Abdomen Width Research Articles

Quality control of Cotesia flavipes (Cameron) (Hymenoptera: Braconidae) from different Brazilian bio-factories

The goal of this study was to evaluate the quality of Cotesia flavipes from different bio-factories as biological control agents. We evaluated biological characteristics of the parasitoids throughout their lifespan, and measured the body length and width, abdomen width, thorax width and width and length of the right forewing of female and male parasitoids. Our results showed that the number of males and pupal viability were similar among the bio-factories; the number of emerged females was greater in bio-factories I and II; the egg-pupa period and the pupal period were shorter in bio-factory IV; and a greater longevity was found in bio-factories II and III. Sex ratio (at approximately 60% females) was satisfactory (in terms of suitability for release) across all bio-factories. For morphometric measurements, the body, abdomen and wing widths were similar in males; however, thorax width was greater in the males from bio-factory I; bio-factory III produced females with the highest body length; bio-factory I produced females with the greatest abdomen width; bio-factories III and IV produced females with the greatest wing length. Among the bio-factories studied, bio-factory IV produced the best quality C. flavipes, with respect to the greatest number of parasitoids per pupal mass (a mean of 57% more parasitoids) in a satisfactory sex ratio, and with the shortest developmental time, which facilitates faster rearing in the laboratory. Studies such as this, which assess the quality of a mass-produced C. flavipes, are crucial for the continued use of this parasitoid in controlling Diatraea saccharalis in the field.

Predicting carcass and body fat composition using biometric measurements of grazing beef cattle1

This study was conducted to develop equations to predict carcass and body fat compositions using biometric measures (BM) and body postmortem measurements and to determine the relationships between BM and carcass fat and empty body fat compositions of 44 crossbred bulls under tropical grazing conditions. The bulls were serially slaughtered in 4 groups at approximately 0 d (n = 4), 84 d (n = 4), 168 d (n = 8), 235 d (n = 8), and 310 d (n = 20) of growth. The day before each slaughter, bulls were weighed, and BM were taken, including hook bone width, pin bone width, abdomen width, body length, rump height, height at withers, pelvic girdle length, rib depth, girth circumference, rump depth, body diagonal length, and thorax width. Others measurements included were total body surface (TBS), body volume (BV), subcutaneous fat (SF), internal fat (InF), intermuscular fat, carcass physical fat (CFp), empty body physical fat (EBFp), carcass chemical fat (CFch), empty body chemical fat (EBFch), fat thickness in the 12th rib (FT), and 9th- to 11th-rib section fat (HHF). The stepwise procedure was used to select the variables included in the model. The r(2) and the root-mean-square error (RMSE) were used to account for precision and variability. Our results indicated that lower rates of fat deposition can be attributed to young cattle and low concentration of dietary energy under grazing conditions. The BM improved estimates of TBS (r(2) = 0.999) and BV (r(2) = 0.997). The adequacy evaluation of the models developed to predict TBS and BV using theoretical equations indicated precision, but lower and intermediate accuracy (bias correction = 0.138 and 0.79), respectively, were observed. The data indicated that BM in association with shrunk BW (SBW) were precise in accounting for variability of SF (r(2) = 0.967 and RMSE = 0.94 kg), InF (r(2) = 0.984 and RMSE = 1.26 kg), CFp (r(2) = 0.981 and RMSE = 2.98 kg), EBFp (r(2) = 0.985 and RMSE = 3.99 kg), CFch (r(2) = 0.940 and RMSE = 2.34 kg), and EBFch (r(2) = 0.934 and RMSE = 3.91 kg). Results also suggested that approximately 70% of body fat was deposited as CFp and 30% as InF. Furthermore, the development of an equation using HHF as a predictor, in combination with SBW, was a better predictor of CFp and EBFp than using HHF by itself. We concluded that the prediction of physical and chemical CF and EBF composition of grazing cattle can be improved using BM as a predictor.

