia. Série Zoologia , 2008, DOI: 10.1590/S0073-47212008000400003
Abstract: the goal of this study was to evaluate the effect of a high-carbohydrate diet (hc) and a high-protein diet (hp) on the metabolism of the crayfish parastacus brasiliensis (von martens, 1869), collected in different seasons and maintained in the laboratory for 15 days. crayfish were collected monthly from january 2002 to january 2004 at s?o francisco de paula, southern brazil, in guarapirá stream. in the laboratory, the animals were kept submerged in aquariums under controlled conditions. they were fed ad libitum, for 15 days with either a hc or hp diet. at the end of this period, haemolymph samples were collected, as were hepatopancreas, gills, and abdominal muscle that were removed for determination of glycogen, free glucose, lipids, and triglycerides. the haemolymph samples were used for determination of glucose, proteins, lipids, and triglycerides. statistical analysis (anova) revealed significant seasonal differences in biochemical composition in crayfish maintained on hc or hp diets. independent of the diets offered to the animals and the controlled conditions for 15 days, the indications of seasonality were unchanged. the observed changes seemed to be related to the reproductive period. moreover, the hc diet increased all energy reserves in adult parastacids, which may aid in reproduction.
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