Relative Growth and Morphological Sexual Maturity of Macrophthalmus (Venitus) Dentipes Lucas, in Guérin-Méneville, 1836, from Two Mangrove Areas of Karachi Coast

BIHAREAN BIOLOGIST 5 (1): pp.56-62 ©Biharean Biologist, Oradea, Romania, 2011 Article No.: 111108 http://biologie-oradea.xhost.ro/BihBiol/index.html

Relative growth and morphological sexual maturity of Macrophthalmus (Venitus) dentipes Lucas, in Guérin-Méneville, 1836, from two mangrove areas of Karachi coast

Naureen Aziz QURESHI1 and Noor Us SAHER2,*

1. Department of Zoology, Government College University Faisalabad, Allama Iqbal Road, 38000 Faisalabad (NAQ). 2. Center of Excellence in Marine Biology, University of Karachi, Karachi-75270, Pakistan (NUS) * Corresponding author, N.U. Saher, Tel.: 041 9201206, Email: [email protected], [email protected]

Received: 17. October 2010 / Accepted: 17. April 2011 / Available online: 23. April 2011

Abstract. The relative growth, size at morphological sexual maturity and effect of available food and inter-specific or intra-specific competition in sentinel crabs, Macrophthalmus (Venitus) dentipes were studied. The crabs were monthly collected from two mangrove areas i.e. Sandspit and Korangi creek through transect and quadrat method. The morphometric measurements of carapace, abdomen, cheliped and male gonopod were related to carapace width as an independent variable. The growth was isometric with no significant difference in the carapace growth for male and female crabs for both sites. There was significant difference in the crab size at Korangi creek, which was smaller than Sandspit. The estimated size at onset of sexual maturity in females was greater than that of males at both study sites. In female, the abdominal width showed positive allometric growth related to reproductive advan- tages forming the incubatory chamber. The positive linear relationship of cheliped length and the gonopod for male crabs with carapace width were related to mating and other antagonistic behavioral adaptations.

Key words: Allometry, Sentinel crab, Varunidae, morphometric, interspecific competition.

Introduction Cardoso & Negreiros-Fransozo 2004, García-Dávila et al. 2005, Ibáñez-Aguirre et al. 2006), and to estimate mid-length The common sentinel crabs of genus Macrophthalmus Dema- sexual maturity (López et al. 1997, Pinheiro & Fransozo 1999, rest, 1823, usually inhabit sub tidal, inter tidal, and supra Flores et al. 2002, Colpo & Negreiros-Fransozo 2004). The tidal areas (Jones 1984, Kitaura et al. 2006). Tirmizi & Ghani size at maturity at the population level is based on 50% ma-