Some Morphological Characteristics of Kangal Dogs Raised in Various Parts of Turkey. I. Body Measurements

In this PhD Thesis, data of some morphological characteristics of Kangal Dogs raised in various parts of Turkey were analyzed. Data collected from 432 male and 303 female, total 735 dogs were examined at 3 different groups as sheep breeders, civil and official dog breeding farms. Collected data were analyzed for sex, coat colour, style of breeding, national and local regions using methods of ANOVA and Duncan. Means of adult weight, withers height, height at rump, body length, heart girth circumference, cannon circumference, ear length, head length, muzzle length, head circumference, limb length, tail length, head width, chest width, abdomen width, chest depth, haunch width at Kangal Dogs were found as 45.9 kg; 74.8, 73.8, 84.5, 86.2, 13.2, 13.5, 30.7, 12.6, 53.8, 35.6, 47.8, 14.3, 19.7, 15.9, 31.6, 22.7 cm respectively. It could be concluded that the real examples of Turkish Kangal Shepherd Dogs could be found in a place where dogs raised by sheep breeders rather than raised at official or civil breeding farms.

Reproductive aspects and adaptive relative growth of the tropical crab Goniopsis cruentata

The knowledge of reproductive traits is essential to the comprehension of the evolution of life history and population dynamics of a species. Here, we evaluate morphological maturity, relative growth, fecundity, relationship between size and fecundity, brood loss, and seasonal variation of brood size in the crab Goniopsis cruentata. Crabs were collected during a period of one year in a tropical mangrove, Northeast Brazil. Males matured at smaller sizes than females. Compared to other studies, this result indicates that there appears to be no pattern of sexual maturity between the sexes in this species, with both sexes maturing earlier or later. The relative growth of the gonopod length (males) and abdomen width and length (males and females) is clearly related to different sex roles, i.e., incubating eggs in females and maximizing the number of mates in males. Fecundity increased with female size and was similar to the fecundity of previous studies with the same species. Egg number of females incubating early-stage eggs was higher than those incubating late-stage eggs, indicating loss of eggs during embryogenesis. Fecundity of females occurring in the dry season was higher than that of females occurring in the rainy season, indicating seasonal variation of brood size.

Quality of Cotesia flavipes (Hymenoptera: Braconidae) reared at different host densities and the estimated cost of its commercial production

The objective of this study was to evaluate the quality of the parasitoid Cotesia flavipes (Cameron) reared at different densities of its host, Diatraea saccharalis (Fabr.), and to estimate the costs of its production. After parasitism, we placed hosts in petri dishes at densities of three, four or five larvae per dish and evaluated the biological characteristics of the parasitoids throughout their lifespan. We measured the body length, body width, abdomen width, thorax width, and width and length of the right forewing of female and male parasitoids. We discovered that host density affected the parasitoid sex ratio. The different host densities per dish resulted in a similar lifespan. A host density of three larvae per dish resulted in a better sex ratio. Parasitoids reared at different host densities per dish had similar body lengths. Therefore, a density of 5 D. saccharalis larvae per dish is suitable for mass rearing of C. flavipes. At this host density, the cost associated with rearing C. flavipes is USD 0.05 per pupal mass.

Allometric growth of two species of Ephemeroptera from Neotropical mountains streams

The present study evaluated the relative growth and allometry of Massartella brieni Lestage and Thraulodes sp. (Leptophlebiidae: Ephemeroptera). The morphometric analysis was based on 23 measurements and was conducted using a multivariate approach. Throughout postembryonic ontogeny, all of the head measurements, including those of the mouthparts, exhibited negative allometric growth. The mesothorax and wing pad exhibited positive allometric growth. The hind legs lengths in M. brieni and the fore and hind legs lengths in Thraulodes sp. exhibited positive allometry. The abdominal length in these two species exhibited positive allometric growth. Positive allometry was also observed along the abdomen width for M. brieni, and isometry was observed for Thraulodes sp. The relative strengthening of the thorax (in preparation for the winged stage) and the relative increase in the abdomen (which may be related to the development of the reproductive structures) during growth indicate that many of the structures that exhibit positive allometric growth are related to the transition from the aquatic to the adult stage of development.

Reproductive biology of the spider crab Leucippa pentagona (Decapoda: Epialtidae), in Bustamante Bay, Argentina

Sizes at maturity, breeding period, and fecundity of the spider crab Leucippa pentagona in Bustamante Bay, Argentina (45.11oS, 66.56oW) were analyzed. Specimens were collected monthly between May 2006 and February 2008. The size at morphometric maturity was determined based on relative changes in cheliped length for males and abdomen width for females. The presence of spermatophores in the male deferent ducts and of eggs in the female abdomens were the criteria used to determine physiological maturity. The temporal variation of the proportion of ovigerous females was analyzed. Oocyte sizes in ovigerous females were measured to evaluate the occurrence of multiple spawnings. In males, the sizes at morphometric and physiological maturity were 28.05 and 16.7 mm carapace length (CL), respectively. In females, the size at morphological maturity was 18.5 mm CL, whereas size at physiological maturity was 18.25 CL. Ovigerous females were found between June and February in both years. Ovigerous females were found to have oocytes with advanced vitellogenesis. Fecundity was similar in both years and varied between 645 and 7114 eggs. The extended breeding period and the presence of vitellogenic oocytes in ovigerous females suggest the occurrence of two or more spawnings per reproductive season. Finally, the distribution range of this species in the Atlantic Ocean was extended from 43.3° to 45.11°S.

