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Atualmente não existe um projeto de música que pode ser implementado de maneira geral no ambiente intermareal. No presente estudio se propõem modificações a um método tradicional e se desmistificam as diferenças em suas estimativas. A través de um registro fotográfico, o método permite censor com rapidez e mais detalhes da composição da comunidade macrobentónica considerando a heterogeneidade do sustrato. Esto es relevante, principalmente porque se trabaja na franja inferior e se dispone de poco tiempo. A comparação dos métodos de mestre levou a cabo em uma praia rocosa do intermareal, na Ilha de Guadalupe, no Pacífico Nororiental Mexicano. A modificação do método tradicional permitiu censor e registrar valores de riqueza de espécies, abundância e diversidade de Shannon. De acuerdo a la prueba de Wilcoxon

White spot syndrome virus (WSSV) has a worldwide distribution and is considered one of the most pathogenic and devastating viruses to the shrimp industry. A few studies have explored the effect of WSSV on shrimp acclimated to low (5 practical salinity units [psu]) or high ([40 psu) salinity conditions. In this work, we analysed the physiological response of WSSV-infected Litopenaeus vannamei juveniles that were acclimated to different salinities (5, 15, 28, 34 and 54 psu). We evaluated the osmotic response and survival of the shrimp at different times after infection (0 to 48 hours), and we followed the expression levels of a viral gene (vp664) in shrimp haemolymph using real-time PCR. Our results indicate that the susceptibility of the shrimp to the virus increased at extreme salinities (5 and 54 psu), with higher survival rates at 15 and 28 psu, which were closer to the iso-osmotic point (24.7 psu, 727.5 mOsmol/kg). Acute exposure to the virus made the haemolymph less hyperosmotic at 5 and 15 psu and less hypo-osmotic at higher salinities ([28 psu). The capacity of white shrimp to osmoregulate, and thus survive, significantly decreased following WSSV infection. According to our results, extreme salinities (5 or 54 psu) are more harmful than seawater.

Genetic connectivity was studied in two scleractinian corals, Pocillopora damicornis (branching and broadcast spawner) and Pontes panamensis (massive and brooding type), along the Pacific coast of Mexico. Allelic diversity between adults and juveniles, the latter recruited after the El Nino—Southern Oscillation (ENSO) 1997–1998 event, was determined, and level of genetic connectivity among populations was assessed. There were no significant differences in allelic diversity between adults and juveniles from the same location. Seascape spatial genetic analysis suggested two or three clusters, depending on the species: (1) Bahias de Huatulco, (2) south of the Baja California Peninsula and Bahia de Banderas, and (3) locations in the Gulf of California. The most important barrier to gene flow was detected between Bahia de Banderas and Bahias de Huatulco and corresponds with a major coastal stretch of sandy beaches and lagoons. Moderate to high gene flow was found inside and at the entrance of the Gul...

