Juan Armando Sánchez

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Despite their abundance and ecological importance in a wide variety of shallow and deep water marine communities, octocorals (soft corals, sea fans, and sea pens) are a group whose taxonomy and phylogenetic relationships remain poorly known and little studied. The group is currently divided into three orders (O: Alcyonacea, Pennatulacea, and Helioporacea);(More)
Understanding patterns of connectivity among populations of marine organisms is essential for the development of realistic, spatially explicit models of population dynamics. Two approaches, empirical genetic patterns and oceanographic dispersal modelling, have been used to estimate levels of evolutionary connectivity among marine populations but rarely have(More)
Coral-algal symbiosis has been a subject of great attention during the last two decades in response to global coral reef decline. However, the occurrence and dispersion of free-living dinoflagellates belonging to the genus Symbiodinium are less documented. Here ecological and molecular evidence is presented demonstrating the existence of demersal(More)
Despite the relative simplicity of their modular growth, marine invertebrates such as arborescent gorgonian octocorals (Octocorallia: Cnidaria) generate complex colonial forms. Colony form in these taxa is a consequence of modular (polyp) replication, and if there is a tight integration among modular and supramodular traits (e.g. polyp aperture, inter-polyp(More)
As part of an ongoing program to explore the chemical constituents of Caribbean marine invertebrates, a family of 13 new diterpene glycosides, pseudopterosins P-Z (1-11) and seco-pseudopterosins H (12) and I (13), have been isolated from the organic extracts of two collections of the sea whip Pseudopterogorgia elisabethae procured near the Colombian(More)
BACKGROUND The rising temperature of the world's oceans has become a major threat to coral reefs globally as the severity and frequency of mass coral bleaching and mortality events increase. In 2005, high ocean temperatures in the tropical Atlantic and Caribbean resulted in the most severe bleaching event ever recorded in the basin. METHODOLOGY/PRINCIPAL(More)
The anthozoan sub-class Octocorallia, comprising approximately 3000 species of soft corals, gorgonians, and sea pens, remains one of the most poorly understood groups of the phylum Cnidaria. Efforts to classify the soft corals and gorgonians at the suprafamilial level have long thwarted taxonomists, and the subordinal groups in current use are widely(More)
Growth rates of branches of colonies of the gorgonian Pseudopterogorgia elisabethae were monitored for 2 years on a reef at San Salvador Island, Bahamas. Images of 261 colonies were made at 6-month intervals and colony and branch growth analyzed. Branch growth rates differed between colonies and between the time intervals in which the measurements were(More)
Coral reefs are declining worldwide due to increased incidence of climate-induced coral bleaching, which will have widespread biodiversity and economic impacts. A simple method to measure the sub-bleaching level of heat-light stress experienced by corals would greatly inform reef management practices by making it possible to assess the distribution of(More)
Dengue fever is perhaps the most important viral re-emergent disease especially in tropical and sub-tropical countries, affecting about 50 million people around the world yearly. In Colombia, dengue virus was first detected in 1971 and still remains as a major public health issue. Although four viral serotypes have been recurrently identified, dengue virus(More)