Reproductive anatomy and fecundity estimation of the haematophagous ectoparasite Carnus hemapterus

The dynamics of host-parasite interactions depends to a large extent on the effect of host responses on parasite fitness. An increased research effort is currently being invested in the study of host influence on parasite fitness both at a population and at an individual level even though basic information (e.g. the reproductive anatomy of parasites) is frequently missing. Here, we study for the first time the reproductive system of the diptera Carnus hemapterus, a 2-mm long, highly mobile haematophagous fly parasitizing nestlings of a broad variety of bird species. Although this species is poorly known, it is being increasingly used for the study of host-parasite interactions. We also assess the reliability of a method to estimate fecundity based on the number of laid eggs per gravid female and analyse the effect of body size on fecundity estimates. Our results show that carnid flies are synovigenic, so that both the number of laid eggs at a given moment and the egg load represent only a fraction of the true potential fecundity. Moreover, laid eggs are probably a fraction of the number of mature eggs ready to be laid since females withheld seemingly mature eggs at oviposition. A high proportion of pregnant females did not lay eggs, and the number of eggs laid per pregnant female varied remarkably. The latter is explained partly by a positive relationship with body size (thorax length and abdomen width). Caution is needed when using the number of laid eggs as a shortcut estimation of fecundity in C. hemapterus. We propose some improvements to the method for assessing Carnus fertility.

Sexual maturity of the swimming crab Callinectes danae (Crustacea: Portunidae) at the Santa Cruz Channel, a tropical coastal environment

This paper aims to study the morphological and gonadal maturity of the swimming crab Callinectes danae in the Santa Cruz Channel, Brazil. Crabs of both sexes were measured at carapace width (CW), carapace length (CL), abdomen width (AW), length of the right chelipod (LRC), and dissected to visualize the gonads. The gonadal maturity was estimated based on the frequency of mature individuals per class of CW, and the determination of morphological maturity was based on the relationship between the structures LRC versus CW for males and AW versus CW for females. The sizes that 50% of females reached gonadal and morphological maturity were 62.5 and 59.5 mm CW respectively. In turn, the sizes that 50% of males reached gonadal and morphological maturity were 74.5 and 70.5 mm CW respectively. In the analysis of dispersion of points in relation to AW versus CW, it could be observed that juvenile females showed positive allometry and adult females showed negative allometry, indicating a higher growth rate during the juvenile phase, related to the need of expanding the abdomen for egg incubation at the adult phase. In the relation LRC versus CW, it was observed that both juvenile and adult males showed positive allometry, but changes in the degree of allometry were evident between the two phases. The exceeding growth of the chelipod of males may be related to the reproductive process, including courtship and agonistic interactions with other males.

Maturidade sexual morfológica de Aegla platensis (Crustacea, Decapoda, Anomura) no Lajeado Bonito, norte do estado do Rio Grande do Sul, Brasil

O tamanho da primeira maturação sexual (TPM) em Aegla platensis Schmitt, 1942 foi estimado através das mudanças nas proporções de dimensões corporais dos animais. Para isso, foram realizadas coletas mensais, de julho de 2007 a junho de 2008 no Lajeado Bonito (27º25'27''S, 53º24'39''W), um tributário de primeira ordem do Rio da Várzea, município de Frederico Westphalen, Rio Grande do Sul. Foram utilizados 437 machos com comprimento de cefalotórax (CC) variando de 6,00 mm a 31,75 mm e 368 fêmeas, com tamanhos entre 6,08 mm e 27,92 mm de CC. As seguintes dimensões corporais foram mensuradas em todos os indivíduos coletados: comprimento do cefalotórax (CC), largura do abdome (LA), comprimento do própodo do quelípodo direito (CPD) e comprimento do própodo do quelípodo esquerdo (CPE). Após o registro dessas medidas, os animais foram devolvidos ao mesmo local de captura. As análises de maturidade sexual morfológica foram realizadas com auxílio do software Mature 2, nas quais foram utilizadas as medidas de CC, considerada como variável independente e relacionada com as demais dimensões. As relações que melhor se ajustaram para estas análises, em machos, foram CPD x CC (TPM: CC=18,2 mm) e CPE x CC (TPM: CC=20,1 mm) e LA x CC (TPM: CC=16,5 mm) nas fêmeas.

