ABSTRACT The southern banded guitarfish, Zapteryx xyster, and the Velez ray, Raja velezi, are two endemic elasmobranchs in the eastern Tropical Pacific that are commonly caught by the bottom-trawl fishery. Reproductive cycles of these batoids were inferred from the hepatosomatic and gonadosomatic indexes (males and females) and the oviductal gland width and the yolk follicle diameter (females) of mature specimens collected along the Pacific of Costa Rica between 2010 and 2011. Z. xyster females have a partially defined annual cycle with one reproductive peak in June and July, with most neonates and gravid females occurring during December and January (beginning of the dry season). The gestation period of Z. xyster can range between four and six months; males are probably capable of mating continuously throughout the year. Females and males of R. velezi have a continuous reproductive cycle with no clear peaks. Management and conservation measures of these batoids should consider their reproductive ecology, which may be linked to the degree of vulnerability to fishing. Based on our findings, we recommend reducing fishing pressure when mating (June-July) and pupping (December-January) of Z. xyster occur. In contrast, a reduction of fishing pressure on previously identified nursery grounds of R. velezi in the southern Pacific of Costa Rica may benefit their population.

Abstract Freshwater crabs are macroconsumers that are commonly found in Neotropical headwater streams that may play a key role in energy flow and nutrient cycling in detrital food webs. Although studies have examined the feeding habits of trichodactylid crabs, little is known of this behavior in pseudothelphusid species, and specifically whether they actually consume leaf material. We conducted three nine-day laboratory trials with pseudothelphusid crabs (Ptychophallus tumimanus (Rathbun, 1898)) and leaves (Koanophyllon pittieri) to investigate whether crabs shred leaves. We hypothesized that leaf mass loss would be faster with crabs present relative to control tanks with only leaves. Leaf mass loss was significantly higher (p < 0.001) in tanks with crabs (0.49 ± 0.07 g, mean ± 1 SD) compared to control tanks (0.31 ± 0.05 g). We observed crabs manipulating, shredding, and consuming leaves, with leaf fragments and egesta present in tanks with crabs but not in control tanks. Their consumption and egestion activity may affect nutrient availability and transformation by stimulating microbial activity during leaf breakdown and converting coarse particulate organic matter (CPOM) to fine particulate organic matter (FPOM). Therefore, freshwater crabs need to be considered when studying energy flow and nutrient cycling in detrital food webs of Neotropical headwater streams.

Abstract A new behavior related to shell care was recently reported for the intertidal hermit crab Clibanarius erythropus (Latreille, 1818) in the Gulf of Cádiz (southwestern Europe). It also has been observed in other species of the diogenid genera Clibanarius Dana, 1952, and Calcinus Dana, 1951, however, it has not been described as an active behavior. In the present study, intertidal hermit crabs from different species and localities were sampled to assess if air-exposure is a shell cleaning behavior restricted to some species of intertidal hermit crabs or if it is a more generalized behavior among species inhabiting intertidal habitats. The results revealed that air-exposure is an active behavior in species of Clibanarius and Calcinus, since we observed it also in Clibanarius albidigitus Nobili, 1901, and Calcinus obscurus Stimpson, 1859, from the Pacific coast of Costa Rica, although not in other intertidal species studied by us. We found interspecific differences in tolerance to physical stress of emerged hermit crabs. This air-exposure tolerance can be interpreted as a physiological adaptation to desiccation stress and is also related to the shell type they inhabit. Also, we provide additional features and details of the air-exposure behavior, combining observations of the first description in 2015 with our new field observations.

ABSTRACT Primary freshwater crabs are an important component of the food web in aquatic ecosystems, but our knowledge about the role of these decapods as predators and as prey is far from complete. Here we report observations of the feeding habits of the pseudothelphusid crab Ptychophallus uncinatusCampos & Lemaitre, 1999, made in 2013 during exploratory observations after sunset in the dusk and darkness of the early evening within the Veragua Rainforest Research & Adventure Park, Limón Province, in the Atlantic drainage of Costa Rica. We observed a case of cannibalism where an adult P. uncinatus was feeding on a smaller crab. Furthermore, P. uncinatus was observed to prey on an insect larva, a frog, and a lizard on three separate occasions. Additionally, a spider of the family Ctenidae was discovered feeding on a specimen of P. uncinatus. These observations revealed novel information about the role of P. uncinatus as both a predator and as an item of prey in a Neotropical freshwater ecosystem.

