Cardisoma Guanhumi Latreille Research Articles

Crustaceans from Tabatinga, coqueirinho and Tambaba beaches, belonging to the environmental protection area Tambaba, Paraíba, Brazil

Most species of crustaceans are part of the most basal levels of the marine trophic web. Their study in Brazil has increased in recent years, but many aspects of crustaceans remain unknown and non-sampled. The littoral of the State of Paraíba, located in northeastern Brazil, remains one of these insufficiently explored areas, despite the increasing environmental impacts due mainly to tourism. This study represents the first inventory of the crustacean fauna of beaches located within the Environmental Protection Area of Tambaba (beaches of Coqueirinho, Tabatinga and Tambaba, located in the municipalities of Conde, Alhandra and Pitimbu, respectively). Sampling was performed as part of the Project Biota - Paraíba (January, 2007 to April, 2009), consisting in manual collecting and shallow snorkeling (down to 0.1 to 0.3 m) during periods of the lowest tides by the research group of the Invertebrate Lab Paulo Young (LIPY), Federal University of Paraiba. More than 250 specimens of crustaceans, belonging to 45 species, were identified. This corresponds to 37.19% of the total species collected along the State of Paraiba during this project. Prominent among these species was Cardisoma guanhumi Latreille 1828, (Gecarcinidae, Brachyura), an important commercial species listed as being overexploited or in risk of overexploitation.

MORPHOMETRY OF BLUE LAND CRAB (CARDISOMA GUANHUMI) BURROWS: ICHNOLOGICAL CONTEXT AND PALEOENVIRONMENTAL IMPLICATIONS

ABSTRACT A large brachyuran, the blue land crab (Cardisoma guanhumiLatreille, 1825) is a keystone species and a prolific burrower in a variety of low-latitude supratidal habitats; however, few studies have addressed its ichnological aspects. Here we present a detailed morphological assessment of C. guanhumi burrows and make comparisons to Macanopsis plataniformis, a trace fossil thought to be constructed by a similar brachyuran. Using nine burrow casts from a mangrove wetland on San Salvador Island, Bahamas, 29 dimensionless morphometric parameters were compared. Results of Bray-Curtis tests show high overall similarity index (0.85) between casts, with complexity, tortuosity, and opening inclination angle having moderate to high similarity (> 0.8). End chamber angle of the blue land crab has highest similarity both within the modern morphometric parameter dataset (> 0.9) and to that of M. plataniformis (0.88). The large terminal chamber is particularly important because of its high preservation potential, as a repository for organic remains, and as a reliable water table (∼ sea-level) indicator. Cluster analysis suggests size-independent Macanopsis-resembling burrow morphology among different extant taxa can be discriminated via quantitative neoichnological methods. Our findings demonstrate how a quantitative assessment of modern burrows and their likely counterparts from the sedimentary record can help constrain tracemaker identity and aid paleoenvironmental reconstruction of low-energy microtidal settings.

Site fidelity and population structure of blue land crabs (Cardisoma guanhumi Latreille, 1825) in a restricted-access mangrove area, analyzed using PIT tags

Understanding the patterns of displacement and site fidelity in blue land crabs (Cardisoma guanhumi Latreille, 1825) has important implications for their conservation and management. The central objective of this study was to analyze seasonal variations in site fidelity in C. guanhumi, a species that is intensively exploited in Brazil, in spite of being part of the Official National List of Critically Endangered Species. This species currently suffers multiple severe threats, such as overharvesting and habitat destruction. C. guanhumi were sampled monthly at four fixed sectors that were delimited at the upper fringe of a restricted-access mangrove at Itamaracá Island between April 2015 and March 2016. One thousand and seventy-eight individuals were captured, measured, sexed, weighed, and their color patterns registered. Of these, 291 individuals were tagged with PIT (Passive Integrated Transponder) tags. Ninety-seven individuals (size range 27.0–62.6 mm carapace width) were successfully recaptured, totaling 135 recapture events. The largest interval between marking and recapture was 331 days. Through the use of mark-recapture-based models, it was possible to estimate the local population as being 1312 (± 417) individuals (mean density 2.23 ± 0.71 ind. m−2). Considering the mean density of burrow openings and individuals, there were 3.4 burrow openings per individual. C. guanhumi showed a clear philopatric behavior. Seventy-seven percent of recaptured individuals were recaptured in their sector of origin, and the remainder in an adjacent sector. Site fidelity was higher in females. Males showed minimum site fidelity in October, which is most likely related to be the onset of the reproductive season. The present study opens new perspectives for the definition of reproductive seasons, based on seasonal changes in behavior, and thus to improve the conservation of exploited and severely threatened species.

