A new species of <i>Parthenope</i> Weber (Crustacea: Brachyura: Parthenopidae) from the Pacifc coast of Mexico

A new species of Parthenopidae from the East Pacific belonging to the genus Parthenope Weber is described and illustrated. Parthenope johngarthi n. sp. was collected along the west coast of Mexico, off the coast of Jalisco and Colima. Parthenope johngarthi is readily distinguished from species of other genera of Parthenopidae from the East Pacific by the shape of the tuberculate carapace, the relative lenght and shape of the chelipeds, and the shape and relative size of segments of walking legs. It is closely related to P. exilipes (Rathbun, 1893) but differs from the latter by its slender and almost smooth walking legs, its slender and less densely tuberculate chelipeds, and by its almost straight, narrower rostrum. Comparison of male first gonopods from both species also indicates differences that are considered of specific value

Estudios de marcado y recaptura de especies marinas

Los resultados obtenidos del marcado y posterior recaptura de los ejemplares son una herramienta muy valiosa para contribuir a mejorar el conocimiento de la biología y ecología de una especie, examinando ciertos aspectos como son: el crecimiento, los movimientos o migraciones, la mortalidad o supervivencia, la abundancia y distribución de la especie, el hábitat y diferenciación de poblaciones o stocks. Actualmente la técnica de marcado se aplica a muchas especies, tanto terrestres como marinas, pertenecientes a diversos grupos zoológicos: peces, crustáceos, reptiles, moluscos y mamíferos. Este libro repasa algunos ejemplos de marcado de especies marinas de interés comercial. No todas las especies pueden ser marcadas, porque es necesario cumplir una serie de requisitos para poder llevar a cabo con éxito un experimento de marcado. En uno de los apartados de esta guía, se describen los distintos aspectos a tener en cuenta para obtener buenos resultados. Se describen los principales proyectos de marcado actualmente en ejecución o en marcha llevados a cabo por el Instituto Español de Oceanografía (IEO). En primer lugar, se describe brevemente la especie, su distribución, crecimiento, reproducción, alimentación, etc. A continuación, se presenta la información del marcado, es decir, campañas realizadas, número de ejemplares marcados y algunos de los resultados obtenidos hasta la fecha a partir de las recapturas disponibles. En algunas especies, los programas de marcado se llevan realizando desde hace más de 20 años, como es el caso del atún rojo, por lo que la información disponible es bastante amplia. En otros casos por el contrario como la merluza, los proyectos son relativamente recientes, no obstante los resultados son bastante interesantes y prometedores.Nowadays many different marine animals are being tagged. This book summarizes recent tagging programs carried out by the Spanish Institute of Oceanography (IEO). Although the objectives of these various studies mainly depend on the species and each project in particular, the general aim is to better understand the biology and ecology of these animals the structure and dynamics of their populations and their capacity to respond to human activities. This book provides an overview of different aspects of this technique such as a brief history of tagging, the types of tags currently used, including both conventional and electronic tags, where and how to put them on the marine animals, some recommendations regarding how to perform a tagging survey and where to go or what to do if anyone recovers a tagged fish or marine animal. The book then summarizes the main species tagged by the IEO, making a short description of their biology followed by some of the results obtained from tagging studies undertaken until now. Other applications are to know the spatial distribution (spawning or feeding areas), estimate growth parameters, mortality and survival rates, longevity, the size of the population or identifying stocks. Nowadays the advances in electronics have also open new fields such us the possibility of tracking an animal and knowing its habitat preferences and behaviour. Besides some of these tags have the capacity of recording this information during long periods and sending the data from long distances even without the need to recover the animal. Tagging activities constitute a very useful tool to improve the knowledge of many species and contribute to their management and conservation. For that reason this methodology is included in many IEO projects in which other activities like the monitoring of the fishery (landings, fishing effort, fleet characteristics, fishing areas, biological sampling, etc.) are carried out. Some projects are related with coastal pelagic fisheries including anchovy, sardine and mackerel or oceanic pelagic fisheries like tuna and billfish species and pelagic sharks. Others are focused on benthic and demersal species such as hake, black spot seabream, anglerfish, flatfish, etc. Nevertheless not all species can be tagged, as they have to survive being caught and handled before being release. For this reason, tagging techniques may not easily be applied to some species.Versión del edito

Benthic mollusc assemblage of the Agua Dulce/El Ermitaño lagoon estuarine system, Jalisco, Mexico [Asociación de moluscos bentúnicos del sistema lagunar estuarino Agua Dulce/El Ermitaño, Jalisco, México]