Con el objetivo de caracterizar genética y morfométricamente algunas poblaciones de Chione californiensis y C. subimbricata de las costas del Golfo de California y el Pacífico bajacaliforniano, se realizaron electroforesis de alozimas en 23 sistemas enzimáticos y análisis morfométricos con 14 caracteres de la valva izquierda. Los análisis alozímicos revelaron un grado de heterocigosidad mayor a 40% en todas las poblaciones y debido a que algunos loci se desviaron significativamente de la Ley de Hardy-Weinberg, se plantea que se encuentran en desequilibrio. El indice de fijación para las poblaciones de C. californiensis indicó poca estructuración genética (FST = 0.045, Nm = 0.363) debido a que el flujo genético está limitado por la ubicación y las condiciones geográficas de las localidades en donde se recolectaron las poblaciones estudiadas. La distancia genética de Nei agrupó a las dos poblaciones más sureñas de C. californiensis y corroboró la relación sistemática de esta especie respecto a C. subimbricata. El análisis morfométrico logró evidenciar diferencias intra e interpoblacionales, así como también la relación sistemática entre ambas especies. Se identificaron seis variables morfométricas que contribuyeron en mayor medida a esta diferenciación y se obtuvieron distancias morfométricas de Mahalanobis que reflejaron diferencias en la morfometría de las dos poblaciones de C. californiensis del Golfo de California y la población del Pacífico. Los resultados generados en ambos tipos de análisis respaldaron la agrupación de estas especies dentro del subgénero Chione propuesto por Keen (1971). For the genetic and morphometric characterization of three populations of Chione californiensis and one of C. subimbricata from the Pacific Baja California and Gulf of California coastlines (Mexico), allozyme electrophoresis was performed in 23 enzymatic systems and 14 morphometric characters were analyzed. The allozymic analysis indicated a heterozygosity of more than 40% in all the populations and since some loci deviated significantly from the Hardy-Weinberg law, disequilibrium is proposed. The fixation index for the populations of C. californiensis showed little genetic structure (FST = 0.045, Nm = 0.363) because gene flow is limited by the location and geographic conditions of the sites from where they were collected. Nei|00E2|??s genetic distance grouped the two southernmost populations of C. californiensis and corroborated the systematic relationship of this species with C. subimbricata. The discriminant function analysis revealed intra- and interpopulation differences, as well as the systematic relationship between both species. Six morphometric variables were identified that contributed most to this differentiation and the Mahalanobis morphometric distances indicated differences in the morphometry of the two C. californiensis populations from the Gulf of California and the population from the Pacific. The results generated by both analyses support the inclusion of these species within the subgenus Chione proposed by Keen (1971).

Desde mediados del siglo pasado Porites sverdrupi ha sido considerado como ecotipo y, por consiguiente, sinonimo de otra especie muy abundante y de amplia distribucion, P. panamensis. Sin embargo, comparaciones morfometricas a nivel corallite demuestran que las colonias de P. sverdrupi son morfologicamente distintas y por lo tanto esta constituye una especie valida. En este analisis se contaron o midieron 16 caracteres morfologicos en 72 colonias (53 de P. panamensis y 19 de P. sverdrupi) y luego fueron sometidos a un analisis discriminante. Generalmente las estructuras medidas en ambas especies se encuentran mejor desarrolladas en P. sverdrupi que en P. panamensis. Varios de los caracteres con mayor peso en las funciones discriminantes (e.g., numero de septos bifurcados, amplitud de la pared del corallite y longitud del septo dorsal) no habian sido previamente identificados como importantes, ni en el Indo-Pacifico ni en la region del Atlantico, para el reconocimiento de especies de Porites. Ademas de las diferencias a nivel corallite entre ambas especies, P. sverdrupi es unica en sus caracteristicas ecologicas, forma colonial y distribucion geografica. Porites sverdrupi has long been considered to be an ecotype of the more abundant and widespread species P. panamensis, but multivariate comparisons of corallite characteristics indicate that P. sverdrupi is morphologically distinct and thus represents a valid species. In these analyses, linear measurements and counts were made on 72 colonies of the two species (53 of P. panamensis and 19 of P. sverdrupi), and analyzed multivariately using canonical discriminant analysis. Generally, corallite characteristics of P. sverdrupi are larger in size than P. panamensis. Important characters in the discriminant function (e.g., number of bifurcate septa, wall thickness, and dorsal septum length) have not been recognized in previous studies of Porites in either the Indo-Pacific or Atlantic regions as being significant in distinguishing among poritid species. In addition to corallite characteristics, P. sverdrupi is unique in its ecological habit, colony form, and geographic distribution.