Population dynamics ofSesarma rectum(Crustacea: Brachyura: Grapsidae) in the Ariquindá River mangrove, north-east of Brazil

This study was carried out in order to provide basic information on the population ecology of the crabSesarma rectumin the Ariquindá River mangrove, Tamandaré, State of Pernambuco, Brazil. The population was analysed with regard to the following aspects, in particular: the size-class frequency distribution of carapace width (CW), mean body size (CW) of males and females, morphological sexual maturity, sex-ratio, reproductive period, and recruitment. Samples were collected monthly from April 2008 through to March 2009; the crabs were collected manually, with a capture effort by one person for 30 minutes, during low tide. The specimens obtained were measured for CW, length of the propodus of males, and abdomen width of females; and the sex and ovigerous condition were noted. Altogether, we obtained 511 specimens (132 juvenile and 137 adult males, and 171 juvenile and 71 adult females, of which 32 were ovigerous). The median CW of males (16.15 mm) was significantly larger than that of females (13.82 mm) (P < 0.05). The size at morphological sexual maturity was 15.73 mm in males and 16.71 mm in females. The sex-ratio for the total of specimens analysed was 1.11:1 (male:female) (P > 0.05). The sex-ratio by size-class showed an anomalous pattern, with a greater abundance of males in the larger size-classes. The reproductive period was continuous and the highest frequency of ovigerous females was recorded in the spring and summer. The major pulse of recruitment occurred during autumn and winter, which is related to greater reproductive activity during the warmer months of the year.

Relative Growth and Its Use to Determine the Morphological Sexual Maturity of Ucides Cordatus (Linnaeus, 1763) (Decapoda, Brachyura, Ucididae) from Two Mangrove Areas on the Northeastern Brazilian Coast

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.

The contribution of naturally occurring food items to the diet of Cherax destructor when fed formulated diets of differing protein levels

To improve growth rates of Cherax spp. raised for human consumption, considerable research has been conducted to establish nutritional requirements for the formulation of a food pellet. The problem with much of this research is that feed requirements between laboratory raised animals and those under pond culture conditions often differ. The difference is thought to be due to the consumption of naturally occurring food sources in addition to formulated pellets. Our study utilised stable isotope techniques to investigate the contribution of naturally occurring food items to the growth of Cherax destructor fed formulated diets differing in composition and raised in two different environments created in artificial ponds. Environment 1 contained no natural food items, whilst environment 2 recreated the naturally occurring food items contained within a commercial growout pond. Dietary treatments 1 and 2 were isoenergetic (12.50 MJ/kg) pellets designed specifically for crayfish, differing only in protein level (30% and 19% crude protein (CP) respectively), dietary treatment 3 was a commercially available pellet used to feed silver perch (40.5% CP, 13.5 MJ/kg) and dietary treatment 4 received no formulated pellets and had access only to naturally occurring food items. Despite the differences between diets and environments, there was no significant difference between weight, abdomen length and abdomen width in any of the fed treatments in either of the environments. Although unfed treatments were significantly smaller in all growth characteristics than fed treatments, those in the natural environment were larger than those in the clean environment. Orbital carapace length (OCL) did not differ between any of the diets or environments. Survival of animals was significantly higher in environment 1 than in environment 2. The cause for this difference was a result of the death of the majority of animals in a single tub. Analysis of C and N stable isotope signatures revealed that animals in environment 1 consumed naturally occurring food items. Of the natural food items available, zooplankton had the largest contribution to the growth of tissue. Microphytobenthos (MPB) also had a significant contribution to animals fed crayfish diet 1. However, despite the contribution of these items to growth, no growth advantage was conferred when pelleted feed was also provided. These results demonstrate that C. destructor consume naturally occurring food items even when provided with a formulated pellet and that suitable growth can be achieved with diets containing CP levels as low as 19%. We recommend testing of even lower protein levels in formulated diets as these may have no negative impact on growth, whilst further reducing the cost of feeds.