(1996) reported six species of the genus Macrophthalmus from turity (CW50), based on the classification of the specimens Pakistan including Macrophthalmus pectinipes; however, Ng et from a sample into mature and immature at which 50% of al. (2008) recognized this species as M. (V.) dentipes and des- the specimens are found to be mature. This methodology as- ignated Macrophthalmus pectinipes, as a junior synonym of M. sumes that maturity is attained in a narrow range of sizes (V.) dentipes. These deposit feeding sentinel crabs play a key and that there is a sigmoid type of relation between size and role in nutrient cycling and energy flow in intertidal detrital the percentage of mature animals (Roa et al. 1999, Texeira et ecosystems primarily feeding on detritus sifted from the sur- al. 2009). face sediment (Fielder & Jones 1979). They construct tempo- It was hypothesized that the relative growth of the crabs rary burrows along with surface feeding, allocleaning, fight- would vary between the two habitats varying in diversity, ing and waving around their burrows (Simons 1981, Kitaura vegetation and sediment composition. This is the first at- et al. 2006). tempt to study the relative growth of the morphometric pa- Crustaceans are particularly appropriated to studies on rameters of commonly occurring M. (V.) dentipes from the relative growth due to their hard exoskeleton that facilitates coastal mud flats of Pakistan and to characterize the degree accurate body measuring and consequent discontinuous of allometry, as well as to estimate the size at which males growth (Hartnoll 1982, Du Preez & Maclachlan 1984, Pin- and females reach morphological sexual maturity, thus evi- heiro & Fransozo 1993, Qureshi & Kazmi 1999). The growth dencing their puberty molt. The intraspecific variability of in crustaceans allows clear division of their ontogeny into size and growth has been analyzed for M. (V.) dentipes popu- different phases, and shows great differences between the lation from two sites of mangrove areas along the coast of growth rates of males and females, and of juveniles and Pakistan. adults (Hartnoll 1978). Sexual maturity in individuals can be identified from the secondary sexual characters (size of Materials and methods chelipeds, abdomen and pleopods) that show external morphological changes and differential growth rates before and Study site and Sampling methodology after the maturation life phases (Hartnoll 1978, 1982, Somer- Regular monthly samples of M. (V.) dentipes crabs were collected from the ton 1980, 1981, Vannini & Gherardi 1988, Paul & Paul 1990, mudflats of Korangi creek (24o79’N, 67o20’E) mangrove area and Sandspit (24o50’N, 66o56’E) backwater mangroves from March 2001 to February Sainte-Marie et al. 1995, Texeira et al. 2009, Saher & Qureshi 2002. Korangi creek is part of Indus Delta being the northern most creek 2011b). The relative growth patterns indicate sexual dimor- near the fishing village of Ibrahim Hyedri and has extensive mangrove phism, and can be used for predicting maturity in crabs. Al- vegetation of Avicennia marina. Similarly, the Sandspit backwaters are lometric relationship is a powerful tool for both taxonomists mangrove area (Avicennia marina) located north of the sandy coast and is and ecologists interested in intraspecific and interspecific connected to the Arabian Sea through Manora Channel (Qureshi & Sul- tana 2001). morphological variation. This kind of analyses has been used to compare intraspecific variations among populations Sampling and Laboratory analyses The crabs were collected through transect and quadrate method from from different locations (Benneti & Negreiros-Fransozo 2004, both sites. Briefly, two transects (20 meters apart) were designated in in- Relative growth of Sentinel crab 57 tertidal mangrove mudflats. On each transect, a 0.5 m quadrates frame positive allometry when b > 3, negative allometry b < 3 and isometry b = (0.25 m2) was placed (10 meters apart) at three tidal levels (low tide L1, 3 (Hartnoll 1982, Saher & Qureshi 2011b). The best fit linear regression mid tide L2, and high tide L3). The quadrate was excavated down to the equation were calculated using least square method to determine the rela- depth of 30 cm (as most of the crabs do not construct burrow deeper than tionship between morphometric variables (Hartnoll 1982, Qureshi & 30 cm), excavated mud was sieved (1 mm mesh) and the crabs were Kazmi 1999) and growth was considered isometric when 0.9 < b < 1.1 bagged in labeled polythene bags and kept on ice and brought to the labo- (Castiglioni & Negreiros-Fransozo 2004). ratory where the crabs were preserved in 70% ethanol. In the laboratory, crabs were identified, sexed, and sorted in to five categories (adult males, juvenile males, adult females, juvenile females and ovigerous females) ac- Results cording to the examination of secondary sexual characters, such as pleopod morphology, free abdomen and distinct cheliped development, and A total of 716 individuals of M. (V.) dentipes were collected the presence of eggs on the female pleopods). The size (mm) and weight (g) for each individual were noted. Following morphometric measurements during the study period, of which 219 were male (119 adults were made with a vernier caliper to the nearest 0.01 mm: carapace width and 100 juveniles) and 252 females (139 non ovigerous fe- (CW) measured at the widest part of the carapace was taken as an inde- males, 39 ovigerous and 74 juveniles) were collected from pendent variable, carapace length (CL) from the anterior median notch to Korangi creek and 115 male (66 adults and 49 juveniles) and the posterior carapace margin, cheliped propodus length (Ch.L) and 128 females (69 non ovigerous females, 28 ovigerous and 69 height (Ch.H), abdomen width (AW) of the fifth somite in female, and gonopod length (GL) (the first pair of pleopod) in male. juveniles) from Sandspit backwater. At Sandspit, the sizes of Sediment properties (percent porosity and percent organic matter the male and female crabs was significantly different (T-test, content) were analyzed at each tidal level collecting sediment samples us- p<0.05) and ranged from 3.5 to 20.0 mm and 3.5 to 17.0 mm, ing PVC cores (inner diameter (ID) 5.6 cm, up to 30 cm deep) between respectively (Table 1). The size (CW) of the male and female two transects. Percent organic matter content was determined by moni- crabs at Korangi Creek ranged from 2.0-14.5 mm and 1.75 to toring the difference of mass loss after combustion (2 - 5 g of dry sediment sample at 450 oC for 3 hrs) in a muffle furnace following Saher & Qureshi 13.5 mm, respectively (Table 1) and was not significantly dif- (2011a). ferent (t = 0.96, P = 0.34). The mean size of the male and fe-