ABSTRACT Our knowledge of the reproductive biology of palaemonid shrimps is an important tool to assess potential candidates for aquaculture as well as being useful to develop adequate strategies for the conservation of the biodiversity. Here we analyzed the fecundity, volume and water content of the eggs, and the reproductive output (RO) of Macrobrachium tenellum in the Ameca River, Jalisco-Nayarit, Mexico. The total length of the females ranged from 26.6 to 67.0 mm (average 44.2 ± 8.8 mm) and fecundity (considering all stages) fluctuated between 253 and 10,384 eggs (average 2,418 ± 2,089 eggs). Females lost on average 26% of the initially produced eggs. The average egg length increased from 0.55 (recently produced eggs) to 0.66 mm (eggs close to hatching). The water content of eggs increased significantly during embryogenesis by 11.4%. The RO was not related to female length and fluctuated between 4.1 and 16.0%, which are values within the range reported for other decapods. The results of the current research contribute to laying the foundations for future studies that help to define strategies for the conservation and sustainable use of this crustacean.

ABSTRACT The freshwater shrimp genus Macrobrachium is highly diverse, distributed in tropical and subtropical regions around the world, and of considerable commercial importance in many countries. Here we present the results of an analysis of the scientific production regarding Macrobrachium published between 1980 and 2016 in the database Web of Science. The evaluated indicators were key words and authors producing the scientific literature about this genus. Concept maps and cluster analysis techniques were used to display the relationships between them. The results of the study visualize the temporal development of scientific knowledge of the genus Macrobrachium and describe the development of authorship networks during 36 years study period. Moreover, the results of the analysis show emerging research trends in the field of Macrobrachium studies.

ResumenExiste una creciente necesidad de fortalecer el sector de la pesca de pequeña escala con métodos de gobernanza emergentes que mejoren las estrategias de subsistencia de los pescadores. Por lo tanto, el presente estudio se centró en el desarrollo de recomendaciones de manejo, basadas en conclusiones fácilmente interpretables, que ayuden a atender las dificultades socio-ecológicas que enfrentan los pescadores artesanales que utilizan líneas de fondo en Bejuco, Pacífico de Costa Rica. Se asignó un conjunto medible de indicadores para cada sub-sistema (natural, humano y manejo) de la pesquería a partir de los resultados de un análisis previo de las percepciones socioecológicas de los pescadores y una evaluación de aspectos biológico-pesqueros para el pargo manchado Lutjanus guttatus. Se usó la técnica de semáforo con la cual se asignaron colores para la evaluación de indicadores construidos con base en la revisión de literatura publicada. Se propusieron recomendaciones de manejo basadas en los resultados. Se sugiere un análisis del estado del stock de la principal especie objetivo de pesca y un estudio que determine la magnitud y composición de las especies descartadas. Debido a la alta dependencia económica de los pescadores, se recomienda la implementación de programas que permitan el desarrollo de opciones alternativas del empleo. Además, se recomienda promover mercados alternativos y sistemas de certificación sostenible para la captura de pargo manchado. También se recomienda la ampliación de las áreas marinas protegidas de uso múltiple de la zona. Para esto es necesario mejorar la coordinación y participación de los usuarios mediante la formación de una asociación que tenga la capacidad de vincular a la contraparte gubernamental en la solución de múltiples limitaciones y problemas (p. ej pesca ilegal) en la actividad pesquera de Bejuco.Esto facilitaría la construcción de un plan de manejo local bajo un sistema de gobernanza participativa.

