scholarly journals Relative growth of Acantholobulus schmitti (Rathbun, 1930) (Crustacea, Brachyura, Panopeidae) at Guaratuba Bay, southern Brazil

2013 ◽  
Vol 73 (4) ◽  
pp. 863-870 ◽  
Author(s):  
SF Frigotto ◽  
MZ Marochi ◽  
S Masunari

A study on the relative growth of the crab Acantholobulus schmitti (Rathbun, 1930) (Decapoda, Brachyura, Panopeidae) was performed with allometric techniques. The species is associated with lanterns used for oyster farming at Guaratuba Bay, southern Brazil. Crabs were obtained from five lanterns from March through December 2009. The following morphological characteristics were measured: the carapace width (CW), the height and length of the major cheliped propodus (LPH and LPL), the width of the female abdomen at the base of the 4th somite (AW) and the length of the male gonopod (GL). A total of 1,004 individuals of A. schmitti were measured, of which 451 were males, 323 non-ovigerous females and 230 ovigerous females. The CW of the males varied from 1.87 to 11.86 mm, that of non-ovigerous females from 1.44 to 8.77 mm and that of ovigerous females from 4.09 to 11.12 mm. The plot of LPH against CW showed a mean inflection point at 3.67 mm CW for the males. This result indicated that male crabs are juvenile below this value and adult above it. For the females, the corresponding inflection point occurred at 3.36 mm CW in the plot of AW against CW. These results, CW x LPH and CW x AW, highlight the importance of chelae enlargement at the onset of maturation in males. Similarly, the widening of the abdomen in females is required to accommodate egg clutches during the reproductive period. Heterochely was recorded in both sexes. Right-handed crabs were more frequent than left-handed ones, with percentages of 75.8% in males and 82.7% in females. The population of A. schmitti from Guaratuba Bay becomes sexually mature at an earlier age than A. schmitti from the coast of São Paulo state. The lanterns used in oyster farming furnish a safe habitat in which these crabs can spend their entire benthic life.

Author(s):  
A. D. Kassuga ◽  
A. Marafon-Almeida ◽  
S. Masunari

An analysis of the population structure of the tanaid Sinelobus cf. stanfordi was performed at Pinheiros River mangrove, Guaratuba Bay, Paraná State, southern Brazil (25°49′S 48°34′W). Fifteen samples of 12 × 12 cm were obtained bimonthly from the surface of galleries (interconnected burrow complex) constructed by the adult mangrove crab Ucides cordatus from June 2007 to April 2008. The carapace length (CL) of a total of 714 tanaids was measured. Tanaids were divided into four demographic categories: males (M), ovigerous females (OV), preparatory females (PREP) and non-reproductive individuals (NREP) with a mean CL of 0.55, 0.49, 0.48 and 0.43 mm, respectively. In the NREP group, specimens smaller than 0.32 mm were classified as juveniles. NREP predominated in all sampling months, and among sexually mature individuals, a strong predominance of females was observed throughout the study period. Temporal fluctuations in abundance were observed, with a peak in August 2007. The reproductive period of this species is continuous, with a peak in the summer, like most S. cf. stanfordi populations.


2017 ◽  
Vol 65 (3) ◽  
pp. 373-381 ◽  
Author(s):  
Setuko Masunari ◽  
Salise Brandt Martins ◽  
Murilo Zanetti Marochi ◽  
Wilson Sebastián Serra ◽  
Fabrizio Scarabino

Abstract A comparative study on size and shape of Leptuca uruguayensis was carried out between populations from Garças River, Brazil (BP), and Solís Grande River, Uruguay (UP). The size of the onset of sexual maturity was also estimated for UP. A total of 36 crabs BP and 387 crabs UP were analyzed. In the relative growth analysis, carapace width (CW) for both sexes, major cheliped length (LMC) for males and abdomen width (AW) for females were measured. The centroid size of carapace (1.40±0.19 cm BP and 1.88±0.30 cm UP) and cheliped (1.16±0.22 cm BP and 1.58±0.45 cm UP) differed significantly (p<0.001). The shape also differed significantly (p<0.001), having UP wider carapace than BP, rostrum projected forward and posterior margin positioned more anteriorly; the cheliped of UP was also wider than BP. In UP, males' CW ranged 4.28-19.5 mm and females' 2.53-16.3 mm CW; males' LMC ranged 1.79-31.60 mm and females' AW, 0.80-8.53 mm. The onset of sexual maturity of UP was estimated in 12.20 mm CW for males and 7.81 mm for females. These differences are likely related to abiotic variables acting distinctly in the two localities.