Data analyses male crabs at Sandspit was also larger than the mean size of The relative frequency of adults (%) in each size class was plotted and fit- male and female crabs of Korangi creek (T-test, p<0.05). At ted as a sigmoid curve following the result of the logarithmic equation. Korangi Creek, the highest size class frequencies obtained for juveniles and adults were (5.5-7.0 mm) and (8.5-10.0 mm), respectively for both female and male crabs. At Sand- where, CW50 was the carapace width at which 50% of the individuals attain sexual maturity, and r was the slope of the curve. The adjusted equa- spit, the highest size class frequencies were obtained from tion was fitted by the least squares regression method (Vazzoler 1996, (5.0-7.0 mm) and (11.0-13.0 mm) for juveniles and adults re- Bertini et al. 2007, Saher & Qureshi 2011b). spectively for females (Fig. 1); and the highest size class fre- The length weight relationship was studied using the power function quencies obtained for juveniles and adults were from (7.0-9.0 y = axb (Huxley 1950) for allometry for each sex, and was linearized (logy = loga + blogx), where b indicated the slope and a, the Y-intercept, and mm) and (11.0-13.0 mm), respectively for males (Fig. 1). The

Table 1. Summary of descriptive statistics (CL=carapace length, CW=carapace width, Ab.L = Abdominal length, Ab.W = Abdominal width, Ch.L= Chela length, Ch.H =Chela height) for male and female M. (V.) dentipes collected from the Korangi creek from March 2001 to February 2002.

Site Variable SEX N Mean ± SD Min Max Korangi creek CL (mm) F 252 5.37 ± 1.75 0.75 9.0 M 219 5.48 ± 1.70 0.75 9.5 Sandspit F 129 6.90 ± 2.17 2.50 12.0 M 116 7.60 ± 2.49 3.00 13.0 Korangi creek CW (mm) F 252 7.56 ± 2.65 1.75 13.0 M 219 7.71 ± 2.50 2.00 14.5 Sandspit F 129 9.80 ± 3.19 3.50 17.0 M 116 11.2 ± 3.94 3.50 20 Korangi creek Ab.L (mm) F 252 4.77 ± 1.59 1.25 8.5 M 219 4.73 ± 1.50 1.50 8.0 Sandspit F 129 6.10 ± 2.08 2.00 11.0 M 116 6.50 ± 2.25 2.50 11.0 Korangi creek Ab.W (mm) F 252 4.71 ± 2.37 0.50 10.0 M 219 2.47 ± 0.80 0.50 4.0 Sandspit F 129 6.20 ± 3.06 0.50 12.5 M 116 3.50 ± 1.07 1.00 5.5 Korangi creek Ch. L (mm) F 252 3.58 ± 1.32 0.50 9.5 M 219 4.18 ± 1.90 1.00 12.5 Sandspit F 129 4.50 ± 1.49 1.20 8.0 M 116 6.60 ± 3.48 1.50 16.0 Korangi creek Ch. H (mm) F 252 1.59 ± 0.61 0.25 3.5 M 219 1.94 ± 0.97 0.10 5.0 Sandspit F 129 1.93 ± 0.66 0.25 3.5 M 116 3.10 ± 1.50 0.50 7.0 Korangi creek Ch. d (mm) F 252 0.93 ± 0.46 0.10 2.5 M 219 1.12 ± 0.64 0.25 4.5 Sandspit F 129 1.05 ± 0.43 0.25 2.5 M 116 1.80 ± 0.89 0.25 4.5 Korangi creek Pl. L (mm) M 219 3.47 ± 1.34 0.25 6.5 Sandspit M 116 5.10 ± 6.05 1.00 7.5