AbstractThere is a growing need to strengthen the small-scale fishing sector with emerging governance methods that improve fishers’ threatened livelihoods. Therefore, this study’s aim was to develop management recommendations, based on easily interpreted conclusions that can be used to address the socio-ecological difficulties that the artisanal, bottom-longline fishery in Bejuco, Pacific coast of Costa Rica faces. The results of previously recorded fisher socio-ecological perceptions and an evaluation of the spotted rose snapper’s, Lutjanus guttatus, population dynamics were assigned a measurable set of indicators in reference to the fishery’s natural, human and management sub-systems. This was done via the traffic light method with easily interpreted colors based on a review of similar published fisheries studies. According to these results, a stock assessment for the fishery’s target species and research to determine the composition and magnitude of the fishery’s discarded species were recommended. Fisher economic dependence on bottom-longline activities led to the recommendation to develop alternative livelihood strategies. Also, the promotion of alternative markets and sustainability certification strategies for the snapper fishery are advised. Enlargement of the multi-use marine protected areas within the fishery’s grounds and improvement of their management strategies is also recommended. In order for this to occur, improved resource user coordination in the form of a fisher association that has the capability to lobby for increased enforcement of the protected areas from destructive fisheries must be realized. Doing so would aid the development of a local management plan and participatory governance system. Such an initiative would justify the development of community lead marine protected area management regimes.

The deep-water shrimp fishery is of great commercial importance along the Pacific coast of Latin America. In Costa Rica, shrimp resources have declined considerably over the last decade. Therefore, fisheries have shifted towards teleost species such as the Pacific bearded brotula Brotula clarkae. Little is known about the biology and life history of this species, which is becoming increasingly valuable to artisanal and semi-industrial fishers in Costa Rica. A sample of 348 B. clarkae was obtained along the Pacific coast of Costa Rica between March 2011 and July 2012 to obtain baseline information of this species. The results revealed that the size at sexual maturity of B. clarkae was 71.9 cm T L, considerably higher than previously reported for South American populations. Since the size at maturity may vary between populations in different geographic locations, detailed information of the reproductive biology of widely distributed species such as B. clarkae is critical for developing effective management approaches.

La pesca de camarón de aguas profundas es de gran importancia comercial en la costa Pacífica de Latinoamérica. En Costa Rica, el recurso camarón ha disminuido considerablemente durante la última década. Como consecuencia, la pesquería ha comenzado a explotar otras especies como, el congrio rosado Brotula clarkae. Poco se sabe de la biología de esta especie con valor comercial en las pesquerías artesanales e industriales de Costa Rica. Una muestra de 348 B. clarkae fue obtenida a lo largo de la costa Pacífica de Costa Rica entre marzo 2011 y julio 2012 para obtener información base de esta especie. La talla de madurez sexual fue 71.9 cm T L, siendo considerablemente mayor que la reportada previamente para poblaciones de Sudamérica. Dado que la talla de madurez sexual puede variar entre poblaciones de diferentes áreas geográficas, información acerca de la biología reproductiva de una especie tan ampliamente distribuida es crucial para diseñar estrategias adecuadas de manejo.

La selección de sitio de anidación por parte de individuos de la tortuga baula, Dermochelys coriacea, es tema de discusión. Algunos autores sugieren que una hembra dispersa sus nidos al azar para maximizar su éxito en las inestables playas que elige para anidar, mientras que otros sugieren que existe cierta fidelidad al sitio de anidación. También es posible que ambas estrategias existan, dependiendo de las características de la playa donde anidan, así playas estables llevarían a las hembras a repetir la selección de sitio mientras que las playas inestables las llevarían a dispersar sus nidos. Para determinar la estrategia que usan las hembras de D. coriacea de Tortuguero, se estudió la preferencia de sitio de las hembras así como su repetición en este sitio, desde 1997 hasta 2008. Para la selección de sitio vertical (perpendicular a la costa), las hembras en general prefirieron anidar en arena abierta, independientemente de su escogencia inicial. Esto muestra una tendencia a dispersar los nidos y es consistente con la alta variación en los éxitos de eclosión en todas las zonas, así como la falta de relación entre los éxitos de eclosión de nidos subsecuentes, lo cual muestra que el éxito de los nidos no es predecible. Para la selección horizontal (a lo largo de la costa) se prefirió la parte media de la sección estudiada de la playa, tanto a nivel poblacional como individual (repetición de selección de sitio). Interesantemente, esta zona tiene la mayor cantidad de luces artificiales lo cual lleva a éxitos de eclosión ligeramente más bajos (aunque no significativamente) y a la desorientación de neonatos. Este resultado amerita estudios futuros para determinar si se trata de una tendencia maladaptativa en la población y muestra la importancia de controlar la cantidad de luz artificial en esta playa como medida de conservación.