2009 ◽  
Vol 99 (1) ◽  
pp. 82-91 ◽  
Author(s):  
Fabíola M. Rezende-Pinto ◽  
Laura Verrastro ◽  
Juliana C. Zanotelli ◽  
Paulo C. R. Barata

The reproductive cycle and sexual dimorphism of the lizard Cnemidophorus vacariensis Feltrim & Lema, 2000 were studied on the basis of data gathered between August 2004 and August 2006 in Vacaria, Rio Grande do Sul, Brazil. Snout-vent length (SVL) of sexually mature males varied between 48.8 and 72.9 mm (x = 63.3 ± 6.0 mm; n = 76) and, for females, between 57.4 and 81.8 mm (x = 70.0 ± 5.9 mm; n = 73). Other morphological characteristics were also compared between sexes. Reproduction was seasonal, and observations indicate two clutches in the same reproductive season. Clutch size and other reproductive characteristics were analyzed as well as the relation between reproduction and environmental factors. Cnemidophorus vacariensis is apparently endemic to highland plateaus in southern Brazil and has been classified as vulnerable on some lists of threatened fauna in this country. Some suggestions for conservation measures are presented, due to the observed degradation of this species' environment.


Crustaceana ◽  
2011 ◽  
Vol 84 (8) ◽  
pp. 897-904
Author(s):  
Sung Il Lee ◽  
Jung Nyun Kim ◽  
Hyun-Woo Kim ◽  
Chul-Woong Oh ◽  
Jong-Hun Na

AbstractSnow crabs, Chionoecetes spp., are among the commercially most important species of Decapoda in the world, and proper stock assessment and management are required for their sustainable use. In the present study, morphological characteristics of three snow crabs, Chionoecetes japonicus, Chionoecetes opilio and a hybrid form exhibiting characteristics intermediate between those of the parent species, Chionoecetes japonicus/opilio, have been compared. The ratio of carapace length including rostral horn (CL(RL)) to carapace width (CW) in C. japonicus, C. opilio, and the C. japonicus/opilio hybrid was 0.973 ± 0.020, 0.983 ± 0.019, and 0.956 ± 0.019, respectively. The only significant difference in regression slope among the three crabs, was between CW and chela height (CH), indicating that at a given size, the hybrid form is the fastest in the growth of chela height in relation to carapace width. In C. japonicus and C. opilio, the relationship between CW and total weight (TW) was significantly negatively allometric, while in the hybrids, it was significantly positively allometric. This indicates that at a given size, the hybrid form is heavier than the others.


2012 ◽  
Vol 12 (4) ◽  
pp. 62-67 ◽  
Author(s):  
Marcelo Oscar Bordignon ◽  
Adriana de Oliveira França

The reproductive pattern of the greater bulldog bat (Noctilio leporinus) was studied in southern Brazil from January to December 1999. The morphological characteristics of their reproductive organs were recorded monthly, through histological analysis of testes and ovaries. Those data were correlated with forearm size and body mass, as well as with external reproductive characteristics. The diameter of the seminiferous tubule increased proportionately to testis mass and body weight, and larger males had greater testis mass. Sexually mature males were recorded throughout the year. Ovary histology revealed that females ovulate between July and December. Lactating females were recorded in nearly every month of the year. Noctilio leporinus has a bimodal polyestrous pattern, with an increase in the recruitment of juveniles between January and May.


Crustaceana ◽  
2011 ◽  
Vol 84 (10) ◽  
pp. 1221-1241 ◽  

AbstractThe study of relative growth was used to determine the dimensions that best demonstrate the morphological sexual maturity of Ucides cordatus from two mangrove areas (Ariquindá and Mamucabas) of the southern coast of the state of Pernambuco, northeast Brazil. The crabs were collected manually, with a capture effort by one person, during low tide in three different areas (each 25 m2) during a period of one year from April 2008 to March 2009. Crabs of both sexes were measured for the following dimensions: carapace width (CW); carapace length (CL); major cheliped propodus length (CPL); major cheliped propodus height (CPH); abdomen width (AW) and gonopod length (GL). These variables were subjected to an analysis of K-means clustering followed by a bivariate discriminant analysis, which separated the data into two groups: juveniles and adults. After separation of the groups, each age category was grouped into sixteen size classes of CW and the proportion of adults in each size class was calculated, and fitted to a logistic equation. Subsequently, an interpolation was performed to determine the size at which 50% of the males and females were mature. The relationships that best demonstrated the size at maturity were CPL vs. CW for males (Positive allometry; Ariquindá — juveniles b = 1.27, adults b = 1.41; Mamucabas — juveniles b =1.27, adults b = 1.44) and AW vs. CW for females (Positive allometry; Ariquindá — juveniles b = 1.34, adults b = 1.28; Mamucabas — juveniles b = 1.32, adults b = 1.44). The present analysis indicates that, for these same relationships, 50% of males and females are morphologically mature, at, respectively, 38.0 and 35.4 mm CW in Ariquindá, and 37.3 and 32.9 mm CW in Mamucabas. Positive allometry shown in the female abdomen is related to egg incubation, and the excessive growth observed in the male cheliped must be related to reproductive behaviour, including courtship and intra- or inter-specific agonistic interactions with other males.