58 N.A. Qureshi & N.U. Saher

Figure 1. Size frequency distribution of female and male crabs of M. (V). dentipes at Korangi creek (KC) mangrove area and Sandspit (SST) backwater mangrove area collected during study period.

percent of organic contents of sediments at Korangi creek Relative growth of the carapace length, abdominal length (3.1 ± 1.9) were higher than at Sandspit (1.9 ± 2.9) and the and abdominal width difference was significant (P < 0.001). The linear relationship between the carapace length and carapace width showed nearly isometric growth for both Sexual maturity in male and female crab male and female crabs at both sites (Table 3). The relation- The growth curve in juveniles and adult phases were differ- ship between carapace length and abdominal length was ent at both sites (Fig. 2). The results of the logistic equation also linear and isometric for male and slightly negative for indicate that 50% male crabs were sexually mature at 10.45 females. The positive allometric growth of the abdominal mm and 6.95 mm and female crabs at 11.10 mm and 8.05 mm width was observed in the juvenile and non ovigerous adult at Sandspit and Korangi creek, respectively. Thus, the esti- females for both sites but was isometric for the male crabs mated size at onset of sexual maturity was different for (Table 3). Females showed positive allometry in the relation- males and females at each site (Fig. 2). ship AW vs. CW during both phases, indicating that the Length (CL) and weight relationships growth rate of the abdomen was greater than that of the The relative growth showed negative allometry between CL carapace width.

(carapace length) and wet weight of the body for male and Relative growth of Cheliped length, Cheliped height and female crabs at Korangi creek as compared to Sandspit Pleopod Length where the allometry was positive for male and isometric for The relative growth showed positive relationship between female (Table 2). The allometric growth showed higher value carapace width and cheliped length for juveniles and adult of the slope ‘b’ for the male crabs compared to female crabs male crabs at both sites (Table 3). However, isometric at both sites (Table 2), and there was no significant difference growth was observed for the female crabs at Sandspit (b= between the carapace length and weight relationships of 0.99) and was allometric at Korangi Creek (b=0.91) and was male and female crabs. significantly different between the sexes (P < 0.001) for

Size (CW) and weight relationships Sandspit and (P<0.001) for Korangi Creek. The growth of The relationship between wet weight and carapace width of pleopod length was positively allometric in immature crabs M. (V.) dentipes showed similar negative allometric growth as compared to mature male crabs (Table 3). for the male and female crabs at Korangi creek as with carapace length (CL); whereas at Sandspit isometric growth was observed for the female crabs and was positive for male Discussion crabs (Table 2). The value of slope ‘b’ for male crab was higher than the female crab for both sites (Table 2). Various environmental factors that typically influenced the growth in crustaceans are photoperiod, salinity, tempera-

