Repositório RCAAP

Abstract We describe a new species of freshwater crab, Aegla chilota, from two small streams at Yaldad Bay, in the southern end of Chiloé Island, western Patagonia. The new taxon is distinguished from the remaining Chilean species of Aegla Leach, 1820 by the following morphological diagnostic features: rostrum neatly triangular, short, scarcely surpassing eyes; orbital sinus wide, shallow, limited by tiny extra-orbital spine and wide extra-orbital sinus; carpal lobe prominent, triangular, tipped by at least two coalescent acute conical scales; second abdominal epimeron little produced, armed with acute scale; telson plate roughly pentagonal, with functional median suture. Molecular phylogenetic analyses also support the separation and diagnosis of A. chilota from its sister taxon, A. hueicollensis Jara and Palacios, 1999. The type locality for A. chilota n. sp. is a small river that drains a small hilly portion of the south-eastern coast of Chiloé Island; the other river in which the species was found is isolated from the type locality by the Yaldad Bay into which both rivers drain.

ABSTRACT The objective of this study was to describe the morphology of Clibanarius antillensis Stimpson, 1859 megalopae collected in the vicinity of Isla Sacrificios, Mexico, and compare it to previous descriptions originated from Brazilian and Panamanian specimens raised in laboratory conditions. We found four meristic differences between the Brazilian and the Panamanian and Mexican populations with the Brazilian population: the outer flagellum of antennule in the Panamanian and Mexican populations has more aesthetascs on the second, third, and fourth segments of the outer flagellum (0, 6, 5, 3, 0) than the Brazilian population (0, 4, 4, 2, 0); the maxilla has more setae on the scaphognathite in the Brazilian specimens (70) than in the Mexican and Panamanian specimens (49-62); the crista dentata of the third maxilliped is formed by only three denticles in the Brazilian specimens, while 4 or 6 denticles form the same structure in the Panamanian and Mexican populations; there are fewer number of setae on the endopod of the uropod in the Brazilian population. The differences may be explained by intraspecific variation.

Abstract Based on an updated checklist of the benthic caridean shrimp fauna of the Eastern Tropical Pacific (ETP), we analyzed their large-scale species richness distribution patterns using a grid approximation. Caridean fauna is composed of 183 species belonging to 67 genera and 18 families. Alpheidae, Palaemonidae and Thoridae contributed largely to species richness. Alpheus and Synalpheus were the most diverse genera. Most species (24%) have a narrow distribution inhabiting a single grid, and as many as 135 are restricted to < 5 grids. Mexico has the largest richness (130) besides Ecuador (98) and Panama (75). Richness among grids varies largely; overall, it is larger around Galapagos and Panama, Colombia, Costa Rica and the Gulf of California. There was a meaningful correlation between a proxy of sampling intensity and richness, suggesting that along with habitat heterogeneity or large-scale evolutionary processes currently invoked as richness drivers, the pattern can also be related to differences in research efforts. Exponential fitting and Chao2 index suggest that the caridean faunal inventory from the ETP is still far from being complete. Overall, the results call for a more thoughtful and systematic sampling scheme in order to get information from poorly sampled environments and areas in the ETP.

Abstract A series of specimens of the fish external parasite Rocinella murilloi Brusca and Iverson, 1985, is reported from 12 localities off western Mexico. These records are the first for southwestern Mexico (four) and add six new localities off the west coast of the Baja California Peninsula where the species was known from a single record. The specimens were recovered from bottom-operated nets, between 700 and 1235 m, slightly shallower than previous records. Environmental conditions confirm the presence of R. murilloi below the core of the Oxygen Minimum Zone, and this species appears to be highly tolerant to moderate to severe hypoxic conditions. General distribution of the species in the eastern Pacific is presented.

ABSTRACT A checklist of the order Mysida from Pulau Tinggi, Sultan Iskandar Marine Park, Johor, Malaysia is presented. With the aid of an epibenthic sledge, a total number of 9,239 mysids were collected during years 2012-2013 from two fixed stations of seagrass bed in Pulau Tinggi. So far there are 13 species, 10 genera, and 6 subfamilies of mysids. Of these, one species Siriella media Hansen, 1910 is recorded as new to Pulau Tinggi. The checklist presented herein includes the reference to each species’ original description, type locality, information on geographical distribution.

