scholarly journals Studies on the allometric growth of the caramote prawn Melicertus kerathurus (Decapoda, Penaeidae) in Western Greece (E. Mediterranean)

2009 ◽  
Vol 10 (1) ◽  
pp. 25 ◽  
Author(s):  
K. KAPIRIS ◽  
E. KALLIAS ◽  
A. CONIDES

The relative growth of eleven body parts (carapace length, height, width, abdominal length, height and width, rostral length and telson length) of males and females of the caramote prawn Melicertus kerathurus was studied in samples from the Amvrakikos Gulf (Western Greece, E. Mediterranean). In addition to this, the relative growth of the length and the maximum width – and consequently the surface - of the appendix masculina of males was also studied. In general, both sexes showed similar patterns of relative growth. However, the females’ body appendages were significantly greater than those of the males. A negative allometry of escaping appendages (telson), abdomen (related to the metabolic processes, rapid locomotion and reproduction), rostrum, appendix masculina (related to mating and sperm transfer) and carapace height and width was found in both sexes. The biometric studies in this species in the central and western Mediterranean are in agreement with those from the eastern part of the basin, suggesting that all the populations throughout the Mediterranean could be considered as uniform.

Crustaceana ◽  
2014 ◽  
Vol 87 (13) ◽  
pp. 1567-1577 ◽  
Author(s):  
F. Ahamed ◽  
F. Ahamed ◽  
J. Ohtomi

The pandalid shrimp Plesionika izumiae Omori, 1971 is widely distributed in the west Pacific region. This is a relatively common shrimp in the coastal waters of Japan, except off northern Honshu and Hokkaido, and it is commercially important for small-scale bottom seine fishery. The relative growth of secondary sexual characters (appendix masculina for the male and abdomen width for the female) of P. izumiae was studied in Kagoshima Bay, southern Japan, from December 2009 to November 2011. The length of the appendix masculina was measured for males, while abdomen width near the second pleopod was measured for females. The relationships between carapace length and the observed secondary sexual characters were studied using the least squares method. The appendix masculina showed positive allometric growth in relation to carapace length (CL), showing discontinuities at 7.3 mm CL. The width of the female abdomen showed positive allometric growth with CL, while indicating a discontinuity at 8.6 mm carapace length. The observed discontinuities in the growth rate of secondary sexual characters of P. izumiae might be attributed to sexual maturation.


1974 ◽  
Vol 22 (3) ◽  
pp. 417 ◽  
Author(s):  
NA Campbell ◽  
RJ Mahon

A multivariate approach has been used to study morphological variation in the blue and orange-form species of rock crab of the genus Leptograpsus. Objective criteria for the identification of the two species are established, based on the following characters: width of the frontal region of the carapace; width of the posterior region of the carapace (rear width); length of the carapace along the midline; maximum width of the carapace; and the depth of the body. The first canonical variate, which differentiates between the two species, represents a contrast between the carapace width relative to the width of the front lip and the depth of the body; the blue-form species has a greater relative carapace width than has the orange form. The second canonical variate, which presents a contrast between the rear width and the carapace length, identifies males and females within each species; males have a greater relative carapace length than have females. All individuals, including 20 not used in the study, were correctly identified for colour form. The clear separation of the blue and orange forms achieved by canonical analysis supports the previously determined specific status of the two forms.


2017 ◽  
Vol 65 (2) ◽  
pp. 97 ◽  
Author(s):  
Glenn P. Edwards ◽  
Grahame J. Webb ◽  
S. Charlie Manolis ◽  
Alex Mazanov

We conducted a morphometric analysis of 279 Crocodylus johnstoni, using specimens from the McKinlay River (n = 265) and Arnhem Land (n = 14), to meet the management need for predicting body size of C. johnstoni from isolated body parts. The results also allow reconstruction of C. johnstoni dimensions for comparison with other crocodilian species. We detected sexual dimorphism in some body measurements from the McKinlay River, and geographic variation in the morphology of McKinlay River and Arnhem Land populations, but differences were slight. There is pronounced allometric growth in C. johnstoni in the immediate post-hatching phase, largely due to elongation of the snout after exiting the confines of the egg. We compared the size, shape and relative growth of C. johnstoni with that of other crocodilian species for which equivalent data are available, but particularly the other Australian crocodile, Crocodylus porosus. C. porosus has a proportionately longer tail and a shorter but wider snout than C. johnstoni, and we discuss possible ecological correlates of these and other differences.