Relative growth of Sentinel crab 59 ture, rainfall, pollution and food resource (Campbell & Ea- The strong effect of total density of co-existing crab species, gles 1983, Hines 1989, O’Connor 1990, Costa & Negreiros- either intra or interspecific competition than food availability Fransozo 1998). Considering that sentinel crabs are deposit can be also observed on size and growth of M. (V.) dentipes. feeders and feed on particulate organic matter, the organic The mean sizes of the male and female crabs were higher at content of the sediment may indicate better nutritional con- Sandspit as compared to Korangi creek with high densities ditions for these crabs. In this aspect, we expected to find of various crab species and greater number of the M. (V.) larger crabs in Korangi creek with higher organic matter dentipes (480 m-2 at Korangi creek and 199 m-2 at Sandspit) content as this site showed higher organic contents as com- were observed at Korangi creek as compared to Sandspit pared to Sandspit. However, significantly large sized crabs (Qureshi and Saher in press). At Korangi creek the M. (V.) were found at Sandspit. The supply of food in a mangrove dentipes and all the co-existing deposit feeding crab species floor for deposit feeder crabs depends on the productivity i.e., Opusia indica, Scopimera crabricauda, Ilyoplax frater and status of the area which comprise of decomposition rate of Uca sindensis (unpublished data) at Korangi creek were small leaf litter, tidal action and the sediments characteristic sized. These species of crabs extract their food in form of or- (Twilley et al. 1995, Moura et al. 1998). It shows that a simple ganic content from the surface sediment and completely or quantification of only organic matter content in the sedi- partially rely on the same food resource for their survival. ments cannot directly reflect or indicate the suitable condi- The total density, interspecific and intraspecific competition, tions for growth and reflects on the size of the population. It beside availability and the quality of the food are also the is very likely that other environmental and biotic factors af- factors that can influence the growth and the size of the fect the growth of M. (V.) dentipes at the studied sites. crabs. In Petrolisthes cinctipes, both field and laboratory stud- It is also necessary to identify different factors like inter ies showed growth rates declined with increasing conspeci- and intra specific competition for the available resources. fic density and this decline was more severe for smaller in-

Figure 2. Sigmoid curve between the carapace width (CW) and percentage of adult males and females of M. (V.) dentipes at both study sites. (SST: Sandspit, KC: Korangi creek)

Table 2. Relative growth of male and female crabs of M. (V.) dentipes based on carapace length (CL) and carapace width (CW) as independent variables and wet weight as dependant variable (+ve) positive allometry, (-ve) negative allometry and (0) isometry. (TM= total male, TF= Total female).

Site Species Sex N LogY= loga+b logX R Allometry Korangi creek CL vs Wet wt. TF 251 LogY = - 2.46 + 2.15 (logX) 0.71 -ve TM 219 LogY = - 2.63 + 2.28 (logX) 0.73 -ve Sandspi CL vs Wet wt. TF 128 LogY = - 3.18 + 3.08 (logX) 0.89 0 TM 115 LogY = - 3.19 + 3.14 (logX) 0.86 +ve Korangi creek CW vs Wet wt. TF 251 LogY= - 2.97 + 2.31 (logX) 0.84 -ve TM 219 LogY = - 3.28 + 2.63 (logX) 0.86 -ve Sandspi CW vs Wet wt. TF 128 LogY= -3.53 + 2.99 (logX) 0.88 0 TM 115 LogY= - 3.29 + 3.12 (logX) 0.86 +ve

60 N.A. Qureshi & N.U. Saher

Table 3. Relative growth of morphometric measurements in male and female crabs of M. (V.) dentipes with carapace width (CW) as independent variables (+ve) positive allometry, (-ve) negative allometry and (0) isometry. (TM=total male, TF= Total female, AM= adult male, AF= adult female, JM= Juvenile male, JF=juvenile female, OF=Ovigerous female).

