Marine Biodiversity in the Caribbean: Regional Estimates and Distribution Patterns

This paper provides an analysis of the distribution patterns of marine biodiversity and summarizes the major activities of the Census of Marine Life program in the Caribbean region. The coastal Caribbean region is a large marine ecosystem (LME) characterized by coral reefs, mangroves, and seagrasses, but including other environments, such as sandy beaches and rocky shores. These tropical ecosystems incorporate a high diversity of associated flora and fauna, and the nations that border the Caribbean collectively encompass a major global marine biodiversity hot spot. We analyze the state of knowledge of marine biodiversity based on the geographic distribution of georeferenced species records and regional taxonomic lists. A total of 12,046 marine species are reported in this paper for the Caribbean region. These include representatives from 31 animal phyla, two plant phyla, one group of Chromista, and three groups of Protoctista. Sampling effort has been greatest in shallow, nearshore waters, where there is relatively good coverage of species records; offshore and deep environments have been less studied. Additionally, we found that the currently accepted classification of marine ecoregions of the Caribbean did not apply for the benthic distributions of five relatively well known taxonomic groups. Coastal species richness tends to concentrate along the Antillean arc (Cuba to the southernmost Antilles) and the northern coast of South America (Venezuela – Colombia), while no pattern can be observed in the deep sea with the available data. Several factors make it impossible to determine the extent to which these distribution patterns accurately reflect the true situation for marine biodiversity in general: (1) highly localized concentrations of collecting effort and a lack of collecting in many areas and ecosystems, (2) high variability among collecting methods, (3) limited taxonomic expertise for many groups, and (4) differing levels of activity in the study of different taxa

Nuevas adiciones a la fauna de rotiferos de Venezuela

Una revision de los rotiferos presentes en las colecciones de plancton realizadas entre 1980 y 1990 en diferentes cuerpos de agua continentales del pais (lagunas, reservorios, rios, riachuelos y sabanas inundables) dio como resultato un total de 126 taxa, de los cuales 7 se mencionan por primera vez para Sur America y 23 para Venezuela. Asi mismo, se incrementa a 146 la fauna de rotiferos de las sabanas inundables de Mantecal (Edo. Apure) con la adicion de 49 taxa. Se incluyen caracteristicas de las localidades estudiadas, asi como una breve descricion e illustrationes de las especies, formas y variedades nuevas para Sur America. (Résumé d'auteur

Rotifer fauna from Venezuela

The rotifer fauna of Venezuela is analysed in the light of previously existing literature and observations, and the unpublished results of authors. A total of 268 taxa belonging to 44 genera are recorded. The genera Lecane, Brachionus and Trichocerca are the most diverse. Taxocoenosis consists of cosmopolitan (68 %), pantropical (19 %), neotropical (11 %) and neartic (2 %) taxa. The proportion of endemic taxa is comparable to other tropical regions where endemism of genus Brachionus is the highest. Only a small number of species are quite common and occur in a wide range habitats. Flooding waterbodies have the largest number of taxa. Some amazonian endemic taxa can be found up to 10° north latitude, while others are restricted to the Orinoco River Basin under this latitude. Taxa generally related to coastal regions are restricted to basins near to the Caribbean Sea

Cladocera of the Lençóis Maranhenses (NE - Brazil): faunal composition and a reappraisal of Sars' Method

We studied the Cladocera of a group of ephemeral interdunal pools in the Lençóis Maranhenses, Maranhão State (NE - Brazil) and recorded 34 species. The fauna was overwhelmingly neotropical, with no evidence of invasive species. Species composition differed in Lagoa da Colher, an acid system. We provide notes on behaviour, morphology and taxonomy of some lesser-known anomopods, with emphasis on the Chydoridae. We figure male Oxyurella longicaudis, Chydorus eurynotus, Disparalona leptorhyncha, Alonella dadayi and A. clathratula. We provide notes on the "Sars' Method", hatching of freshwater crustaceans from dry mud, a simple technique that complements the information of hit-and-run surveys. About half of the total species number (44%) was revived through this method; 18% of species were additional to field-collected samples. The Sars' method also yielded abundant specimens of rare species, useful for identification and studies on behaviour