Estimation of density and abundance of the blue land crab, Cardisoma guanhumi Latreille, 1828, in the Imburana peninsula, northern Brazil

The blue land crab (Cardisoma guanhumi Latreille, 1828) supports extensive small-scale artisanal fisheries in the tropical western Atlantic, including Brazil. Land surveys were conducted on a peninsula in a northeastern Brazilian estuary in 2014-2015 in order to evaluate density and abundance. The study area (26 700 m2) was dividied into three subareas with a total of 30 sampling points. In all, 529 burrows were registered of which 71.7% were open (indicating activity), 22.1% were closed (indicating moulting) and 6.2% were empty (fishermen catch). Burrow diameter ranged from 12 to 174 mm (mean: 62.05 ± 3.01 mm; 95% confidence interval). The highly significant correlation between mean burrow diameter and mean carapace length (n = 7; R2 = 0.8968, ) shows that one is a good proxy for the other. The estimated total population size in the study area was 10 362 individuals, with a mean density of 0.39 individuals/m2 (stock of 7347 kg).

Population biology and color patterns of the blue land crab, Cardisoma guanhumi (Latreille 1828) (Crustacea: Gecarcinidae) in the Northeastern Brazil.

The objective of this study was to analyze the population biology and color patterns of Cardisoma guanhumi Latreille, 1828 in a mangrove area in Natal, Rio Grande do Norte, Brazil. Crabs were collected monthly between February 2010 and January 2012 and totaled 1,837 individuals. Sex ratios were similar between males and females in the first year and differed in the second. Sex ratios by size class differed statistically in the extremes of the distribution, with an abundance of males in the large size classes. There was no difference (p > 0.05) in carapace width between males and females in the first year, but in the second year, males were larger than females (p = 0.003), showing the importance of considering interannual variation in such studies. Both sexes presented a unimodal distribution. The size of first maturing of the females was 6.00 cm. Asymptotic carapace width for males was 9.4 cm and females for 9.2 cm, using the Wetherall method. There was no defined modal progression, which made the determination of the Von Bertalanffy growth parameter K impossible. Juveniles were found throughout all months of the year, demonstrating that there was no defined period of recruiting, although slightly fewer juveniles were found in the dry season. Four color patterns were observed, the three first patterns were the same for both sexes, while the fourth pattern was observed in females only. The four color patterns identified could be clearly related to the stage of development (size) and sexual maturity of the animal.

Local distribution and abundance of Cardisoma guanhumi Latreille, 1928 (Brachyura: Gecarcinidae) in southern Brazil.

The blue land crab, Cardisoma guanhumi Latreille, 1828 (Brachyura: Gecarcinidae) is officially included in the list of over-exploited species in Brazil, although still abundantly found in the state of Santa Catarina, the southern limit of its distribution. This species was found in forested areas, gardens, and grassy areas, including crabs with carapace width larger than 80mm. The existence of this population with these characteristics is surprising, since there is only one official record of the species in the southern region. The objectives of this study are to estimate the abundance and occupation patterns of C. guanhumi in this region. Correlations with conservation were discussed. The absolute abundance of crabs in the middle of summer activity was established for an area of 100,000 m2. A smaller area was mapped and divided into sampling units for statistical analyses. We distributed approximately 240 crabs in a forested area of about 3,000 m2 and 150 crabs in grassy areas (90,000 m2). The statistical test of Kruskal-Wallis test showed that there are significant differences between the sizes of the openings of the galleries inside the forest and that located in grassy areas. In the forest, the openings tend to be much larger. Burrows were found at a distance of 150 metres from the channel. The number of galleries was higher in the forested area, although the burrows were more densely grouped in grassy areas. Although C. guanhumi seems to be adjusting well to changes caused by human occupation, small forested areas are more conducive to growth and conservation of this species.

Characterization of microsatellite markers from the commodity species Cardisoma guanhumi Latreille and the Christmas Island blue crab (Discoplax celeste)

Cardisoma guanhumi Latreille, the blue land crab, is overharvested throughout its range, resulting in harvesting regulations in multiple countries/protectorates. A lack of polymorphic markers hampers genetic-based conservation for the species. Here, we present 13 loci, eight of which are polymorphic in the heavily collected popu- lations of C. guanhumi on Andros Island, The Bahamas. Overharvesting of Androsian crabs may have reduced diversity, so both monomorphic and polymorphic loci are presented. Five of the loci were found to be polymorphic in Discoplax celeste, the Christmas Island blue crab.

