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The occurrence of Salmonella enterica in the environment of tropical and desert regions has remained largely uninvestigated in many areas of the world, including Africa. In the present study, we investigated the presence of Salmonella spp. along 122 km of the coastline of Agadir (southern Morocco) in relation to environmental parameters. A total of 801 samples of seawater (243), marine sediment (279), and mussels (279) were collected from six sites between July 2004 and May 2008. The overall prevalence of Salmonella spp. was 7.1%, with the highest occurrence in mussels (10%), followed by sediment (6.8%) and seawater (4.1%). Only three serotypes were identified among the 57 Salmonella sp. strains isolated. S. enterica serotype Blockley represented 43.8% of all Salmonella strains and was identified in mussel and sediment samples. S. enterica serotype Kentucky (29.8%) was found almost exclusively in mussels, whereas S. enterica serotype Senftenberg (26.3%) was detected in sediment and seawater. Statistical analysis using generalized additive models identified seawater temperature, environmental temperature, rainfall, and solar radiation as significant factors associated with the presence of Salmonella. Rainfall was the only variable showing a linear positive effect on the presence of Salmonella in the sea, whereas the remaining variables showed more complex nonlinear effects. Twenty-eight (49.1%) Salmonella isolates displayed resistance to ampicillin (22 isolates), nalidixic acid (9 isolates), sulfonamide compounds (2 isolates), and tetracycline (1 isolate), with six of these isolates displaying multiple resistance to two of these antimicrobial agents. Pulsed-field gel electrophoresis analysis revealed homogenous restriction patterns within each serotype that were uncorrelated with the resistance pattern profiles.

2019. Hidden diversity under morphology-based identifications of widespread invasive species: the case of the 'well-known' hydromedusa Craspedacusta sowerbii Lankester 1880. Animal Biodiversity and Conservation, Doi: https://doi. AbstractHidden diversity under morphology-based identifications of widespread invasive species: the case of the 'wellknown' hydromedusa Craspedacusta sowerbii Lankester 1880. A relatively scarce number of morphological features available for delimiting closely related species and an increasingly worrisome scenario on Global Climate Change causing the rapid dispersion of invasive alien species can lead to the rapid spread of reports of a given species around the world. Craspedacusta sowerbii Lankester, 1880 is considered the most widespread freshwater jellyfish species and has been reported in numerous locations on all continents except Antarctica. Recently, a few medusae attributed to C. sowerbii were collected from a water reservoir (Bin El Ouidan) in Morocco, this being the first confirmed record of the species from North Africa. The morphology of these newly collected specimens agrees well with previous descriptions, but mitochondrial (Cox1 and 16S) and nuclear ITS (ITS1-5,8S-ITS2) molecular data lead to a discussion of a more complex general view concerning the number of species, synonyms and nomenclatural problems hidden behind the reports of Craspedacusta sowerbii. ResumenLa diversidad oculta en las identificaciones basadas en la morfología de especies invasoras de amplia distribución: el caso de la "bien conocida" hidromedusa Craspedacusta sowerbii Lankester 1880. El número relativamente escaso de características morfológicas utilizadas para delimitar especies estrechamente relacionadas y el panorama cada vez más preocupante en el que el cambio climático global provoca la rápida dispersión de especies exóticas invasoras pueden conducir a la difusión precipitada por todo el mundo de informes sobre una especie determinada. Craspedacusta sowerbii Lankester, 1880, que se considera la especie de medusa de agua dulce más extendida, ha sido observada en numerosos lugares en todos los continentes, excepto en la Antártida. Recientemente, se recogieron algunas medusas atribuidas a C. sowerbii en un embalse artificial (Bin El Ouidan) en Marruecos, que representaron el primer registro confirmado de la especie en el norte de África. La morfología de estos especímenes recién recolectados concuerda con las descripciones anteriores, pero los datos moleculares mitocondriales (Cox1 y 16S) y nucleares ITS (ITS1-5,8S-ITS2) suscitan un debate general más complejo con respecto al número de especies, las sinonimias y los problemas nomenclaturales ocultos tras los informes de Craspedacusta sowerbii.Hidden diversity under morphology-based identifications of widespread invasive species: the case of the 'well-known' hydromedusa Craspedacusta sowerbii Lankester 1880

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SUMMARY:The reproductive biology of the European hake (Merluccius merluccius, Linnaeus, 1758) was studied on the eastern central Atlantic Moroccan coast from November 2001 to December 2003. The sex ratio was close to 1:1 for the specimens with a total length of less than 45 cm. European hake spawned all year round, though two spawning peaks were recorded with a certain interannual variability: the first and main peak in winter and a secondary intermittent peak in summer. Length at first maturity was estimated as 28.6 cm and 33.8 cm total length for males and females, respectively. These values are closer to Mediterranean than Atlantic hake values. The mean batch fecundity was 299872 eggs ind -1 . The relative batch fecundity was estimated as 228 eggs per gram of gutted weight. Batch fecundity increased proportionally with fish length and weight. The batch fecundity of European hake in the Moroccan Atlantic area is higher than that in northern Atlantic and northwestern Mediterranean areas.Keywords: Merluccius merluccius, sex ratio, reproductive cycle, length at first maturity, fecundity.RESUMEN: Madurez y fecundidad parcial de la merluza europea (Merluccius Merluccius, Linnaeus, 1758) en el Atlántico Oriental central. -Se ha estudiado la biología reproductiva de la merluza europea (Merluccius merluccius, Linnaeus, 1758) en la zona central del Atlántico Oriental de la costa de Marruecos durante el período de noviembre de 2001 a diciembre de 2003. La proporción sexual fue cercana a 1:1 para los individuos de talla total menor de 45 cm. La merluza europea se reproduce durante todo el año. Se han detectado dos picos de puesta con una cierta variabilidad interanual: el primero y más importante en invierno y otro pico secundario intermitente en verano. La talla de primera madurez se estimó en 28.6 cm y 33.8 cm de longitud total para machos y hembras respectivamente. Estos valores son más cercanos a los observados para la merluza en el Mediterráneo que a los del Atlántico. La fecundidad parcial media fue de 299872 huevos ind -1 . La fecundidad parcial relativa se estimó en 228 huevos por gramo de hembra referido al peso eviscerado. La fecundidad parcial se incrementó proporcionalmente a la longitud y peso del pez. La fecundidad parcial de la merluza europea en el área atlán-tica de Marruecos, muestra valores más altos que en las áreas del Atlántico situadas más al norte y del NW Mediterráneo.Palabras clave: Merluccius merluccius, proporción sexual, ciclo reproductivo, talla de primera madurez, fecundidad. 2011, 447-454, Barcelona (Spain) Scientia Marina75(3) September