The malacological fauna of the Agua Dulce/El Ermitaño lagoon estuarine system was characterized and its relation to some environmental parameters determined. Five samplings were carried out in January, August, October and December 1993, and February 1994. Biological, hydrological and sediment samples were taken at seven stations in each water body of the system, located on the northern coast of the state of Jalisco (Mexico). The values of some physical and chemical parameters were recorded and differences were found between both water bodies, mainly in regard to salinity, as an average value of 27 psu was obtained for Agua Dulce lagoon and of 2 psu for El Ermitaño estuary. The qualitative analysis of the sediments showed that the system is made up of four basic types: sandy silt, clayey silt, fine to medium sand and a small part of rocky substrate. The malacological fauna was composed of two classes, Gasteropoda and Bivalvia, the first being the one that presented a greater number of species; 6,782 live organisms and 18,508 dead organisms were collected, corresponding to 17 species of gastropods and 14 bivalves. Of the 31 species collected, only 9 were found alive and some appeared in both water bodies in spite of the salinity gradient recorded in the system. Groups of representative species were identified for four types of environments (marine, &gt;25 psu; euryhaline, 10-18 psu; brackish, 5-10 psu; and freshwater, 0-5 psu). Finally, the most important species were the bivalves Tagelus longisinuatus and Mytella strigata, and the gastropods Rissoella excolpa and Bittium mexicanum, with the highest abundances of the cycle. Low diversity values were obtained (D = 1.5-1.8, Dmax = 2.5); however, they were within those recorded for tropical and subtropical coastal ecosystems

Benthic mollusc assemblage of the Agua Dulce/El Ermitaño lagoon estuarine system, Jalisco, Mexico

 The malacological fauna of the Agua Dulce/El Ermitaño lagoon estuarine system was characterized and its relation to some environmental parameters determined. Five samplings were carried out in January, August, October and December 1993, and February 1994. Biological, hydrological and sediment samples were taken at seven stations in each water body of the system, located on the northern coast of the state of Jalisco (Mexico). The values of some physical and chemical parameters were recorded and differences were found between both water bodies, mainly in regard to salinity, as an average value of 27 psu was obtained for Agua Dulce lagoon and of 2 psu for El Ermitaño estuary. The qualitative analysis of the sediments showed that the system is made up of four basic types: sandy silt, clayey silt, fine to medium sand and a small part of rocky substrate. The malacological fauna was composed of two classes, Gasteropoda and Bivalvia, the first being the one that presented a greater number of species; 6,782 live organisms and 18,508 dead organisms were collected, corresponding to 17 species of gastropods and 14 bivalves. Of the 31 species collected, only 9 were found alive and some appeared in both water bodies in spite of the salinity gradient recorded in the system. Groups of representative species were identified for four types of environments (marine, >25 psu; euryhaline, 10–18 psu; brackish, 5–10 psu; and freshwater, 0–5 psu). Finally, the most important species were the bivalves Tagelus longisinuatus and Mytella strigata, and the gastropods Rissoella excolpa and Bittium mexicanum, with the highest abundances of the cycle. Low diversity values were obtained (D = 1.5–1.8, Dmax = 2.5); however, they were within those recorded for tropical and subtropical coastal ecosystems

Benthic mollusc assemblage of the Agua Dulce/El Ermitaño lagoon estuarine system, Jalisco, Mexico [Asociación de moluscos bentónicos del sistema lagunar estuarino Agua Dulce/El Ermitaño, Jalisco, México]

The malacological fauna of the Agua Dulce/El Ermitaño lagoon estuarine system was characterized and its relation to some environmental parameters determined. Five samplings were carried out in January, August, October and December 1993, and February 1994. Biological, hydrological and sediment samples were taken at seven stations in each water body of the system, located on the northern coast of the state of Jalisco (Mexico). The values of some physical and chemical parameters were recorded and differences were found between both water bodies, mainly in regard to salinity, as an average value of 27 psu was obtained for Agua Dulce lagoon and of 2 psu for El Ermitaño estuary. The qualitative analysis of the sediments showed that the system is made up of four basic types: sandy silt, clayey silt, fine to medium sand and a small part of rocky substrate. The malacological fauna was composed of two classes, Gasteropoda and Bivalvia, the first being the one that presented a greater number of species; 6,782 live organisms and 18,508 dead organisms were collected, corresponding to 17 species of gastropods and 14 bivalves. Of the 31 species collected, only 9 were found alive and some appeared in both water bodies in spite of the salinity gradient recorded in the system. Groups of representative species were identified for four types of environments (marine, &gt;25 psu; euryhaline, 10-18 psu; brackish, 5-10 psu; and freshwater, 0-5 psu). Finally, the most important species were the bivalves Tagelus longisinuatus and Mytella strigata, and the gastropods Rissoella excolpa and Bittium mexicanum, with the highest abundances of the cycle. Low diversity values were obtained (D = 1.5-1.8, Dmax = 2.5); however, they were within those recorded for tropical and subtropical coastal ecosystems

