Abstract in English:This study evaluated the spatial-temporal distribution of the abundance of Caridean and Penaeid shrimps during the period of two years in the coastal region of Macaé, state of Rio de Janeiro, southeastern Brazil, using ecological indices (Shannon-Wiener diversity and Pielou's equitability). Monthly samples were carried out from March 2008 to February 2010 distributed in six stations located Inner Area (5, 10 and 15 m depth) and Outer Area (25, 35 and 45 m depth) using a commercial fishery boat equipped with an otter-trawl net. Water samples were taken for determination of temperature and salinity, and sediment samples for determination of texture and organic matter content. Ten species of Decapoda, including Penaeids and Carideans, have been identified, from a total of 49.941 collected individuals. There was a strong correlation between Penaeid and Caridean shrimps abundance and the bottom temperature and sediment. It could be inferred that Artemesia longinaris acted as a keystone species regulating the shrimps community in the coast of Macaé, given that both species diversity and equitability were controlled by the migratory events of A. longinaris following the variations in temperature caused by the SACW. These results provide as a basis for management actions to prevent significant losses of population stocks since it is an important marine area considering of its peculiar relevance to the fishery.
Abstract in English:This study aimed to describe the population structure of the Amazon shrimp Macrobrachium amazonicum, as well as their relative growth between the length of the cephalothorax and the total length, and between the length of the cephalothorax and the total mass of shrimps of a fluvial-estuarine plain in the State of Pará. Shrimps were sampled monthly from August 2006 to July 2007, using trawl nets, taking three replicates at each site (Arapiranga and Mosqueiro) per month, totaling 72 replicates. We caught 5,510 specimens, being 90.90% from Arapiranga Island and 9.1% from Mosqueiro Island. The highest densities occurred in July (1.33 individuals/m²), at the beginning of the dry season and in December (1.66 individuals/m²), at the beginning of the rainy season. The morphometric analysis for separate and grouped sexes resulted in negative and positive allometric growth. Ovigerous females were observed in all months, indicating continuous reproduction and the majority (67.81%) was caught during the less rainy season. The abundance and continuous reproduction of M. amazonicum show that this estuary offers conditions for the proper development of this population.
Abstract in English:Zooplankton plays key roles in structuring interactions in aquatic communities but often remain undescribed in many water systems. This paper reports seventeen species of the Cladocera (Crustacea: Branchiopoda) from Laguna de Navío Quebrado, all of them new records for La Guajira Department, Colombia. The Cladocera assemblages include mostly the Neotropical taxa associated with vegetation. This paper also serves as the first compilation of the data on the Cladocera of this region and includes brief remarks, descriptions and illustrations of some species with additional notes on their distribution.
Abstract in English:A total of six species of pelagic shrimps were collected during the TALUD XIV cruise aboard the R/V "El Puma", in the northern Gulf of California, in April 2011, including two species of Dendrobranchiata [Eusergestes similis (Hansen, 1903) and Sergia phorca (Burkenroad, 1940)], and three species of Caridea [Pasiphaea americana Faxon, 1893, P. emarginata Rathbun 1902, and P. pacifica Rathbun, 1902]. Additional specimens of the previously reported Maryprocessa pippinae (Wicksten & Méndez, 1985) were also found among the samples. Most frequently collected species were P. americana (50% of total) and P. pacifica (36.6%). Most numerous species in the samples were P. pacifica, P. americana and E. similis. Some minor morphological differences not previously recorded in specimens of Pasiphaea pacifica collected elsewhere were detected. These differences might correspond to an intraspecific variation.
Abstract in English:Analysis of wild phyllosoma of Panulirus inflatus (Bouvier, 1895) and P. gracilis Streets, 1871 determined the morphological structures having taxonomic value for differentiation of the two species, in addition to the structures described previously. Of 54 phyllosoma, species identity was confirmed by PCR-restriction fragment length polymorphism (RFLP) on 42 P. inflatus and 4 P. gracilis, for which morphology and morphometric measurements were taken. Morphological analysis found subexopodal spines, spines at the base of pereopods 1 and 2, and the mandibles are structures of taxonomic value for differentiating the two species. Morphometric data did not allow differentiation.
Abstract in English:Three new species of Munidopsis (M. amapa and M. brasilia from Brazil, and M. bajacalifornia from California and the Galápagos Islands) are described. All are small, superficially similar to each other and from shallower depths than is typical of most of the genus. All species have a highly sculptured carapace, triangular rostrum and immovable eyestalks with prominent anterior eyespines.
Abstract in English:This paper presents details regarding the collections and records of H. strigillata in the Bay of Mazatlán, SE Gulf of California, Mexico. Samples of H. strigillata were obtained in this bay and suroundings area during different periods and deposited in the collection of UNAM, Mazatlán. Morphometric data, distribution, biological and ecological data were furnished.