Intra-sex dimorphism in crayfish females

A unique cycle of female form alternation has been revealed in an experimental population of Orconectes limosus during a year-long observation. Significant cyclic changes observed in chelae length, width, and robustness, as well as in abdomen width, demonstrated a form alternation similar to that in conspecific males. Small females alternate between sexually active and sexually inactive forms with a short time interval between successive molts as well as different growth patterns of some body parts. Form alternation efficiently produces larger chelae, abdomen, and body dimensions, especially the molt to form I (sexually active). Larger females that undergo only a single annual molt do not alter between forms and are sexually active. They grow slowly and lose chelae robustness. The cycle of form alternation, consisting of two molts per year, may facilitate the effective utilization of resources to increase the size of body parts important to survival and reproduction.

Post-larval morphology, growth, and development of Uca cumulanta Crane, 1943 (Crustacea, Decapoda, Ocypodidae) under laboratory conditions

Studies on the post-larval morphology and growth of crabs can allow correct identification of their early life stages, supporting studies on phylogenetic relationships and ecological aspects. Nevertheless, little is known about the juvenile morphology of ocypodoid crabs worldwide. Uca cumulanta Crane, 1943 is a fiddler crab commonly found in the intertidal zone of the tropical and subtropical western Atlantic. This study describes the morphology of the first juvenile stage of U. cumulanta, its absolute and relative growth, and the appearance and development of its secondary sexual characters. The antennules of U. cumulanta show morphological peculiarities and could probably be used as a distinguishing feature for crabs of this genus. The maxillule and the maxilla have sets of setae forming specialised structures for sorting particles from the sediment. The absolute growth pattern differed statistically between sexes. The study of relative growth revealed differences in the relationships cheliped propodus length (CPL), cheliped propodus height (CPH), and abdomen width (AW) vs. carapace length (CL). These differences between sexes showed that males diverge from females (in the chelipeds) from 3.04±0.11 mm (VI juvenile stage), and females diverge from males (in the abdomen) from 3.84±0.13 mm (VII juvenile stage). The pleopods, rudimentary in the first stage, disappear in the second stage, and then arise in different numbers for each sex from the third juvenile stage on. The spoon-tipped setae found on the second maxilliped, which are used to sort food particles, are evident only from the fourth juvenile stage and increase linearly with carapace growth. The absence of these setae may be the reason why juveniles settle on organic-rich substrates where they can obtain food.

MORPHOLOGICAL STUDY ON CAMPYLOMMA VERBASCI MEYER-DURE (HEMIPTERA: MIRIDAE) AND INSURANCE IT'S CLASSIFICATION AS GENERA AND SPECIES

A new specious Campylomma verbasci was recorded in Syria that causes damage to apple fruits. A newly hatched nymph of C. verbasci collected from infested apple orchards has been reared on Turtica which placed on apple leaf under laboratory conditions during the year 2008 to study of it's morphology. Results showed that its development passes in five nymphal instars to reach adult stage, and we can distinguish between nymphal instsrs by wings pads which appeared in rd nymphal instal- and covered a certain abdomen segment in the next nymphal instars, results showed also there was a significant differences pa0.05 in the following characters body's length, abdomen's width, antenna's length, rostrum's length for nymphal and adult stages

Notes on the biology of the Oriental amblyoponine ant Myopopone castanea: Queen‐worker dimorphism, worker polymorphism and larval hemolymph feeding by workers (Hymenoptera: Formicidae)

AbstractQueen‐worker dimorphism, worker polymorphism and worker behavior in the Oriental amblyoponine ant Myopopone castanea were studied. Queen body size was large (head width, 3.0 mm) with 24 to 32 ovarioles while workers showed a remarkable size variation in both body size (head width 1.48 to 2.18 mm) and ovariole number (6 to 22). Both head width and abdomen width showed allometric growth against thorax width. Workers performed larval hemolymph feeding as was described for Amblyopone silvestrii queens.