Development of male reproductive system of the blue land crab Cardisoma guanhumi Latreille, 1828 (Decapoda: Gecarcinidae)

AbstractShinozaki‐Mendes, R.A., Silva, J.R.F. and Hazin, F.H.V. 2011. Development of male reproductive system of the blue land crab Cardisoma guanhumi Latreille, 1828 (Decapoda: Gecarcinidae). —Acta Zoologica (Stockholm) 93: 390–399.In this study, the reproductive tract of the Cardisoma guanhumi was described both macroscopically and microscopically. The maturation stages of the reproductive system were defined, and the development of germ cells was described. The reproductive tract is made up of a pair of testis, a pair of vas deferentia, and a pair of ejaculatory ducts. The germ cells were classified in the order of development as spermatogonia (diameter: 10.5 ± 0.11 μm), spermatocytes (9.7 ± 0.07 μm), spermatids (initial phase: 5.5 ± 0.06 μm; final phase: 4.3 ± 0.05), and spermatozoa (SPZ) (4.0 ± 0.03 μm). The testis is made up of a germ zone, a maturation zone and collector ducts, which lead to the anterior vas deferens (AVD), containing solely SPZ. The spermatophores (SPH) start to be formed in the AVD, through the secretion of spermatophoric and protein matrices. In the median vas deferens, the SPH, already fully formed, are stored, while in the posterior vas deferens, a large production of a glycoprotein matrix is observed. Based on macroscopic and microscopic description of the male reproductive tract, three maturation stages are proposed: immature, maturing, and mature.

Further observations on zooplankton of the Potengi Estuary (Natal, Rio Grande do Norte, Brazil) with special reference to the larvae of Brachyura (Crustacea, Decapoda)

The present paper deals with data on zooplankton collected from the estuary of Potengi, Natal, Rio Grande do Norte, Brazil covering a period of one year from October 1992 to October 1993. Three fixed stations within the estuary located at varying distances from the mouth of the river were sampled. Sampling was done monthly when the tide was lowest. Analysis of the samples has shown clear pattern of seasonal variations in abundance of the dominant zooplankton components which are composed of Copepoda, Appendicularia, larvae of Brachyura, larvae of Cirripedia and Chaetognalha. A detailed study of the larvae of Brachyura was also attempted which showed that seven species can be identified in the samples, of which those of Aratus pisonii (H. Milne Edwards) and Cardisoma guanhumi Latreille have already been described. Other five species are designated here numerically and description of various stages present in the samples are given.

Specific dynamic action and the metabolism of the brachyuran land crabs Ocypode quadrata (Fabricius, 1787), Goniopsis cruentata (Latreille, 1803) and Cardisoma guanhumi Latreille, 1825

Oxygen uptake (MO 2) was measured in the terrestrial crabs Ocypode quadrata (Fabricius, 1787), Goniopsis cruentata (Latreille, 1803) and Cardisoma guanhumi Latreille, 1825 as a function of digestive state to determine the magnitude and time course of specific dynamic action (SDA). Following 5 days of feeding ad libitum on fish flesh, “steady-state” MO 2 was about 2.8, 1.0 and 1.6 μm·g −1·h −1 in Ocypode(29–31 °C), Goniopsis (23–25°C) and Cardisoma (29–31 °C), respectively. After 5 days of fasting, “steady-state” MO 2 was decreased greatly to 1.0 and 0.5 μm·g −1·h −1 in Ocypode and Cardisoma, respectively, but was not significantly changed from feeding values in Goniopsis. Time-course experiments indicated that the peak in MO 2 following a single large meal occurred within 8 h in both Ocypode and Cardisoma. The apparent SDA persisted for longer than 50 h in Cardisoma, but less than 42 h in Ocypode. These data show that an apparent SDA of large magnitude and variable time course can occur in land crabs. However, the absence of any apparent SDA effect in Goniopsis indicates that it is not a necessary accompaniment to feeding in all terrestrial brachyurans, and must be verified on a species-by-species basis.