Nest site selection for individual leatherback sea turtles, Dermochelys coriacea, is a matter of dispute. Some authors suggest that a female will tend to randomly scatter her nests to optimize clutch survival at a highly dynamic beach, while others suggest that some site fidelity exists. It is also possible that both strategies exist, depending on the characteristics of each nesting beach, with stable beaches leading to repeating nest site selections and unstable beaches leading to nest scattering. To determine the strategy of the Tortuguero population of D. coriacea, female site preference and repetition were determined by studying whether females repeat their nest zone choices between successive attempts and whether this leads to a correlation in hatching and emergence success of subsequent nests. Nesting data from 1997 to 2008 were used. Perpendicular to the coastline, open sand was preferred in general, regardless of initial choice. This shows a tendency to scatter nests and is consistent with the fact that all vertical zones had a high variability in hatching and emergence success. It is also consistent with nest success not being easily predictable, as shown by the lack of correlation in success of subsequent nesting attempts. Along the coastline, turtles showed a preference for the middle part of the studied section of beach, both at a population level and as a tendency to repeat their initial choice. Interestingly, this zone has the most artificial lights, which leads to slightly lower nest success (though not significantly so) and hatchling disorientation. This finding merits further study for a possibly maladaptive trait and shows the need for increased control of artificial nesting on this beach.

Some members of the Pinnotheridae family exhibit close symbiotic relationships with bivalves, which may cause severe damage to the mollusk. The condition index (CI) is a tool that serves to evaluate the effect of biotic and abiotic factors on the morphology and physiology of mollusks, including those caused by symbiotic organisms. In the present study, we evaluated the effects of the infestation of the pinnotherid crab Austinotheres angelicus on the oyster Saccostrea palmula through monthly sampling (April to November 2012) in Punta Morales, Pacific coast of Costa Rica. A total of 245 oysters were analyzed, of which 38% were infested by the pinnotherid crab. Most of the oysters analyzed (92%) varied in depth between 1.5 and 15.0 mm; 89% of the infested oysters were in this depth range. The prevalence was positively correlated with the depth of the oyster. Our results revealed that crab infestation could reduce the CI by 11 to 33%. The obtained findings suggest that the infestation by A. angelicus provokes alterations of the flesh production of the oyster, especially when the association is with a pair of crabs including an ovigerous female. The association of A. angelicus with S. palmula is best described as facultative parasitism for male crabs and obligatory parasitism for females.

The caridean freshwater shrimp Atya scabra is a common resident of stream systems of tropical rainforests in America, including Brazilian drainages. This shrimp has an amphidromous life cycle, which increases its vulnerability when facing habitat fragmentation. Since information on the reproduction of this species is still limited, we present here data on egg production, egg loss, and energy investment, to achieve a better understanding of reproductive features of A. scabra. Specimens were collected between 2006 and 2007 in São Sebastião Island, southeastern Brazil, in 13 locations. The fecundity of 21 ovigerous females analyzed ranged between 414 and 19,250 eggs, which were higher than previously reported. However, the larger size of females analyzed may explain the observed intraspecific difference in egg production. During embryogenesis, egg volume and water content increased by 103 and 22.6%, respectively. The initial egg volume of A. scabra in the present study (0.027 mm³) was slightly lower, but comparable to the values reported previously from the same study area. During incubation, females of A. scabra lost 15% of their initially produced eggs. The reproductive output (average RO of 3.6%) is the first report for any atyid species. Its value is fairly low compared to other freshwater shrimps, and it is hypothesized that this might be related to a high energy investment in morphological adaptations, which allows the shrimp to cling on to the substrate in the fast flowing environment they inhabit. Additionally, the long life span, a well-known phenomenon in atyid shrimp, may allow the species to invest a relatively low amount of energy per brood in egg production, but over a longer time span.

