First record and geographic range extension of the coccolithophore Scyphosphaera apsteinii Lohman, 1902 (Haptophyta: Pontosphaeraceae) from the Pacific coast of Mexico

The coccolithophorid Scyphosphaera apsteinii is here reported for the first time from waters off the west coast of the Baja California Peninsula. Scypho­sphaera apsteinii is the type species of the genus Scyphosphaera and had hitherto been recorded only in the Atlantic and Indian Oceans, the Gulf of Mexico, the Mediterranean, and the Caribbean Seas. Specimens were found in samples collected in nets off Isla de Guadalupe in January 2013. This recording thus extends the geographical distribution of S. apsteinii from the Central Pacific (Hawaii) to the Eastern Pacific (NW Mexico)

Macroalgas marinas bentónicas de Isla Gudalupe, Baja California, México

Background. The last floristic survey of marine algae species from Guadalupe Island was published in the 1980s, including a summary of surveys from collections dating back to the beginning of the past century. Goals. To update the species inventory and analyze the macroalgae community on Guadalupe Island. Methods. Four sampling procedures were undertaken, during January, April, and October 2013, and May 2014, from intertidal and subtidal zones, at depths of between 10 and 18m, depending on the locality. Results. 102 species were identified as representatives of the threemain taxonomic divisions; 14 species belonging to Chlorophyta, 29 to Ochrophyta, and 59 to Rhodophyta, related to 39 families and 65 genres. Of the organisms found at a specific level, 30 are new records, 13 are taxonomically synonymous, and 59 correspond to previous registries. The Margalef index shows that the highest biologic richness occurred in May 2014, as while the highest diversity also appeared in that same month, as the Shannon-Wiener index indicates. Data were statistically evaluated with the PERMANOVA analysis, showing statistical differences between the analyzed factors(depth, season, zone, and locality), thus demonstrating high heterogeneity at the localities, mainly between the northern and western areas of the island. Conclusions. Guadalupe Island has high species richness and diversity. In accordance to SIMPER analysis, the species that contribute most to the qualitative differences found in the analyzed factors are Zonaria farlowii, Jania rosea, Sargassum palmeri, Dictyopteris undulata, and Padina durvillei.Antecedentes. El último inventario florístico de algas marinas de Isla Guadalupe se publicó en la década de 1980, e incluye una recopilación de trabajos de colecciones de principios del siglo pasado. Objetivos. Realizar un inventario y un análisis actualizado de la comunidad de macroalgas de Isla Guadalupe. Métodos. Se efectuaron cuatro muestreos durante los meses de enero, abril y octubre del 2013 y mayo del 2014, en la zona intermareal y en la submareal, a 10 y 18 m de profundidad, dependiendo de la localidad. Resultados. En total se determinaron 102 especies, entre las que se encuentran representantes de las tres principales Divisiones taxonómicas: 14 especies de la División Chlorophyta, 29 especies de la División Ochrophyta y 59 especies de la División Rhodophyta, las cuales se relacionan con 39 familias y 65 géneros. De los organismos determinados a nivel específico, 30 corresponden a nuevos registros, 13 con sinonimia taxonómica y 59 especies están previamente registradas. De acuerdo con el índice de Margalef, durante mayo del 2014 se presentó la mayor riqueza biológica, en este mismo periodo, según el índice de Shannon-Wiener, se encontró una mayor diversidad. Los datos se analizaron estadísticamente con el análisis PERMANOVA, el cual mostró diferencias significativas entre los factores examinados de profundidad, temporada, zona y localidad de muestreo, lo que indica una alta heterogeneidad entre las localidades, principalmente entre la zona norte y la oeste de la isla. Conclusiones. Isla Guadalupepresenta una gran riqueza y diversidad biológica. De acuerdo con el análisis SIMPER, las especies que más contribuyen a las diferencias cualitativas de los factores analizados son Zonaria farlowii, Jania rosea, Sargassum palmeri, Dictyopteris undulata y Padina durvillei

Rhodolith Bed Composition in the Southwestern Gulf of California, Mexico

The composition of rhodolith beds, relative abundance of species and growth-forms, was evaluated in relation to a depth gradient and substratum along the southwestern Gulf of California. Replicate transects were established in twelve rhodolith beds to evaluate the species and growth form distribution in relation to depth (2-7, 7-12 and 12-20 m) and habitat (sand vs. rock). Four species with four growth-forms were determined: Lithophyllum margaritae which ranged in growth-form from fruticose, fructifoliose to foliose; Lithothamnion muelleri where the growthform range was lumpy to fruticose; in both Neogoniolithon trichotomum and Mesophyllum engelhartii where only fruticose growth-form was observed. Lithophyllum margaritae was the most abundant species in relation to depth in the sandy habitat and Lithothamnion muelleri was dominant in the shallow rocky areas. The presence of N. trichotomum was limited to shallow sandy beds and M. engelhartii was limited to the deeper areas. Growth-forms also showed a variation with depth and substrata, in where fruticose forms dominate in sandy areas, lumpy forms dominate in rocky habitats and foliose forms were more abundant in the deeper areas. The differences in the abundance of each species and growth form might be explained by a combination of biological features; growth rate, density of reproductive structures and calcification rate in relation to environmental features such substrate type (rock vs. sand), water motion and light

Producción y propiedades de alginato de Sargassum sinicola (Setchell y gardner) y su aplicación en inmovilización celular

IMPRESO Y PD