Abstract All species of Brazilian terrestrial isopod known up to date, including references and distribution information, are listed. The list comprises 189 valid species, 135 of which are endemic to the country, 22 are recorded also from other countries in the Americas, 20 are introduced, and 12 have circumtropical or pantropical distributions.

Abstract Caprellid amphipods are common crustaceans at Sargassum beds of southeastern Brazil and constitute an important link between primary producers and marine consumers. The goal of this study is to evaluate population and reproductive biology of two caprellid species: Paracaprella tenuis Mayer, 1903 and Pseudaeginella montoucheti Quitete, 1971. Sargassum cymosum Agardh, 1820 samples were collected monthly between October 2010 and September 2011 in a rock shore in southeastern Brazil. The caprellids were identified, counted, measured and classified as males, immature females, sexually mature females, ovigerous females and juveniles. Eggs were counted and measured. Higher densities of P. tenuis and P. montoucheti were found mainly in winter and lower densities in fall and summer. Density variation is probably related to organic matter supply and substrate availability. Both species showed continuous reproduction with reproductive peaks. Pseudaeginella montoucheti larger egg volume indicates a longer incubation period. The egg volume was directly related to female size. The number of eggs was weakly related to female size, indicating that fecundity may be driven by other factors, such as the physiological conditions. Sex ratio deviated for males suggests a higher longevity of males. The present study highlighted important data of two caprellids species that occur in algal beds of different regions.

Abstract Trawls from the Bay of Bengal obtained material of a new species of the goneplacid crab, Carcinoplax mistio, the sixth species of the genus known from India. The new species superficially resembles C. purpurea Rathbun, 1914, and C. sinica Chen, 1984, from the western Pacific. Records of C. sinica from the Persian Gulf are also here referred to the new species. Carcinoplax mistio n. sp. differs from its closest congeners mainly in the form of the carapace, anterolateral armature, proportions of the ambulatory legs and structure of the male pleon.

Abstract During exploratory trips conducted between August and December 2016, six shrimps, found in association with the crinoid Nemaster grandis A.H. Clark, 1909, ere collected in Chichiriviche de la Costa, Vargas State (Venezuela). A photographic record of the crinoids and the shrimps was conducted in situ. Shrimps were preserved in ethyl alcohol 90% and carried to the Laboratorio de Carcinología de la Universidad de Oriente, Núcleo Nueva Esparta. Once in the laboratory, the shrimps were taxonomically described and sexed. Shrimps were identified as Periclimenes crinoidalis Chace, 1969, constituting the first record of this species in Venezuelan waters. These findings also expand the known distribution range for the crinoid N. grandis in Venezuela, where the species exhibits two morphotypes, one of them not previously described. Additionally, a table with the species of decapods found associated with echinoderms in Venezuela is provided.

Abstract We aimed to analyze the crustacean bycatch from the Xiphopenaeus kroyeri fishery in the Santa Catarina State and compare the bycatch’s biomass to that of the target species. Shrimp and environmental factors were sampled monthly from July 2010 through June 2011. For each crustacean species, we calculated the number of individuals, the relative abundance and the occurrence frequency. The relative abundance was classified as very abundant (Va), abundant (Ab) or low abundance (La), while the occurrence frequency was labeled continuous (Co), accessory (Ac) or accidental (Ad). We observed a total richness of 28 species, which is considered high for a subtropical region. Brachyura was the most frequent taxon (74%) followed by Penaeiodea (18%). Five species were considered Va (Arenaeus cribrarius, Callinectes danae, C. ornatus, Isochelis sawayai and Pleoticus muelleri), and eight species were considered Co (A. cribrarius, C. danae, C. ornatus, Farfantepenaeus paulensis, Hepatus pudibundus, Libinia spinosa, Litopenaeus schmitti and Sicyonia dorsalis), suggesting that the studied environment is heterogeneous and provides a variety of microhabitats, enabling many species to coexist. Therefore, the high species richness observed demonstrates the ecological importance of this region and thus the necessity of strategies aiming to minimize the impacts caused by trawling fisheries.

Abstract A series of specimens of Malacoplax californiensis (Lockington, 1877) is reported from the Gulf of California, significantly increasing the known localities for the otherwise rarely reported species from 3 to 12. Depth range is increased to 110‒114 m on the continental shelf. Environmental conditions associated with the crabs were: 12.4‒27.0°C; 1.9‒5.0 ml/l O2; 58‒98% sandy sediments. Males and females were sexually distinct even at small sizes (4.2 mm and 3.5 mm CW, respectively). Two small specimens were infested with a rhizocephalan, a condition not reported previously for this species of panopeid.