Soft-bottom benthic macromollusks of the continental shelf off Jalisco and Colima, Mexico

Mollusks collected from soft bottoms of the continental shelf off Jalisco and Colima were analyzed. Three cruises were made during one year (1995-1996) on board the ship BIP-V. The samples were taken during half-hour trawls, in seven different localities at four different depths (20, 40, 60, 80 m). A checklist is presented that contains 92 species of mollusks, belonging to 3 classes (Gastropoda, Bivalvia and Cephalopoda) and 37 families. Five new records are obtained for Nassarius guaymasensis, Latirus mediamericanus, Chicoreus (Phyllonotus) peratus, Hexaplex nigritus and Polymesoda (Egeta) inflata, which are range extensions

Soft-bottom benthic macromollusks of the continental shelf off jalisco and colima, Mexico [Macromoluscos bentonicos de fondos blandos de la plataforma continental de jalisco y colima, Mxico]

Mollusks collected from soft bottoms of the continental shelf off Jalisco and Colima were analyzed. Three cruises were made during one year (1995-1996) on board the ship BIP-V. The samples were taken during half-hour trawls, in seven different localities at four different depths (20, 40, 60, 80 m). A checklist is presented that contains 92 species of mollusks, belonging to 3 classes (Gastropoda, Bivalvia and Cephalopoda) and 37 families. Five new records are obtained for Nassarius guaymasensis, Latirus mediamericanus, Chicoreus (Phyllonotus) peratus, Hexaplex nigritus and Polymesoda (Egeta) inflata, which are range extensions

Soft-bottom benthic macromollusks of the continental shelf off jalisco and colima, Mexico [Macromoluscos bentonicos de fondos blandos de la plataforma continental de jalisco y colima, Mxico]

Mollusks collected from soft bottoms of the continental shelf off Jalisco and Colima were analyzed. Three cruises were made during one year (1995-1996) on board the ship BIP-V. The samples were taken during half-hour trawls, in seven different localities at four different depths (20, 40, 60, 80 m). A checklist is presented that contains 92 species of mollusks, belonging to 3 classes (Gastropoda, Bivalvia and Cephalopoda) and 37 families. Five new records are obtained for Nassarius guaymasensis, Latirus mediamericanus, Chicoreus (Phyllonotus) peratus, Hexaplex nigritus and Polymesoda (Egeta) inflata, which are range extensions

Distribution and abundance of soft-bottom stomatopod crustaceans off the coast of Jalisco and Colima, Mexico

Three cruises (DEM I, DEM II, DEM III) were conducted during 1995 and 1996. Seven localities were visited during each cruise at four different depths (20, 40, 60 and 80 m), with paired shrimp trawls on the continental shelf off Jalisco and Colima, Mexico. Five genera and nine species belonging to the families Eurysquillidae, Hemisquillidae, Lysiosquillidae and Squillidae were identified. The highest richness was found on the DEM III cruise (eight species), with an average abundance of 74 ind/ha. During DEM III Squilla panamensis was the most abundant species (average = 58 ind/ha). Squilla hancocki was the most abundant on the DEM I and DEM II cruises, with 18 and 44 ind/ha, respectively. The highest abundance was observed at the 60 m depth, with temperature averages between 13.9 and 23.9°C. The highest- co-occurrence frequency (31.7%) was found between S. hancocki and S. panamensis

The vertical distribution and abundance of gastropods and bivalves from rocky beaches of Cuastecomate Bay, Jalisco. México

The vertical distribution and abundance of conspicuous gastropod and bivalve species were studied at five rocky beaches in Cuastecomate Bay, Jalisco. Sampling was done from September, 1993 through March, 1994 with 0.75 m2 quadrants placed along replicate transect lines (10 m long) in the supralittoral and mesolittoral (upper, middle and lower intertidal) zones. A total of 6 643 mollusks were collected. Gastropods dominated the samples (6 272 individuals, 44 species); the bivalves were less abundant and diverse (371 individuals, five species). Seventeen species comprised 89.8% of all individuals collected. The gastropods Nodilittorina aspera and Nerita scabricosta were the most abundant with 637.8 and 71.43 individuals/m2, respectively. The most abundant bivalves were Brachidontes adamsianus and Chloromytilus palliopunctatus with 60.7 and 61.3 individuals/m2 respectively. The abundance of gastropods decreased from the supralittoral to the lower tidal zones while the number of species increased in the same direction. The number of species of bivalves also increased from the supralittoral to the lower intertidal zone; the abundance of individuals was higher at the middle intertidal zone. Affinities between groups of species among sampling stations were identified by computing Pearson's correlation coefficient using abundance values (ind./m2) and Jaccard's dissimilarity index using species presence or absence in the lower intertidal zone. Affinity among stations was not dependent upon their vicinity but on the high dominance of few species, the occurrence of many secondary species and beach characteristics