El camarón carídeo de agua dulce, Atya scabra, es un residente común del sistema de arroyos de los bosques tropicales de América, incluyendo drenajes brasileños. Este camarón tiene un ciclo de vida anfídromo, lo que aumenta su vulnerabilidad al enfrentar la fragmentación del hábitat. Dado que la información sobre la reproducción de esta especie es todavía limitada, se presentan datos sobre producción de huevos, pérdida de huevos e inversión energética, para lograr una mejor comprensión de los aspectos reproductivos de A. scabra. Los especímenes fueron recolectados entre 2006 y 2007 en la isla São Sebastião, al sureste de Brasil, en 13 localidades. La fecundidad de las 21 hembras ovígeras analizadas varió entre 414 y 19,250 huevos, valores que son más altos que los reportados previamente, sin embargo, el mayor tamaño de las hembras analizadas podría explicar la diferencia intraespecífica en la producción de huevos. Durante la embriogénesis, el volumen del huevo y el contenido de agua aumentó en 103 y 22,6%, respectivamente. El volumen inicial del huevo de A. scabra en este estudio (0,027 mm³), fue ligeramente inferior, pero comparable con los valores reportados anteriormente para la misma área de estudio. Durante el periodo de incubación, las hembras de A. scabra pierden el 15% de los huevos producidos inicialmente. El rendimiento reproductivo (RO promedio de 3,6%), es el primer valor reportado para cualquiera de las especies de la familia Atyidae. Este valor, es relativamente bajo en comparación con otros camarones de agua dulce, y se plantea la hipótesis de que esto podría estar relacionado con una alta inversión energética en adaptaciones morfológicas, lo que permitiría al camarón aferrarse al sustrato en las fuertes corrientes que habita. Además, la alta expectativa de vida, un fenómeno bien documentado en atyidos, podría permitir a las especies una menor inversión energética por camada de huevos, pero por un periodo de tiempo más prolongado.

During the last decades, knowledge on biodiversity of freshwater decapods has increased considerably; however, information about ecology of these crustaceans is scarce. Currently, the freshwater decapod fauna of Costa Rica is comprised by representatives of three families (Caridea: Palaemonidae and Atyidae; Brachyura: Pseudothelphusidae). The present study aims to describe the species diversity and distribution of freshwater crabs inhabiting the basin of the Rio Grande de Térraba, Pacific slope of Costa Rica, where the Instituto Costarricense de Electricidad (ICE) plans to implement one of the largest damming projects in the region. Samples were collected in 39 locations at an altitude ranging from 20 to 1,225 m. Sampling was carried out during several months in 2007, 2009 and 2010. We collected a total of 661 crabs, comprising eight species of Pseudothelphusidae of three genera, representing 53% of the 15 pseudothelphusid crab species currently recorded from Costa Rica. The most common species was Ptychophallus paraxanthusi followed by P. tristani. Freshwater crabs were more frequently encountered in the middle-low region of the basin (between 311 and 600 m) and less frequently in the medium-high basin (between 601 and 1,225 m). Ptychophallus paraxanthusi showed the widest distribution and was collected in altitudes ranging from 20 to 700 m. The Rio Grande de Térraba region can be considered as a relatively small, but highly diverse system. Therefore, any alteration of the basin of Rio Grande de Térraba, and especially the possible construction of a hydroelectric power plant, needs to be carefully analyzed to mitigate the damaging effects of this project on the freshwater crabs. More ecological information about freshwater crabs from Costa Rica and the Central American region are needed to reach a first reasonable overview on the ecological role of these decapods in freshwater systems.