Abstract Body fouling has been reduced by grooming behaviors. In decapods, grooming has been focused on gills, sensory structures, and jointed appendages. In this study, grooming behaviors of the spider crab, Libinia dubia H. Milne-Edwards, 1834, were examined; this brachyuran crab decorates and camouflages body regions by attaching materials onto hooked setae. The relationship between grooming and these camouflaged body regions was unknown. Six observational and experimental studies examined the grooming frequency, duration of grooming behaviors, body regions groomed, variance of these behaviors in the presence of another individual, and the efficiency of these grooming behaviors at removing gill fouling. Sensory and respiratory structures were groomed most frequently and for the longest duration, not body regions with decorations and hooked setae. Crabs in isolation exhibited the highest grooming time budget (5.22%). The presence of another conspecific decreased the grooming time budget (0.67%), and primary actions (e.g., fighting, displaying, mating) became priority. Ablation of a gill-grooming appendage did not impact fouling on gills. Grooming as a secondary action was supported. Reasons for not grooming body regions with hooked setae were discussed. Spider crabs had a lower time budget for grooming compared to most decapods, but similar to another brachyuran.

ABSTRACT Isopods consume feces in laboratory conditions. We investigated the effects of coprophagy on food consumption and assimilation and on isopod biomass to determine the best methodological design for feeding performance experiments. We used three species of isopods representing different eco-morphological groups and two leaves with different nitrogen content. We tested three treatments: (1) free access to feces; (2) periodic removal of feces and (3) net acting as a barrier to the feces. We did not find significant difference in any isopod or leaf species for consumption rate. Assimilation efficiency did not differ significantly for any isopod or leaf either. Only growth rate was significantly different, but only for the species Atlantoscia floridana (Van Name, 1940) with the leaf Machaerium stipitatum, and it may be due to the short duration of experiments and the isopods’ susceptibility to environmental changes. Thus, we recommend the treatment access to study consumption and growth rates since it does not require any special material or extra time. If the focus is assimilation efficiency, we suggest the treatment removal because it provides more accurate values. Furthermore, more fragile species such as A. floridana require larger sample number and/or longer experiment duration for more reliable data analyses.

Abstract The moult cycle of crustaceans is continuous and during different stages of this cycle, physiological, biochemical and morphological changes occur. Therefore, understanding the different stages of the moult cycle in the target species becomes critical for a wide range of biological studies. Here we describe the natural cycle changes in the freshwater shrimp Palaemon argentinus and identify two new substages of post-moult, B1 and B2, that are substages occurring before the intermoult, a stage widely used in crustacean studies. Furthermore, we present a more detailed description of stages already known, describing modifications of the structures and its presence or absence in each stage, in conjunction with explanatory pictures. We also indicate the duration for each stage of the cycle, thus expanding our knowledge of the moult cycle and setogenesis for P. argentinus.

Abstract The Indo-Pacific swimming crab Charybdis hellerii (A. Milne-Edwards, 1867) is native to the Indo-Pacific Ocean, and occurs as an invasive species along the Eastern American coast, where it was probably introduced in ballast water. The present study evaluated the osmoregulation and salinity tolerance of C. hellerii in Paranaguá Bay, Paraná, Brazil, an estuary under the constant threat of introduction of non-native species. The crabs were abruptly submitted to salinities of 10, 20, 30 (control), and 40 PSU for 24h. Hemolymph osmolality showed either an increase or a decrease following the changes in water salinity, presenting a pattern of hyper-osmoconformation. Muscle water content was stable at salinities from 20 to 40 PSU, and increased after exposure to 10 PSU indicating cellular swelling. At 10 PSU a physiological limit was reached, indicated by the failure of the capacity to regulate tissue water content. Although adult C. hellerii tolerate a wide range of salinities for 24 h, its osmoregulatory ability indicates a possible advantage for its establishment in estuarine waters with salinities <20 PSU. The salinity tolerance and osmoregulatory data are important basic information to be used in models to predict and prevent the invasion of the species into new areas of the Neotropics.

Abstract The rare raninid crab Umalia trirufomaculata (Davie and Short, 1989) is recorded from India for the first time. It is redescribed and compared at length with the related but poorly known U. misakiensis (Sakai, 1937) on the basis of a good series of specimens from the Philippines. Some of the supposed differences which have been documented between the two taxa (e.g., carapace proportions and features of the cheliped) are not valid; while new distinguishing characters associated with the male pleon and gonopods are observed.