Interbreeding between two populations (Estero de Punta Banda, Baja California, Mexico (PB) and Mission Bay, California, USA (MB)) was tested using the live progeny (nauplii) of the marine calanoid copepod Acartia californiensis, in a male to female ratio of 3:1. The laboratory conditions were 18±2°C and a 12:12 h L:D cycle, during an experimental period of one week. The first filial progeny (F1) present in the replicates were used in four combinational experiments (non-hybrids: PB-PB and MB-MB, and hybrids: PB-MB and MB-PB). To investigate the production of the F2 generation, males and females were selected from F1 and 16 combinational experiments were conducted with five replicates each (non-hybrids: PBPB-PBPB and MBMB-MBMB, and hybrids: PBPB-MBMB, PBPB-PBMB, PBPB-MBPB, MBMB-PBPB, MBMB-PBMB, MBMB-MBPB, PBMB-PBPB, PBMB-MBMB, PBMB-PBMB, PBMB-MBPB, MBPB-PBPB, MBPB-MBMB, MBPB-PBMB and MBPB-MBPB). Statistical analysis for F1 showed no significant differences of the mean for live progeny between the non-hybrids and hybrids and between non-hybrids, but a significant difference between hybrids was found. For F2, the mean live progeny between non-hybrids and hybrids, between hybrids and between non-hybrids was found to be non-significant. These results show successful interbreeding between the populations studied.

The anomuran crabs are important from the biogeographic perspective because of their benthonic behavior in their adult state. For this reason, the present work summarizes the different studies developed to date on these crustaceans within the Gulf of California and reinforces the separation of the zone from others in the Province of Cortez, or Cortesiana. The Gulf of California is inhibited by seventy-eight species of anomurans, belonging to seven families and twenty-eight genera. The best represented family regarding the number of genera (eleven), species (forty-five) and endemic species (eleven) is the Porcellanidae, followed by the Diogenidae with eight genera, fifteen species and four endemic species. The Gulf of California species are distributed in three large zoogeographical groups in the Eastern Pacific, the main one being the Panamic with an intrusion to the Gulf of 69.23% of the species reported. A second important group is that of the endemic species of the Gulf, with 24.35% of the existing species. The boreal species group with intrusion to the Gulf is present with 6.41%. Within the Californian Gulf, ten different zoogeographical groups are found, which demonstrate the great complexity of anomuran distribution, a product of the evolutionary history of this interior sea. Los cangrejos anomuros son importantes desde el punto de vista biogeografico por sus habitos bentonicos en estado adulto, razon por la cual la recopilacion de los trabajos realizados hasta la fecha con estos organismos dentro del Golfo de California permiten consolidar la separacion de la zona de otras Provincias en la Provincia de Cortez o Cortesiana. El Golfo de California se encuentra habitado por 78 especies de anomuros, pertenecientes a 7 familias y 28 generos. La familia mejor representada en cuanto a numero de generos (11), especies (45) y especies endemicas (11) es Porcellanidae, seguida de Diogenidae con 8 generos, 15 especies y 4 especies endemicas. Las especies del Golfo de California estan distribuidas en tres grandes grupos zoogeograficos en el Pacifico Oriental Americano, destacandose el de las especies Panamicas con intrusion al Golfo con el 69.23% de las especies reportadas. Otro grupo importante es el de las especies endemicas del Golfo con el 24.35% de las especies presentes. El grupo de las especies boreales con intrusion al Golfo se encuentra presente con 6.41%. Dentro del Golfo de California se encuentran 10 grupos zoogeograficos diferentes lo que demuestra la gran complejidad de su distribucion, producto de la historia evolutiva de este mar interior.

This study addressed the relative contribution of sexual and asexual reproduction to the genetic composition of populations of two scleractinian corals, Pocillopora damicornis and Porites panamensis, off the west coast of mainland Mexico. Reproductive indexes showed that P. damicornis reproduced both sexually and asexually; P. panamensis reproduced sexually, but colonies with an asexual origin were also observed (10–30%). Asexual reproduction is usually attributed to fragmentation caused by hurricanes; however, no significant association between reproductive index values and frequency of hurricanes was observed for either species. Environmental conditions in the Gulf of California seem to be more favorable for sexual reproduction in both species than other parts of the west coast of Mexico. This study contributes baseline information of differences in sexual and asexual reproduction in massive and branching corals.