2013 ◽  
Vol 14 (1&2) ◽  
pp. 55-59
Author(s):  
Shurveer Singh ◽  
Ashish K. Chowdhary ◽  
Anita Rawat Rana ◽  
S.N. Bahuguna

The present study was carried out on freshwater crab in hillstream Khoh of district Pauri Garhwal in Uttarakhand state. Samples of crab were collected from the population inhabits the hillstream Khoh on monthly basis during May 2011 to April 2012. The regression equations for the length-weight relationship in crabs were obtained as Y=2.045X+0.266 and Y=1.522X+0.392 for males and females respectively. The ANOVA test revealed significant differences in carapace length-weight relationship at p<0.05 for both the sexes. Allometric growth pattern was observed in the study for both sexes of P. koolooense. A weak relationship was observed between length and weight of the specimen.


2019 ◽  
Vol 109 ◽  
Author(s):  
Caio dos Santos Nogueira ◽  
Marcela Silvano de Oliveira ◽  
Giuliano Buzá Jacobucci ◽  
Ariádine Cristine de Almeida

ABSTRACT The main objective of this study was to estimate the morphological sexual maturity of Macrobrachium brasiliense (Heller, 1862) and to analyze the relative growth of the species. During one year of sampling, from July 2012 to June 2013, 199 specimens were collected in a stream located in a Cerrado biome, in the Triângulo Mineiro region, state of Minas Gerais. Once identified and sexed, the length of the carapace, the length of the segments of the chelipeds (ischium, merus, carpus, propodus and dactyl) and width of the pleura were measured (mm). The maximum and mean sizes of the carapace length measured 20.5 mm (Mean: 9.6 ± 4.2 mm) and 20.1 mm (Mean: 7.7 ± 3.4 mm) for males and females, respectively. The propodus length for males, and the pleura width for females, were used for the classification of the specimens into juvenile and adult, using K-means analysis and discriminant analysis. The relative growth of the species was also evaluated through covariance analysis for all structures (ANCOVA, α = 0.05). In females, the growth of most structures occurred equally between juveniles and adults, with the exception of the merus and pleura structures. On the other hand, the growth of almost all structures of males differed between juveniles and adults. Only the carpus and the pleura growth were similar. We also estimated the size at onset of morphological sexual maturity at 8.64 mm CL for males (CL50% r = 1.71) and 8.03 mm CL for females (CL50% r = 0.07). Our results contribute to the understanding of some important questions related to the reproductive biology of M. brasiliense. We noted that males grow differently from females and become the largest individuals in the population, resulting in a sexual dimorphism. Such sexual dimorphism might promote the development of the temporary mating guarding behavior, a reproductive strategy very important for caridean shrimps.


Author(s):  
Marina Machado da Costa ◽  
Patrícia Hoffmann ◽  
Geslaine Rafaela Lemos Gonçalves ◽  
Maria Lucia Negreiros-Fransozo

The shrimp Potimirim brasiliana plays an important role in streams along the Brazilian coast as it feeds on the organic debris from the surrounding ecosystem. We determined the morphological sexual maturity of P. brasiliana by means of relative growth. Monthly throughout a year, we used sieves (2 mm mesh diameter) to collect the specimens in a coastal stream. A total of 3,521 specimens had their carapace length (CL) measured, as well as their second pleura length (PL) and the length (AML) and width (AMW) of the appendix masculina. The studied relationships were the following: CL vs. PL; CL vs. AML and CL vs. AMW, with the data adjusted to a logistic equation. All the relationships tested among the demographic groups differed statistically. The CL50 of females measured 3.45 mm, while the CL50 of males measured 2.75 mm. Two adult morphological groups were set apart for each sex. The CL vs. AMW relationship is the best at demonstrating the separation of the morphological groups for males. This fact is an intriguint issue as it suggests the presence of morphotypes in males, probably, playing different roles in the reproductive process.


