The aquatic biota of the now extinct lacustrine complex of the Mexico basin

The commonest organisms of the original Mexico lake complex are listed, including those that exist today in the Lago Viejo. In addition, a brief hydraulic history of this endorheic basin is given

Isopods of the Genus Excorallana Stebbing, 1904 (Crustacea, Isopoda, Corallanidae) from the East Coast of Mexico with a Supplemental Description of E. subtilis

Eight species of Excorallana, E. acuticauda, E. delaneyi, E. oculata, E. sexticornis, E. subtilis, E. tricornis tricornis, E. warmingii, and Excorallana sp. are recorded for the eastern coast of Mexico. The range of E. delaneyi is extended south in the Gulf of Mexico. Excorallana oculata and E. subtiIis are reported for the first time in the Gulf. Based on specimens from the east coast of Mexico, a supplemental description of E. subtilis is presented and its taxonomy to other closely related species discussed. A key is provided to the adult males of the species of Excorallana now known to occur in the southwestern Gulf of Mexico and the Caribbean coast of Mexico

Isopods of the Genus Excorallana Stebbing, 1904 (Crustacea, Isopoda, Corallanidae) from the East Coast of Mexico with a Supplemental Description of E. subtilis

Eight species of Excorallana, E. acuticauda, E. delaneyi, E. oculata, E. sexticornis, E. subtilis, E. tricornis tricornis, E. warmingii, and Excorallana sp. are recorded for the eastern coast of Mexico. The range of E. delaneyi is extended south in the Gulf of Mexico. Excorallana oculata and E. subtiIis are reported for the first time in the Gulf. Based on specimens from the east coast of Mexico, a supplemental description of E. subtilis is presented and its taxonomy to other closely related species discussed. A key is provided to the adult males of the species of Excorallana now known to occur in the southwestern Gulf of Mexico and the Caribbean coast of Mexico

How Does Financial Globalization Affect Government Size?

More open economies have larger governments because the public sector functions as a compensatory mechanism against risks associated with trade and financial globalization.York's Knowledge Mobilization Unit provides services and funding for faculty, graduate students, and community organizations seeking to maximize the impact of academic research and expertise on public policy, social programming, and professional practice. It is supported by SSHRC and CIHR grants, and by the Office of the Vice-President Research & Innovation. [email protected] www.researchimpact.c

ROV's Video Recordings as a Tool to Estimate Variation in Megabenthic Epifauna Diversity and Community Composition in the Guaymas Basin

Patterns in benthic megafauna diversity in littoral and intertidal zones in the Gulf of California have been associated with both habitat heterogeneity and substrate type. Current knowledge of invertebrate communities in hard bottom habitats at depths > 200 m in the Gulf is poor due to the methodological limitations inherent in sampling deep habitats. Using video imagery of benthic habitats coupled with environmental data from the Remotely Operated Vehicle Doc Ricketts, we documented variation in the diversity and community composition of the benthos from 849 to 990 m depth in the NW limit of the Guaymas Basin, in relation to dissolved oxygen and substrate characteristics. This depth range overlaps an oxygen minimum zone where oxygen drops to levels < 0.5 ml L-1 and strong gradients in a narrow depth range occur. Dissolved oxygen varied along our benthic survey from 0.200 to 0.135 ml L-1. We observed high taxonomic richness across an area of rocky outcrops through the lower transition zone. This megafaunal pattern differs from reports from other oxygen minimum zones characterized by a great abundance of a few species. Taxonomic richness diminished at depths with reduced dissolved oxygen in the lower boundary of the oxygen minimum zone with increasing soft sediment cover. We found that rocky outcrops and structure-forming organisms such as corals, sponges, and oyster aggregations supported a higher diversity (H' = 0.8) than soft sediment (H' = 0.7) as have been observed in other habitats such as seamounts. Environmental variables that explained most of the megafaunal variation were substrate type (18.4%), depth (1.14%) and temperature (0.9%). Salinity (0.45%) and dissolved oxygen (0.3%) were less important factors to explain the megafaunal composition variance. Substrate type played a key role in the diversity and composition of benthic megafauna. These results broaden our understanding concerning the potential roles of substrate characteristics in the community composition of the deep-sea benthic megafaunal assemblages in the Gulf of California and oxygen minimum zones in general