Genetic variation of the marine calanoid copepod Acartia californiensis Trinast was studied from two close populations, Estero de Punta Banda, Baja California (Mexico) and Mission Bay, California (USA). The study was conducted with allozymes using a vertical polyacrylamide microelectrophoresis of 11 enzymatic systems and one buffer system. Acartia californiensis presented reliable banding patterns in six systems and eight loci, from which only PGI-1 was polymorphic, with P0.95 = 0.125 in both populations. The heterozygosity observed in Estero de Punta Banda was 0.060 ± 0.060 and 0.035 ± 0.035 in Mission Bay. There was a statistically significant deficiency in heterozygosity in Mission Bay (D = -0.477) when compared to the expected Hardy-Weinberg equilibrium, but not in Estero de Punta Banda (D = -0.096). Nei’s genetic similarity (1978) between the two populations studied was 0.994, with a genetic distance of 0.006, which proves the lack of differentiation between these populations. The results showed the existence of a genetic flow which was very likely established by a passive dispersal of diapause (resting) eggs that this species produces. They are very likely carried inward and outward by the tidal flux and reflux, and transported South by the California Current and north by Davidson’s Coastal Countercurrent. The polymorphism and heterozygosity of the A. californiensis populations studied here are among the lowest when compared to other genetically characterized copepods. This is the first study conducted on the genetic variation of a calanoid copepod confined to estuarine waters or coastal lagoons using allozymes. A broader study is needed that covers a greater number of populations (locations) and loci.

1. 1. Air- and freeze-drying caused an approximately 70% loss of total lipids, while freezing left unchanged the proximate composition of the two diatoms Chaetoceros sp. and Phaeodactylum tricornutum . 2. 2. Loss of total organics after two months of storage was approximately 20% for air- and freeze-dried algae, but lower (10 and 5% for Phaeodactylum tricornutum and Chaetoceros sp., respectively) in the samples stored in a commercial freezer. 3. 3. The amino acid profiles are similar to those generally reported for algal single-cell protein. Both algae may be considered a good source of dietary protein for aquaculture since they contain all the amino acids considered essential for fish and shrimp, including methionine. 4. 4. Short-chain (14 and 16 C) fatty acids are 90% or more in Chaetoceros , while Phaeodactylum has more than 30% of 18 to 22 C. Unsaturates are approximately 50% for Chaetoceros and vary between 44 and 63% in Phaeodactylum , depending on preservation and storage. 5. 5. Storage caused an increase in the percentages of the essential fatty acids 18:2 and 18:3.

Se caracteriza biológica y bioquímicamente poblaciones de Artemia franciscana encontradas en Baja California, México. Las cepas de Artemia franciscana analizadas comparativamente provienen (1) del Centro de Referencia de Artemia (CRA, Ghent, Bélgica) la especie franciscana (San Francisco Bay); (2) de la compañía San Francisco Bay Brand (lote 3044) otra cepa de la especie franciscana; (3) una cepa de Yavaros, Sonora, también de la misma especie; y (4) de San José, Baja California, dos muestras de poblaciones sin estudiar hasta el momento. El análisis integral, que por primera vez se realiza a un conjunto de poblaciones, demuestra en la caracterización biológica y en la determinación del grado de diferenciación interpoblacional. Según los análisis morfológicos y biométricos, las poblaciones tienen características propias pero sin alejarse de los caracteres de la especie franciscana. No se observan diferencias en la velocidad .de crecimiento intra e interpoblacional, sin embargo, se detectan diferencias en los valores de K obtenidos por medio de la ecuación de crecimiento de von Bertalanffy. Estas disimilitudes posiblemente se atribuyen a las adaptaciones fisiológicas alcanzadas por las distintas cepas a su medio natural. Los experimentos de hibridación no confirmaron aislamiento reproductivo, pero existe deterioro del vigor híbrido en los cruzamientos con los machos de una de las poblaciones de San José. Los análisis electroforéticos de nueve sistemas enzimáticos reveló un polimorfismo proteínico promedio de P