El conocimiento de la biodiversidad de decápodos de agua dulce ha aumentado considerablemente durante las últimas décadas. Sin embargo, información sobre la ecología de estos crustáceos es limitada. Actualmente, la fauna de los decápodos de agua dulce está compuesta por representantes de tres familias (Caridea: Palaemonidae y Atyidae; Brachyura: Pseudothelphusidae). El presente estudio describe la diversidad de especies y la distribución de cangrejos de agua dulce de la cuenca del Río Grande de Térraba, vertiente Pacífica de Costa Rica, donde el Instituto Costarricense de Electricidad (ICE) está planeando construir una de las plantas hidroeléctricas más grandes de la región. Las muestras fueron recolectadas en 39 localidades a una altitud entre 20 y 1.225 m. El muestreo se efectuó durante varios meses de los años 2007, 2009 y 2010. Se colectó un total de 661 cangrejos de ocho especies de Pseudothelphusidae de tres géneros, lo que representa un 53% de las 15 especies de Pseudothelphusidae actualmente reportado para Costa Rica. La especie más frecuentes fue Ptychophallus paraxanthusi, seguida por P. tristani. Los cangrejos de agua dulce fueron más frecuentes en la región medio-baja de la Cuenca (entre 311 y 600 m) y menos frecuentes en la región medio-alta (entre 601 y 1.225 m). Ptychophallus paraxanthusi demostró la distribución más amplia y fue colectado en altitudes entre 20 y 700 m. Se puede considerar el Río Grande de Térraba un sistema pequeño, pero altamente diverso. Por lo tanto, cualquier alteración de la Cuenca del Rio Grande de Térraba, y especialmente la posible construcción de la planta hidroeléctrica, requiere un análisis cuidadoso para mitigar efectos dañinos de este proyecto sobre los cangrejos de agua dulce. Se requiere más información ecológica sobre los cangrejos de agua dulce de Costa Rica y la región de Centro América para obtener una primera visión razonable del rol ecológico de estos decápodos en los sistemas dulceacuícolas.

Commercial fisheries are expanding their activities into deeper water. The life history features of these deep-water resources make them more vulnerable to exploitation than most shallow-water resources. Moreover, the apparent lack of solid information about the ecology of most deep-water species represents a major limitation for the development and implementation of management strategies. This scenario has caused great concern regarding the sustainability of these resources and the possible environmental impacts on the deep-sea ecosystem. In Latin America, commercial fisheries are going deep as well, and considering the above-mentioned concerns, we felt the need to compile the available information about the deep-water shrimp resources and the current status of their fisheries in Latin America. Focusing on Mexico, Central America, Peru, Chile and Brazil, this review describes the exploited species, and, whenever available, the fishing fleet, fishery statistics, and management strategies. A total of 17 species (10 spp. of Penaeoidea; 7 spp. of Caridea) are of commercial interest in Latin America, but deep-water shrimps are currently fished only in Costa Rica, Colombia and Chile. An implemented management plan exists in Chile and Colombia, while Brazil approved fishery regulations for the aristeid fishery, which were never implemented. Considering the lack of information about the biology of the deep-water shrimps, which hinders the development of adequate management strategies, we see the urgent need to improve the communication and collaboration between the different stakeholders in Latin American. We suggest the establishment of a searchable and constantly updated database, which may serve as a valuable source of information for researcher and decision makers. Finally, we propose the development of regional research plans aimed towards supporting measurements for a sustainable use of deep-water shrimps in Latin America.

La pesca comercial está expandiendo sus actividades hacia aguas profundas. Las características del ciclo de vida de estos recursos de aguas profundas los hacen más vulnerables a la explotación que la mayoría de los recursos de aguas someras. Además, la falta de información sobre la ecología de la mayoría de las especies de aguas profundas constituye una limitación importante para el desarrollo e implementación de estrategias de manejo. Este escenario ha causado preocupación sobre la sustentabilidad de estos recursos y de los posibles impactos ambientales en los ecosistemas de aguas profundas. La pesca comercial en América Latina se extiende también hacia aguas profundas y, considerando las preocupaciones anteriormente mencionadas, se requiere la necesidad de compilar la información disponible sobre los recursos de camarones de aguas profundas y la situación actual de estas pesquerías en América Latina. Esta revisión se enfoca en México, Centro América, Perú, Chile y Brasil y describe las especies explotadas, la flota pesquera (siempre cuando sea disponible), las estadísticas pesqueras y las estrategias de manejo. Un total de 17 especies (10 spp. de Penaeoidea y 7 spp. de Caridea) son de interés comercial en América Latina; sin embargo, camarones de aguas profundas solo se pescan actualmente en Costa Rica, Colombia y Chile. Un plan de manejo implementado existe en Chile y Colombia, mientras que en Brasil se aprobaron regulaciones sobre la pesca de camarones de la familia Aristeidae, pero éstas nunca han sido implementadas. Considerando la falta de información sobre la biología de los camarones de aguas profundas, lo que dificulta el desarrollo de estrategias adecuadas de manejo, se requiere urgentemente mejorar la comunicación y colaboración entre los diferentes actores en Latinoamérica. Se sugiere establecer un banco de datos abierto para búsquedas y actualizarlo constantemente, lo que servirá como fuente valiosa de información para investigadores y quienes deben tomar decisiones. Finalmente, se propone desarrollar un plan de investigación para apoyar medidas hacia el uso sustentable de camarones de aguas profundas en América Latina.