2004 ◽  
Vol 21 (1) ◽  
pp. 137-144 ◽  
Author(s):  
Daniela da Silva Castiglioni ◽  
Maria Lucia Negreiros-Fransozo

A study on the relative growth of two populations of Uca rapax (Smith, 1870) was performed primarily to determine the size at onset sexual maturity. The species was sampled monthly in Itamambuca (23º24'43"S and 45º00'73"W) and Ubatumirim (23º20'17.8"S and 44º53'2.2"W) mangroves. Carapace width (CW) and length (CL), abdomen width (AW), major cheliped propodus length (PL) and height (PH) for each sex, and gonopod length (GL) for males were measured with a calliper (0.01 mm). Allometric analyses were used to estimate size at maturity. The relationships that most precisely indicated the size at onset of sexual maturity were AW vs. CW, for females and PL vs. CW, for males. Males and females are mature, respectively at 15.2 and 12.1 mm CW in samples from Itamambuca and 13.5 and 11.2 mm CW in samples from Ubatumirim mangrove. Positive allometric growth of females abdominal width is likely related to the incubation process, while positively allometry growth of male's cheliped almost certainly relates to reproductive behaviour.


Author(s):  
Bruno Gabriel Nunes Pralon ◽  
Maria Lucia Negreiros-Fransozo

The relative growth of the fiddler crab Uca cumulanta was studied, primarily to determine the size at the onset of sexual maturity for a mangrove population in the estuary of the Patitiba River, Paraty, Rio de Janeiro state, Brazil. The evaluation of the morphological sexual maturity of U. cumulanta was performed using the allometric technique. The relationships that most precisely indicated the size at onset of sexual maturity were carapace length (CL) vs propodus length for males and CL vs abdomen width for females. Males and females are mature at 5.25 and 4.75 mm CL, respectively. The remarkable ontogenetic changes observed in the allometric growth of the male major cheliped and the female abdomen, indicate that growth of these structures is closely connected to the timing of sexual maturity. The relative size at onset maturity obtained for this species was 0.68 and this index was compared to that seen in other species in the genus.


Phytotaxa ◽  
2021 ◽  
Vol 521 (3) ◽  
pp. 177-192
Author(s):  
JORDANO D. TAVARES DE CARVALHO ◽  
CATARINE MARKUS ◽  
ALDO MEROTTO JUNIOR ◽  
RENATO A. ZÁCHIA ◽  
MARILIA SCHUCH ◽  
...  

Prosopanche cocuccii is described as a new species from Southern Brazil. It resembles P. bonacinae due to the trigonous rhizome and by the general size of the flower organs. Nevertheless, P. cocuccii is distinguished by the main floral morphological characteristics used to differentiate species. In addition, the new species presents some rare characters for the genus, such as a highly branched rhizome and flowers usually grouped in fascicles. We provide a description, illustrations, field photographs, morphological details under the stereomicroscope, and comments on habitat, ecology, distribution, and conservation of the new species, as well as an updated key for the genus Prosopanche. In addition, we identified that P. cocuccii produces a large number of rhizomes and fruits for each single host specimen of tobacco (Nicotiana tabacum), which resulted in a decrease in height and growth of its only known host plant.


2007 ◽  
Vol 50 (2) ◽  
pp. 259-267 ◽  
Author(s):  
Giovana Bertini ◽  
Adriane Araújo Braga ◽  
Adilson Fransozo ◽  
Michéle de Oliveira Dias Alves Corrêa ◽  
Fulvio Aurélio de Morais Freire

The relative growth and size at onset of morphological sexual maturity of the stone crab Menippe nodifrons were investigated. A total of 399 crabs was captured on Praia Grande and Tenório beaches at Ubatuba. Carapace width (CW) and length, cheliped propodus length and height, abdomen width in females, and gonopod length in males were recorded. In females, the abdominal width showed negative allometry for juveniles and positive allometry for adults; the puberty molt occurred at 31.6 mm CW. In males, the size at onset of morphological sexual maturity was estimated as 29.7 mm CW; the gonopod growth showed positive allometry for juveniles, and an isometric relationship for adults. The gonopod length and the abdominal width were the most appropriate morphometric variables to estimate size at onset of sexual maturity in this stone crab.


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