1. 1. Whole cysts of Artemia franciscana from San Francisco (USA), San Francisco Bay Brand (USA), Baja California (Mexico) and Sonora (Mexico) were analysed to describe their biochemical composition and nutritional values. 2. 2. Proteins, lipids, carbohydrates, ashes and moisture on cysts were determined. 3. 3. The total amount of lipids and proteins were subsequently analysed in order to quantify the fatty acids and amino acids, respectively. 4. 4. The results indicate differences among strains. 5. 5. Comments are made on the possible use of Mexican strains as food for aquaculture.

En el presente estudio se analiza y discute si distintas condiciones de cultivo pueden inducir a Artemia franciscana del Gran Lago Salado (Utah, EE.UU.) a mostrar diferencias genéticas, y si estas variaciones estan relacionadas con características fenotípicas de importancia acuicultural como son las tallas finales alcanzadas y la composición bioquímica, dentro de una misma cohorte. Se empleó la técnica de electroforesis en gel de almidón para analizar la variabilidad alélica de cuatro loci polimórficos: leucin-aminopeptidasa-2 (Lap-2); leucin-aminopeptidasa-3 (Lap-3); fosfoglucomutasa (Pgin) y fosfoglucosa-isomerasa (Pgi) en A. franciscana cultivada en ocho condiciones experimentales diferentes. Los organismos analizados se cultivaron hasta el estado adulto bajo un diseño experimental de 2 x 2 x 2 (22 y 30 ºC; 30 y 60 %o de salinidad, y como alimento se empleó Dunaliella sp. viva y Spirulina sp. seca comercial). Bajo la hipótesis de que no existe variación alélica significativa a corto plazo en una misma población mantenida en diferentes condiciones experimentales, se encontró que los valores promedio de heterocigosis observada (Ho) varían de 0.135 a 0.388. Las frecuencias alélicas de Lap-2A varían de 0.757 a 0.948; de Lap-3A de 0.686 a 0.862; de Pgm-IA de 0.391 a 1.000; y de Pgi-IA de 0.5 a 0.729. De los resultados obtenidos, se observa una variación alélica importante en función de las condiciones de cultivo. Al aplicar la prueba exacta de Fisher, empleando tablas de contingencia, se encontró que existen diferencias significativas (a=0.05) en las frecuencias alélicas en cada locus analizado y, por lo tanto, se rechaza la hipótesis de la independencia entre los tratamientos y la composición alélicas por locus. Sin embargo, la prueba de Tukey de no aditividad e interactivo del análisis multifactorial, que se empleó para analizar si existe un efecto sinergético de los factores y la composición alélica por locus, demostró que no existen diferencias significativas por alguno de los factores ni por la interacción entre éstos y, por lo tanto, ser determinante en la variación alélica observada. La variación alélica presente en el locus lap parece indicar, como se ha reportado por otros autores, que tiene una función específica en la osmorregulación a diferentes salinidades y temperaturas al igual que Pgm y Pgi, que intervienen en la transformación de la glucosa. Se analizó, además, la composición bioquímica de A . .franciscana determinandose el contenido de proteínas, lípidos y carbohidratos por los métodos analíticos estándar, tanto de los organismos cultivados como de las dietas suministradas. Los resultados demuestran una gran variabilidad en la composición bioquímica de A.nciscana, no sólo debida a la calidad de la dieta que se proporcionó, sino también a un efecto producido por la temperatura y la salinidad. En relación al crecimiento, se observó que las mayores longitudes totales, así como las longitudes del tórax, del abdomen y las razones longitud total/tórax y longitud total/abdomen, corresponden, en la mayoría de los casos, a los organismos cultivados en condiciones de salinidad baja. Al integrar los diferentes aspectos de este estudio, se observa que los grados de heterocigosis observada promedio de los cuatro loci no mostraron una relación aparente con las longitudes totales, velocidades de crecimiento ni con el perfil bioquímico. Sin embargo, se encontró una relación positiva de los valores de heterocigosis con la temperatura. En este estudio se demuestra que existe variabilidad en loci específicos, en