Freshwater biological research in Mexico: A brief historical review

Apart from a couple of early papers in the 1600s, the development of freshwater biology as a science in Mexico began in the last century. Taxonomic studies were made especially on algae, aquatic insects, crustaceans, annelid worms and aquatic plants. The great impetus acquired by limnology in Europe and America in the first half of the 20th Century stimulated foreign researchers to come and work in Mexico. During this period the Instituto de Biologia, belonging to the Universidad Nacional Autonoma de Mexico, was created in 1930. The Institute had a section of Hydrobiology that contributed to the limnological characterization of Mexican lakes and ponds. In 1962, the Instituto Nacional de Investigaciones Biologico-Pesqueras was created to bring together the work of several institutes working on the native ichthyofauna, the restocking of reservoirs, and aquaculture

The aquatic biota of the now excinct lacustrine complex of the Mexico basin

The Valley of Mexico is an endorheic basin (i.e. there is no natural outlet)lying on the highest portion of the Mexican Plateau (2240-2390 metresabove sea level) between 19&deg;01'18" to 20&deg;09'12" N and 98&deg;31'58" to99&deg;30'52" W. It is oval in shape, with a north-south axis 125 km in lengthand a shorter east-west axis of 90 km, averaging 7,868 km&sup2; in area(Alvarez &amp; Navarro 1957; Mora 1991)

Freshwater biological research in Mexico; A brief historical review

The first notice of freshwater biological observations carried out inMexico is contained in the ancient nahuatl codexes. In these, freshwaterfishes, waterfowl and aquatic insects are depicted, showing capturemethods, techniques and limnological observations such as changes inthe water level of Lake Texcoco in 1519. All this information began withthe arrival of the aztecs to the Valley of Mexico in 1245. An "azteclimnology" is defined by Deevey (1957) as all of the observationsincluded in the codexes

Diversidad regional de Amphipoda en el mar Caribe

The order Amphipoda is one of the most diverse within Peracarids, and comprises 6 950 described marine species. Amphipod research in the Caribbean Sea began in the late 1 800s, but has increased significantly since 1 980. In this study, we analized the amphipod biodiversity (Caprellidea, Gammaridea, Hyperiidea, and Ingolfiellidea) of the Caribbean Sea. For this, we compiled available data on species diversity of marine amphipods (data bases: WoRMS and OBIS and published species lists) into a comprehensive taxonomic list by country for the ecoregions of the Caribbean. Additionally, we analized the relative contribution of each country to regional diversity and the rate of discovery of new species. The Caribbean amphipod fauna is composed of 535 species within 236 genera and 73 families for the higher taxon. The Western Caribbean ecoregion holds the largest diversity (282 species), while the Eastern Caribbean recorded the lowest one (73). Mexico and Venezuela recorded the largest number of species with 266 and 206, respectively. Twelve countries had less than 50 species. The richest suborder is the Gammaridea with 381 species followed by the suborder Hyperiidea with 116. From the total of 535 amphipod species reported for the Caribbean region, 218 have the Caribbean as the holotype locality, and 132 are endemic (about 25% of the total). Areas of higher diversity seem to be concentrated along the Mexican Caribbean, Cuba and the Northern coast of South America (VenezuelaColombia); however, such pattern is most likely reflecting local collection efforts and taxonomic expertise rather than actual distribution. Knowledge of amphipod species is mostly limited to shallow, near-shore waters, with little information available on the deep sea fauna. Regional research priorities for this group should be focused on completing shallow water coastal inventories of species in Central America and the Greater and Lesser Antilles. In addition, sampling the deep sea ecosystems should follow along with other particular habitats such as anchialine cave systems. It is also neccessary to increase ecological research efforts, mainly in some speciose suborders, including the Caprellidea and Hyperiidea, known to exhibit high diversity in other tropical localities