Lobster fishery (Panulirus argus) forms an important part of the fishing activities along the Caribbean coast of Central America. The present study provides information regarding the seasonal abundance and distribution of postlarval P. argus in Parque Nacional Cahuita, Costa Rica. During the study period (March 2004-February 2005), a total of 1907 pueruli were obtained from GuSi collectors. Postlarvae were present during all months, with a pronounced peak in January-February 2005 (CPUE of 21.82 and 22.18, pueruli/collector/month, respectively), and minor peaks in May and October 2004. The abundance of postlarval P. argus in the study area was comparable to locations which support important lobster fisheries, e.g. Mexico. A majority of the postlarvae (1027 ind.) was collected during the first quarter moon, the remaining pueruli (880 ind.) during new moon; these results are in general agreement with similar findings for P. argus in the Caribbean area. Based upon our results, we recommend introducing a local or regional monitoring program, studying spiny lobster migration and distribution patterns, and evaluate the introduction of artificial shelters for P. argus.

Las capturas de langosta (Panulirus argus) son de gran importancia en la actividad pesquera a lo largo de las costas del Caribe de Centroamérica. El presente estudio proporciona información relevante de la abundancia temporal y la distribución de postlarvas de P. argus en el Parque Nacional Cahuita, Costa Rica. Durante el periodo de estudio (Marzo 2004-Febrero 2005), un total de 1907 puérulos fueron obtenidos del colector GuSi. Las postlarvas fueron colectadas durante todos los meses, con máximos en enero-febrero 2005 (CPUE de 21.82 y 22.18, puérulos/colector/mes, respectivamente), y mínimos en mayo y octubre de 2004. La abundancia de postlarvas de P. argus en el estudio es comparada con áreas que soportan importantes pesquerías, p. ej. México. La mayoría de las postlarvas (1027 ind.) fueron colectadas durante el cuarto creciente lunar, los restante puerulos (880 ind.) se obtuvieron en luna nueva. Estos resultados, en general, son consistentes con los encontrados para P. argus en el mar Caribe. Basados en estos resultados, se recomienda la introducción de un programa de monitoreo a nivel local o regional, estudiar los patrones de migración y distribución de la langosta espinosa, y evaluar la introducción de refugios artificiales para P. argus.

Freshwater crabs are an important component of the fauna of limnic environments, and out of the two true freshwater crab families present in the Neotropics, Pseudothelphusidae is the most diverse. Considering the lack of information regarding reproductive features of neotropical freshwater crabs, we studied, for the first time, the fecundity and the presence of juveniles carried by females of two pseudothelphusids from the Amazon region - Kingsleya latifrons (Randall, 1840) and Kingsleya ytupora Magalhães, 1986 - and one from Central America - Potamocarcinus magnus (Rathbun, 1896). The two Kingsleya species produced relatively few (56-114) and large eggs (1.9-3.7 mm), typical for species with an abbreviated or direct development. Recently produced eggs were substantially larger in K. latifrons (mean 2.83 mm) when compared to those of K. ytupora (mean 1.87 mm); however, at the end of the embryogenesis, mean egg diameter was similar in both species. Therefore, it is assumed that hatchlings in both species should have a similar size. A brief description of attached juveniles of K. ytupora is provided. The number of juveniles varied between 30 (K. ytupora) and 179 (P. magnus); two size groups of juveniles were found, which indicates that the offspring cling to their mother for a prolonged period of time. There was no significant loss of eggs and juveniles; it is assumed that parental care diminishes the loss of their offspring. We compiled the available information of reproductive aspects from freshwater crabs: egg diameter was in the range of 2-3 mm, independent of female size and fecundity, and reported egg number varied between 9 and 417 eggs.