Site Species Sex N LogY= loga+b logX r2 Allometry Korangi creek CL vs CW TF 251 = - 0.134 + 0.98 0.95 0 TM 219 = - 0.158 + 1.01 0.96 0 Sandspit TF 128 = - 0.085 + 0.93 0.95 0 TM 115 = - 0.011 + 0.95 0.94 0 Korangi creek CW vs Ab. L TF 251 = - 0.109 + 0.89 0.90 -ve TM 219 = - 0.134 + 0.91 0.91 0 Sandspit TF 128 = - 0.279 + 0.79 0.84 -ve TM 115 = - 0.139 + 0.91 0.93 0 Korangi creek CW vs Ab.W AF 139 = - 0.295 + 1.17 0.65 +ve JF 74 = - 0.672 + 1.59 0.75 +ve OF 39 = 0.234 + 0.62 0.69 -ve TM 219 = - 0.419 + 0.87 0.81 -ve Sandspit AF 69 = - 0.568 + 1.37 0.65 +ve JF 69 = - 0.889 + 1.67 0.79 +ve OF 28 = 0.141 + 0.77 0.76 -ve TM 115 = - 0.279 + 0.79 0.84 -ve Korangi creek CW vs Ch. L TF 251 = - 0.254 + 0.91 0.84 0 AM 119 = - 0.773 + 1.54 0.78 +ve JM 100 = - 0.336 + 1.17 0.75 +ve Sandspit TF 128 = - 0.335 + 0.99 0.92 0 AM 66 = - 0.994 + 1.69 0.86 +ve JM 49 = - 0.449 + 1.16 0.85 +ve Korangi creek CW vs Ch. H TF 251 = - 0.726 + 1.04 0.72 0 TM 350 = - 0.809 + 1.19 0.88 +ve Sandspit TF 128 = - 0.810 + 1.09 0.79 0 TM 115 = - 0.850 + 1.27 0.84 +ve Korangi creek CW vs Pl. L JM 145 = - 0.976 + 1.76 0.78 +ve AM 205 = - 0.089 + 0.74 0.65 -ve Sandspit JM 49 = - 0.776 + 1.42 0.76 +ve AM 66 = - 0.029 + 0.68 0.73 -ve

dividuals. P. cinctipes also fed less frequently at high density, Cobo (2006) and Cobo & Alves (2009) and Hartnoll (2009). and this effect was more pronounced for smaller individuals The larger size at maturity for females can be associated with (Donahue 2004). The small mean sized crab and slow growth the resource budget after puberty, which is divided between rate of M. (V.) dentipes at Korangi creek is likely to be due to the somatic growth, metabolic demand and reproductive high density of the other deposit feeding crabs at this site, cost. Ramirez Llodra (2002) stated that generally, species which minimize and limits the foraging area for these crabs. with delayed maturity live longer, allowing them to grow This indicates that intra and interspecific size-dependent in- larger and therefore have a higher fecundity while in con- teractions have effects on feeding rate and ultimately on trast earlier maturing species have a shorter generation be- growth rate as well as the average size of the individual. On cause of the shorter generation time needed to reach first re- a more general level, this study suggests that much more at- production and, the cost may be observed in a reduction in tention should be directed at available food resource for future fecundity. studying the population biology and competition between There was clear sexual dimorphism in female chelar resource consumers. growth relative to CW that showed slightly negative al- The relative growth using the morphometric data has lometric to isometric growth whereas adult males displayed been widely studied in crustaceans (Hartnoll 1982). In the positive allometric growth with cheliped length and height. present study, CL and CW both, show nearly similar slightly The strong chelar growth in brachyuran male makes the re- negative allometric relationship with wet weight. The length productive behavioral display efficient, because they use it and width of the carapace measurements characteristically to manipulate the female during mating as well, and male show isometry represented as an interval between b = 0.9 1.1 with large chelae has an advantage in partner selection espe- (Hartnoll 1978, 1982, Kuris et al. 1987, Pinheiro & Fransozo cially in semi terrestrial and terrestrial crabs, where visual 1993), however, the length weight relationship is essentially and tactile stimuli are most important for couple formation cubic and is usually represented by the power function and (Pinheiro & Fransozo 1999, Góes et al. 2000). can be linearized using log-log transformation. The carapace The positive allometric growth was observed in imma- width has been generally considered an independent vari- ture and mature females and this result agrees with Silva & able in brachyuran morphometric studies because it shows Chacur (2002) which reported the morphologic maturity size few physiological changes throughout a crab's life history of 13.3 mm CW for S. rectum and they found positive allome- (Barnes 1968). try of the abdomen width for both young and adult females. According to the result of logistic function the results Such finding indicates that morphological maturation of ab- provided the information that the size at which females at- domen might be incomplete yet when females attain the tain morphological sexual maturity was greater than that for functional maturity and, females with indeterminate growth males at both sites. The similar results were reported by may continue to enlarge the incubation space (Oh & Hartnoll