2017 ◽  
Vol 9 (3) ◽  
pp. 338-343 ◽  
Author(s):  
Sarvabhowma Chakravarty MYLA ◽  
Vijaya Bharathi TIRUMANI ◽  
Rama Chandra Ganesh PATURI

The relationship of length-weight and width-weight of the carapace and the relative condition factor of mud crab Scylla serrata from Coringa Wildlife Sanctuary (Andhra Pradesh, India) was the subject of present study. Significant difference in both males and females was observed between carapace length-weight, carapace width-weight with a linear relationship. The regression values of both the sexes were found to be statistically significant. The regression equations calculated for length-weight were W= 0.00000178 L 3.1139 (r= 0.95) for males, W= 0.00000520 L 2.8056 (r=0.94) for females and for sexes combined it was W = 0.0000297 L 2.9891(r= 0.94).  In case of carapace width-weight relationship of males, females and sexes combined the regression equations were W= 0.00000121 CW 3.0426 (r= 0.92), W= 0.00000178 CW 2.775 (r=0.93) and W = 0.00000204 CW 2.9210(r= 0.92) respectively. The male crabs showed positive allometric growth whereas female had negative allometric growth. Analysis of covariance confirmed remarkable difference between males and females in the growth pattern. The mean relative condition factor (Kn values) of both males and females and of the pooled sexes ranged from 0.680 (April) to 1.029 (November). A gradual raise in Kn values was observed from small- to big- sized crabs in both the sexes. Peak values were observed in 12.0-13.9 cm size group in November.


2018 ◽  
Vol 26 (4) ◽  
pp. 223-230
Author(s):  
Yulianus Sedik ◽  
Dominggus Rumahlatu ◽  
Bambang Irawan ◽  
Agoes Soegianto

Abstract The objectives of this study were to determine the length-weight relationships (LWRs), chelae length (ChL)-width (ChW) relationships, carapace length (CL)-width (CW) relationships, sexual dimorphism, and condition factor (K) of Cherax gherardiae from Maybrat, West Papua Indonesia. The sex ratio of C. gherardiae was found to be 1.04:1. The LWRs for males, females, and all individuals were W = 0.225L1.96, W = 0.181L2.02, and W = 0.187L2.03, respectively. Males and females exhibited negative allometric growth (b<3). There was no significant difference in lengths between males and females; however, the weight of males was greater than that of females. The K values for males, females, and all individuals were 3.17, 3.09, and 3.13, respectively. The ChL of the crayfish ranged from 1.0 to 7.5 cm, and the ChW ranged from 0.4 to 2.5 cm. The CL of crayfish ranged from 1.6 to 6.0 cm, and the CW ranged from 0.6 to 4.1 cm. Males had longer chelae and carapaces than did females. There was no significant difference in chelae width or carapace width between males and females. The ChL-ChW relationships for males, females, and all individuals were ChW = 0.312ChL + 0.260, ChW = 0.397ChL - 0.050, and ChW = 0.345ChL + 0.119, respectively. The CL-CW relationships for males, females, and all individuals were CW = 0.750CL-0.955, CW = 0.526CL - 0.178, and CW = 0.635CL-0.543, respectively.


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.


2007 ◽  
Vol 97 (3) ◽  
pp. 268-272 ◽  
Author(s):  
Rafael Augusto Gregati ◽  
Maria Lucia Negreiros-Fransozo

The relative growth and morphological sexual maturity of Chasmagnathus granulatus Dana, 1851 are presented for the first time to a mangrove population. The crabs were obtained during low tide periods, in the mangrove of Jabaquara Beach, Paraty, Rio de Janeiro, Brazil. All crabs in intermolt stage were sexed and had their body parts measured as follows: body height (BH), carapace length (CL) and width (CW), major cheliped propodus height (PH) and length (PL) for each sex, gonopod length (GL) and abdomen width (AW) for males and females, respectively. The relative growth was described using the allometric equation y=ax b and the size at onset sexual maturity was achieved using the software Mature I. The size of specimens ranged from 4.1 mm to 39.5 mm CW. The growth pattern was different between sexes in the cheliped relationships; the relationships BH vs. CW evidenced positive allometry for juveniles; PL vs. CW and PH vs. CW positive allometry for most crabs except juvenile females; AW vs. CW and GL vs. CW evidenced positive allometry for juveniles and isometry for adults. The relationships that best indicated the change from the juvenile to the adult phase were PH vs. CW for males and AW vs. CW for females. The size in which 50% of males from this population are mature is at 19.7 mm of CW (F=144.14; p<0.05) and for females it is at 19.2 mm of CW (F=166.54; p<0.05). The sizes obtained in this mangrove population are larger than those from previous studies, that could be attributed to a species plasticity concerning the habitat structure.


Sign in / Sign up

Export Citation Format

Share Document