Sensory Basis and Functional Role of Eye Movements Elicited During Locomotion in the Land Crab Cardisoma Guanhumi

ABSTRACT Eye movements in the horizontal plane and the rotatory component of body movement have been continuously recorded in land crabs, Cardisoma guanhumi Latreille, walking freely in an arena. The results show that the eyes compensate for locomotor turns by moving in the opposite direction to the body, thus reducing the image motion of surrounding objects on the retina. Gains often approach unity, so that stabilization of the rotatory component of self-generated image motion is good. Of the three compensatory eye reflexes that could contribute to these responses, optokinetic responses play a major role, since the gain of the responses of freely walking blinded crabs was about half that of crabs that could see. Since blinded crabs held above a ball moved their eyes whenever they rotated the ball about a vertical axis (i.e. turned), a significant role for leg proprioceptor-driven eye movements is also presumed. It is unclear whether vestibular nystagmus, driven by the statocysts, also has a role to play. In contrast to the high-gain compensatory responses that accompany turns, the translatory component of locomotion elicits compensatory eye movements only under the most favourable circumstances, when the crab walks along a runway facing a set of stripes. Even then, the responses are of very low gain (0.02-0.09). Amongst several possible factors, this is partly because lateral ommatidia, which drive the optokinetic responses, will face the poles of the flow field during sideways walking, and partly because stationary contrasts (as occur at the poles of the flow field) reduce the gain of optokinetic responses. It is argued that, by compensating for turns but not translatory locomotor movements, crabs effectively separate the rotatory from the translatory components of the visual flow field around them. Since only the former can be used in course control, while only the latter provides information on ground speed and the three-dimensional layout of the environment, such a separation makes good functional sense.

Urine production rate and water balance in the terrestrial crabs Gecarcinus lateralis and Cardisoma guanhumi.

1. The rate of urine production in the terrestrial crabs Gecarcinus lateralis (Freminville) and Cardisoma guanhumi Latreille maintained on s.w.-moist sand was measured by inulin clearance. 2. The inulin U/B ratios in both species rose to about unity after 48 h, and remained at this level. It was concluded that neither species withdrew water from the primary urine. 3. The relatively high rate of inulin clearance in G. lateralis (10-69% body wt day-1) was considerably reduced when animals were transferred to dry sand (2-15% body wt day-1). 4. The rate of water loss on dry sand was measured in G. lateralis and changes in the haemolymph and urine osmolality recorded. 5. The prevention of possible reabsorption of water from voided urine did not appear to affect significantly the rate of water loss in conditions of water deprivation. 6. The maintenance of urine production rates measured on s.w.-moist sand would double the water loss of G. lateralis in dry conditions.

Responses to respiratory stress in relation to blood pigment affinity in Goniopsis cruentata (Latreille) and (to a lesser extent) in Cardisoma guanhumi Latreille

The crabs Goniopsis cruentata (Latreille) and Cardisoma guanhumi Latreille are shown to be metabolic regulators at environmental temperatures. Haemocyanin P 50 in Goniopsis shows strong correlation with maximum standard respiratory rates ( R max ) and critical oxygen tension ( P c ) and also with lethal oxygen tensions ( P L ), at different temperatures. The hypothesis that the P c represents that P o 2 at which the blood pigment fails to become saturated in the gills, though qualitatively in accord with these correlations, is irreconcilable with metabolic regulation in these animals. An alternative hypothesis is tentatively suggested from which, like the previous hypothesis, the experimental relationship P c ∝ ( R max ) ( P 50) can be derived. The new hypothesis leads to the conclusion that the P c reflects the initiation of anaerobiosis. Altogether, the evidence is thought to suggest that the graphical correlations are causal and that pigment affinity plays a determining role in the responses to respiratory stresses, both thermal and anoxic.

The physiological ecology of haemocyanin in some selected crabs. II. The characteristics of haemocyanin in relation to terrestrialness

The haemocyanins of five crabs ranging in habit from aquatic to terrestrial have been investigated. The mean P 50 values of the respiratory pigments were determined at 0 mm Hg CO 2 and 28 °C (the average environmental temperature of all the species). Comparison of these data adjusted to the individual mean physiological pH indicate an increase in P 50 with terrestrialization, perhaps related to the greater abundance of oxygen in the aerial than in some the aquatic habits, and the progressive elaboration of lung breathing with terrestrialization. The Bohr shifts ( Δ log P 50 ΔpH ) were determined (using different P CO 2 values to vary pH) and were found to decrease with terrestrialization, perhaps in adaptation to an associated rise in internal P CO 2 (6–8-fold between the aquatic Callinectes sapidus Rathbun and the terrestrial Cardisoma guanhumi Latreille and probably resulting from progressive gill reduction. The temperature shifts (ΔH cal/mol) of the haemoeyanins were found and it is suggested that they diminish with increasing evironmental temperature and temperature fluctuation accompanying terrestrialization.