una misma población, en diferentes ambientes, con lo cual se enfatiza la necesidad de tener precauciones al analizar la información genética de poblaciones naturales a traves del tiempo. En el aspecto acuicultura!, los resultados de este estudio son de gran utilidad porque se pueden obtener diferentes perfiles nutricionales y morfológicos en A . .franciscana, los cuales pueden ser aprovechados en las dietas de los cultivos de peces y camarones según sus necesidades. In the present study, it is analysed and discussed whether different culture conditions can induce genetic differences in Artemiafranciscana from Great Salt Lake (Utah, USA), and whether these variations are related to phenotypic characteristics of aquacultural importance such as final sizes and biochemical composition, within a same cohort. The starch gel electrophoresis was used to analyse the allelic variation of four polymorphic loci: leucin-aminopetidase-2 (Lap-2); leucinaminopeptidase-3 (lap-3); phosphoglucomutase (Pgm) and phosphoglucose-isomerase (Pgi) in A. franciscana cultured in eight different experimental conditions. The analysed organisms were cultured to adult stage under an experimental design of 2 X 2 X 2 (22 and 30 º C; salinity 30 and 60 %o and live Dunalliela sp. and dry commercial Spirulina sp. as nutriment). Under the hypothesis that there is no short term significant allelic variation in one same population maintained in different experimental conditions, it was found that the average values of observed heterozygosity (Ho) vary from 0.135 to 0.388. The allelic frequencies of Lap-2A vary from 0.757 to 0.948; of Lap-3A from 0.686 to 0.862; of Pgi-1 from 0.391 to 1.000 and Pgi-lA from 0.5 to 0.729. The results obtained show an important allelic variation as a function of culture conditions. When applying Fisher's exact test, using contingency tables, the existence of significant differences (a= 0.05) were found in the allelic frequencies in each locus. Therefore, the hypothesis of independence among treatments and allelic composition by locus, is rejected. However, Tukey's test of no aditivity and interactive of the multifactorial analysis, which was used to analyse if there is a synergetic effect of the factors and the allelic composition by locus, proved that there are no significant differences by any of the factors nor by the interaction among them and, therefore, proved to be determinant in the observed allelic variation. The allelic variation present in the Lap locus seems to indicate, as has been reported by other authors, that it has a specific function in the osmoregulation at different salinities and temperatures, as well as Pgm and Pgi, which take part in the transformation of glucose. The biochemical composition of the cultured organisms as well as the provided diets was analysed by standard analytic methods, determining the protein, lipid and carbohydrate contents. The results prove a great variability in the biochemical composition of A. franciscana, not only due to the quality of the furnished diet, but also due to an effect produced by temperature and salinity. In the majority of the cases, it was observed that the greater total length/thorax and total length/abdomen, correspond to the organisms cultured under low salinity conditions. When integrating the different aspects of this study, it is seen that the average degrees heterozygosity observed of the four loci did not show an apparent relationship with total length, growth velocities, or with the biochemical profile. However, a positive relationship of the values of heterozygosity with temperature was found. This study proves that there is variability in specific locus, in one same population, under different environments, which emphasizes the necessity of having precautions when analysing the genetic information of natural populations through time. In the aquacultural aspect, the results of this study are of great use because it is possible to obtain different nutritional and morphological profiles in A. franciscana, which can be used to the greatest advantage in diets for fish and shrimp culture, according to their necessities.