Relative growth of Sentinel crab 61

1999, Kotb & Hartnoll 2002). The ontogenic changes in the Charnov, E.L., Turner T.F., Winemiller, K.O. (2001): Reproductive constraints abdomen width of females can be related to the capacity of and the evolution of life histories with indeterminate growth. Proceedings of the National Academy of Sciences of the United States of America, female to incubate the egg mass. The developing eggs are at- Washington 98: 9460-9464. tached to the pleopods throughout incubation, with an effi- Cobo, V.J. (2006): Population biology of the spider crab, Mithraculus forceps (A. cient size and shape of the abdomen forming a cover to fa- Milne-Edwards, 1875) (Majidae, Mithracinae) on the southeastern Brazilian coast. Crustaceana 78(9): 1079–1087. cilitate fixation and to act as an incubatory chamber. The Cobo, V.J., Alves, D.F.R. (2009): Relative growth and sexual maturity of the growth of male abdomen showed negative allometry as the spider crab, Mithrax tortugae Rathbun, 1920 (Brachyura, Mithracidae) on a male abdomen only sustains and protects two pairs of pleo- continental island off the southeastern Brazilian coast. Crustaceana 82: 1265- 1273. pods that are responsible for transferring sperm during mat- Colpo, K.D., Negreiros-Fransozo, M.L. (2004): Comparison of the population ing (Pinheiro & Fransozo 1993). structure of the fiddler crab Uca vocator (Herbst, 1804) from three subtropical The relationship between CW and pleopod length (Pl. L) mangrove forests. Scientia Marina 68(1): 139-146. Costa, T.M.C., Negreiros-Fransozo, M.L. (1998): The reproductive cycle of indicated positive allometric growth during juvenile phase, Callinectes danae Smith, 1869 (Decapoda, Portunidae) in the Ubatuba region, and that changed to isometric growth with the passage to Brazil. Crustaceana 71: 615-627. the adult phase. The regression analysis of CW vs. Pl. L for Donahue, M.J. (2004): Size-dependent competition in a gregarious porcelain M. nodifrons indicated positive allometric growth during the crab Petrolisthes cinctipes (Anomura: Porcellanidae). Marine Ecological Progress Series 267: 219–231. juvenile phase and with passage to the adult phase, growth Du Preez, H.H., Mclachlan, A. (1984): Biology of three-spot swimming crab was negative. This result is also similar to the observation Ovalipes punctatus (De Hann). III. Reproduction, fecundity and egg made by Guimaraes & Negreiros-Fransozo (2002) that gono- development. Crustaceana 47: 285-297. Fielder, D.R., Jones, M.B. (1979): Observations of feeding behaviour in two New pod growth in Eurytium limosum passed from positively al- Zealand mud crabs (Helice crassa and Macrophthalmus hirtipes ). Mauriora 6: lometric in the juvenile phase, to negative allometric growth 41-46. in the adults. These results are comparable with other stud- Flores, A.V.V., Paula, J. (2002): Sexual maturity, larval release and reproductive output of two brachyuran crabs from a rocky intertidal area in central ies and this differential growth has been related to the ability Portugal. Invertebrate Reproduction and Development 41: 21-34. of wide size range of males to copulate successfully with Garcia-Dávila, C.R., Magalhães, C., Guerrero, J.C.H. (2005): Morphometric wide range of females improving their reproductive output variability in populations of Palaemonetes spp. (Crustacea, Decapoda, Palaemonidae) from the Peruvian and Brazilian Amazon Basin. Iheringia, (Hartnoll 1974, Bertini et al. 2007, Saher & Qureshi 2011b). serie Zoologia 95(3): 327-334. In conclusion, these results show the significant effect of Góes, P., Sampaio, F.D.F., Carmo, T.M.S., Toso, G.C., Leal, M.S. (2000): crab density on the size and growth rate of the M. 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