Taxonomic Validity of Gymnura crebripunctata (Peters 1869) and Gymnura marmorata (Cooper 1863): a Meristic, Morphometric, and Molecular Approach.

Recent artisanal elasmobranch fishery surveys in the Gulf of California and Pacific coast of Mexico have indicated that batoids are a much moreimportant component of landings than previously estimated. Two butterflyrays, Gymnura crebripunctata and G. marmorata, are recognized in the Mexican Pacific and are among the primary elasmobranchs observed in these landings. The validity of these species was first questioned in 1928, but evidence supporting synonymy has been inconclusive. However, the primary characteristics used to distinguish the species (inter-orbital width and pre-orbital length) are known to be sexually dimorphic features in Gymnura micrura. To determine if G. crebripunctata and G. marmorataare valid species or male and female morphs of the same species, multiple analytical techniques have been applied. Heart and white muscle tissues were collected from fishery-derived specimens in the states of Sonora and Baja California Sur, Mexico. Similarity of the two species was examined through direct sequence comparison and phylogenetic analyses of approximately 445 base pairs of the mitochondrial cytochorme b locus, including other congeners as outgroups. Measurements, vertebral and spiral valve counts were obtained from and and compared to field and museum specimens. We report here on the preliminary results from these analyses

La pesca de almeja Panopea spp. en el noreste de México

In 2008 the Mexican Pacific Ocean contributed to the production of clam with 88% of national clam catch, and the Gulf of Mexico and Caribbean Sea with 12%. In the Pacific are Baja California Sur and Sinaloa, whereas Veracruz and Tabasco stand out in the zone of the Gulf and the Caribean. Baja California Sur is the principal national producer. Panopea globosa and P. generosa clam fishery in Mexico started very recently, in 2000, at first to determine its commercial viability on the east coast of Baja California, while commercial fishing started in 2004 and a year later on the west coast of Baja California and Baja California Sur. From 2002 to 2009 its catch varied between 38 and 1 959 t of live weight. In this period, the east coast of Baja California -included Alto Golfo-accounted for 41% of the capture of Baja California. During 2010 there was commercial fishing as well as experimental fishing in Baja California and Baja California Sur, while in Sonora commercial fishing had not yet started. The clams have a great demand, which creates a strong pressure for access to their capture. This combined with the limited inspection and surveillance, deficient registration, its sedentary status, its high longevity, low recovery, recruitment and growth rates may result in their overfishing. In 2007, INAPESCA proposed to the fisheries authorities a management plan for Baja California and in 2008 to determine its commercial opening in Sonora. These plans are based on resource management per bank, considering three stages: a) prospection, b) development fishing, and c) commercial fishing (the first two are fishing for research purposes). The trend of the fishery is towards an adaptive administration, there are insufficient human and monetary resources, neither follow-up nor arrangement. Some licensees hire a particular at the absence of official surveillance.En 2008 el Pacífico mexicano contribuyó a la producción de almeja con 88% y el Golfo de México y Mar Caribe con 12%. En el Pacífico destacan Baja California Sur y Sinaloa mientras que Veracruz y Tabasco sobresalen en la zona del Golfo y el Caribe. BCS es el principal productor nacional. La captura de almeja Panopea globosa y P. generosa en México inició en 2000, primero para determinar su factibilidad comercial en la costa oriental de BC, posteriormente en 2004 su pesca comercial; y un año después en la costa occidental de Baja California y en BCS. De 2002 a 2009 su producción creció de 38 a 1 959 t de peso vivo, en este periodo, la costa oriental de Baja California (incluido el Alto Golfo) aportó 41% a la captura de dicho estado. En 2010 se tuvo tanto pesca comercial como pesca de fomento en BC y BCS, mientras que en Sonora aún no se abrió comercialmente. Este recurso tiene gran demanda, lo que origina una fuerte presión que puede ocasionar su sobrepesca, aunada a las escasas inspección y vigilancia, deficiencia en su registro, a su condición sedentaria y a su historia de vida. En 2007, el INAPESCA propuso a la autoridad pesquera su plan de manejo en Baja California y en 2008 para determinar su apertura comercial en Sonora. Dichos planes, con base en la administración del recurso por banco, contemplan tres etapas: a) prospección, b) pesca de fomento y c) pesca comercial (los dos primeros corresponden a pesca para fines de investigación). La tendencia de la pesquería es hacia una administración adaptativa, no hay recursos humanos y monetarios, seguimiento, ni ordenación suficientes. Ante la ausencia de vigilancia oficial, algunos permisionarios contratan una particula

Morphological Conservation of Rays in the Genus \u3ci\u3eRhinoptera\u3c/i\u3e (Elasmobranchii, Rhinopteridae) Conceals the Occurrence of a Large Batoid, \u3ci\u3eRhinoptera brasiliensis\u3c/i\u3e Muller, in the Northern Gulf of Mexico

In 2007, three rays identified as Rhinoptera brasiliensis based on tooth series counts were captured in the northern Gulf of Mexico, a region far outside their accepted range of the coastal waters of southern Brazil. Genetic analyses confirmed that these individuals were distinct from R. bonasus, the only recognized indigenous rhinopterid in the Gulf of Mexico. Further analyses of over 250 specimens confirmed the widespread occurrence of two species in the northern Gulf of Mexico and revealed that the anomalous individuals related most closely to vouchered specimens of R. brasiliensis from Brazil. Discriminant function analyses of morphological data identified several potential discriminating characters, but the degree of overlap of the measurements and counts between the two species rendered most impractical for identification purposes. However, the shape of the supracranial fontanelle appeared to be consistently reliable in differentiating between the two species. Tooth series counts (R. bonasus = 5 to 15, R. brasiliensis = usually 7 to 13) were significantly different between the two species but exhibited considerable overlap. This is the first study to verify the occurrence of R. brasiliensis in the northern Gulf of Mexico; however, the close genetic relationships to other rhinopterid species, as well as the morphological similarity of the group as a whole, require additional research