Determination of carcass and body fat compositions of grazing crossbred bulls using body measurements1

The objectives of this study were to analyze body measurements of 40 crossbred bulls grazing low quality forage with different supplementation strategies, to estimate interrelationships among those measurements and carcass and body compositions, and to develop systems of equations to predict body fat using body and carcass measurements. Eight animals were slaughtered at the beginning of the experiment, and the remaining animals were slaughtered at 90 or 220 d. The biometric measures (BM) were obtained the day before the slaughter and included hook width, pin width, pelvic girdle length, rump depth, rump height, abdomen width, body length, height at withers, rib depth, girth, and body diagonal length. Other measurements included full, shrunk, and empty BW; internal physical and chemical fats; body volume; body area; carcass weight; 9th- to 11th-rib section weight and composition; fat thickness; subcutaneous fat; intermuscular fat; carcass chemical fat; and empty body physical and chemical fats. The relationships between BM and body components were evaluated, and equations to predict body area, body volume, subcutaneous fat, and carcass and body physical and chemical fat were developed. Biological interpretations of the parameter estimates of equations were similar to those found in the literature such as a ratio of 1 kg of subcutaneous fat to 1.6 kg of intermuscular fat and a deposit of 72 to 76% of body fat in the carcass. The first system used to predict carcass and empty body physical and chemical fat was devised using in vivo information, whereas the second system used BW and the 9th- to 11th-rib fat weight. Our results indicated the combination of BW, carcass traits, and BM was precise and accurate in estimating carcass and body fat composition of backgrounding bulls. The second system had better adequacy statistics [r(2) > 0.92, concordance correlation coefficient (CCC) > 0.957, and root mean square error (RMSE) < 14.4% of the average observed value] compared with the first system. The first system had acceptable adequacy statistics (r(2) > 0.767, CCC > 0.866, and RMSE varying from 15.8 to 22.3% of the average observed value). For both systems, the simultaneous F-test of the linear regression of observed on model-predicted values indicated intercepts were equal to zero, and slopes were equal to 1 (P > 0.246). We concluded that BM can improve the accuracy and precision of the predictions of body composition of grazing animals.

Effects of juvenile non-indigenous Carcinus maenas on the growth and condition of juvenile Cancer irroratus

The Atlantic rock crab, Cancer irroratus, is a commercially fished species and a critical prey item for the American lobster, Homarus americanus, in Atlantic Canada. The recent invasion of European green crab, Carcinus maenas, may have significant effects on the growth and condition of native C. irroratus, because both species overlap spatially and temporally and have similar habitat and dietary requirements. To examine such potential effects, we measured the growth of juvenile C. irroratus in the presence of juvenile C. maenas over a period of 4 months (growing season), under the following species combinations: (1) one C. irroratus (10–25 mm CW); (2) two C. irroratus (10–25 mm CW); (3) one C. irroratus (10–25 mm CW) and one C. maenas (10–15 mm CW). Morphological measurements included pre- and post-molt carapace width, chela height, abdomen width (mm), weight (g), and estimates of molt increment (%) and intermolt duration (days). Analysis of the hepatopancreas for % lipid content at the end of the experiment provided an estimate of physiological condition. The effect of the presence of C. maenas on the growth of C. irroratus shifted from negative to positive, when C. irroratus reached CW of 19–22 mm and gained a presumably significant size advantage over C. maenas. The positive effect resulted from increased energy intake through crab consumption. In the absence of crab consumption, the presence of a second crab (conspecific or C. maenas) had no effect on growth. C. irroratus consumed crabs more frequently when the second individual was a green crab than a conspecific. Consumption of C. maenas had a pronounced effect on the growth rate of C. irroratus, resulting in shorter intermolt periods and larger percent molt increments than in the presence of a conspecific. Therefore, the presence of juvenile C. maenas does not appear to have a prolonged negative effect on the growth of C. irroratus; rather, it may provide an additional food item as rock crabs grow, as long as encounters between the two species occur at high enough rates.

Biometric relationships of the spotted lobster,Panulirus echinatus, from Tamandaré coastal reefs, Pernambuco State, Brazil

Biometric relationships were recorded for 2431 male and femalePanulirus echinatussampled at Tamandaré coastal reefs, Pernambuco, Brazil. The following body measurements were taken: carapace length and width, abdomen length and width, total length, third and fifth pereiopod length, cephalothorax–abdomen and total weight. Twelve relationships were studied to compare the biometric characteristics of males and females. Eleven of them showed difference between the sexes. Comparing sexes with the same carapace length, males have a heavier cephalothorax and longer third and fifth pereiopods than females, whereas females are longer, wider, and have a heavier abdomen than males. For genders with the same total length, males are heavier and have a longer carapace than females, while females have a larger abdomen. For genders with the same abdomen length, males have a heavier abdomen than females. The relationships TWg/TL and AWg/AL showed positive allometric growth for the males. All other relationships involving weight, presented negative allometric growth for both sexes.