Abstract Mysidopsis gemina n. sp. is described from protected and exposed beach habitats in the provinces of Puntarenas and Guanacaste on the northern Pacific coast of Costa Rica. Morphologically, M. gemina most closely resembles M. furca Bowman, 1957 known from the Atlantic and Gulf Coasts of North America. Both these species are unique within the genus by their distinctively sexually dimorphic telsons. The new Costa Rican species can be distinguished from M. furca and other species of Mysidopsis by a combination of having a male with biarticulated endopods on the first pleopods and pleopods 2-5 with large plate-like pseudopodia (exites). The occurrence of these characters and morphological features within the subfamily Leptomysinae is discussed.

Abstract Many monitoring studies use marking techniques to obtain dispersal data on individuals. Marking procedures may influence the vital activities of the terrestrial isopods, such as feeding behavior. The objective of this study was to identify the efficiency of different materials for external marking of woodlice and the influence on their feeding performance. Cyanoacrylate glue + glitter and nail polish were used as separate marking materials on three species: Balloniscus glaber, Benthana picta and Armadillidium vulgare. The material efficiency was compared using Kaplan-Meier curves and Log-Rank analysis. Individuals were fed with leaf discs of Machaerium stipitatum for feeding performance trials, and consumption rates were compared using ANOVA (α<0.05). There was no difference in durability between the materials used for external markings, except between marked and unmarked Benthana specimens when the observation period exceeded 15 days (Log-Rank=8.446, p=0.015). Nail polish was considered more suitable for feeding experiments. Statistical differences in consumption rates were observed only between the marked individual treatments of Benthana (ANOVA, F=7.5440, p=0.0002). These results indicate that external marking does not affect the feeding habits of the animals and suggest that this technique can be used to monitor dispersal of terrestrial isopods in field conditions for approximately 15 days.

Abstract A large number of specimens (2765) of the acorn barnacle Balanus trigonus Darwin, 1854, were observed on the spiny lobster Panulirus gracilis Streets, 1871, in western Mexico, including recently settled cypris (1019 individuals or 37%) and encrusted specimens (1746) of different sizes: <1.99 mm, 88%; 1.99 to 2.82 mm, 8%; >2.82 mm, 4%). Cypris settled predominantly on the carapace (67%), mostly on the gastric area (40%), on the left or right orbital areas (35%), on the head appendages, and on the pereiopods 103. Encrusting individuals were mostly small (84%); medium0sized specimens accounted for 11% and large for 5%. On the cephalothorax, most were observed in branchial (661) and orbital areas (240). Only 40-41 individuals were found on gastric and cardiac areas. Some individuals (246), mostly small (95%), were observed on the dorsal portion of somites. Of the encrusting individuals, 18% were dead with no clear pattern in localization, but less common (7%) on dorsal than on lateral portions (right, 18%; left, 32%). Larger specimens (up to 11 mm) were observed in other lobsters from different catches. Previous presence of Cirripedia in decapod crustaceans, size range in the material examined, settlement patterns, and growth of the barnacles are discussed.

OBJETIVO: Determinar a prevalência de fatores de risco para doença cardiovascular em funcionários do Centro de Pesquisas da Petrobras. MÉTODOS: Em estudo descritivo transversal, foram avaliados clínica e laboratorialmente, de março de 2000 e fevereiro de 2001, empregados do Centro de Pesquisas da Petrobras, tendo sido excluídos os que não compareceram à realização do exame médico periódico anual de 2000. Calculados o percentual da ocorrência dos fatores de risco e a média e o desvio padrão das variáveis bioquímicas, da pressão arterial e do índice de massa corpórea. RESULTADOS: De um total de 1.191 empregados, foram estudados 970, sendo 75,4% homens e 24,6% mulheres, com idade média de 42,2 anos. A prevalência de fatores de risco foi o sedentarismo (67,3%), o colesterol > 200 mg/dl (56,6%), o sobrepeso (42%), a obesidade (17%), a hipertensão arterial (18,2%), o tabagismo (12,4%) e o diabetes mellitus (2,5%). CONCLUSÃO: A elevada prevalência de fatores de risco para doença cardiovascular, em indivíduos jovens, alerta para a necessidade de adoção de programas de promoção de saúde e prevenção de doenças no ambiente de trabalho.