Search

Aim Tropical America, including the Tropical Eastern Pacific and the Caribbean Sea, presents a high level of marine biodiversity, but its fish fauna has been poorly documented. In early studies marine species distributions were interpreted based on tectonic activity during the late Cenozoic, while more recent studies have highlighted a link with the present-day environment. Here, we described the assemblage richness and composition of fishes in Tropical America and related these properties to both the past evolution of marine environmental conditions and current environmental gradients. Location Tropical America. Taxon Demersal and benthic fishes. Methods We mapped the distribution of 2,216 demersal and benthic fish species of Tropical America using existing occurrence data. We computed three assemblage indicators: species richness, composition and nestedness, which we explained by environmental gradients. We linked compositional distance to environmental differences using distance-based redundancy analysis, species richness and nestedness using a generalized linear model. We ran simulations of a mechanistic model in which three processes determine the spatial dynamics of biodiversity: speciation, dispersal and extinction. This model yielded estimates for species assemblage properties following palaeogeographic changes in the region that shaped the current coastal habitat configuration. Results Fish species richness in Tropical America peaks around the Florida Peninsula, Bahamas and Greater Antilles. Fish composition varies along a depth gradient, between the Tropical Eastern Pacific and the Caribbean Sea, and forms distinct domains within the Caribbean region. The nestedness component of beta-diversity is lower in shallower assemblages, especially those along the outer section of the Greater Caribbean. Species richness and nestedness are partly explained by current environmental conditions, but model simulations illustrate how this may be further explained by the tectonic history of the region. Main conclusions Species richness peaks in the Greater Caribbean, coinciding with generally favourable current environmental conditions for demersal and benthic fishes. The high species richness and the low nestedness of fish assemblages in the Cuba region are compatible with the results of palaeo-environmental changes that have occurred in that area. Effects of the plate tectonic history might still be present in the organization of fish fauna in this region. ISSN:0305-0270 ISSN:1365-2699

Acanthonus armatus Günther, 1878 is reported for the first time in the southwestern Caribbean region, off Colombia. Remote Operate Vehicle videos and towed camera still photographs captured 13 images of A. armatus between 2215 and 2564 m. These are the first records of the species in the Caribbean continental coast of Colombia, representing a range extension to the southwestern Caribbean region, since previous records are from the northeastern Caribbean. Some photos of the specimens and the current distribution of the species in the Caribbean region are provided and reviewed.

International audience; Through the development of environmental DNA (eDNA) metabarcoding, in situ monitoring of organisms is becoming easier and promises a revolution in our approaches to detect changes in biodiversity over space and time. A cornerstone of eDNA approach is the development of primer pairs that allow amplifying the DNA of specific taxonomic groups, which is then used to link the DNA sequence to taxonomic identification. Here, we propose a framework for comparing primer pairs regarding (a) their capacity to bind and amplify a broad coverage of species within the target clade using in silico PCR, (b) their capacity to not only discriminate between species but also genera or families, and (c) their in situ specificity and efficiency across a variety of environments. As a case study, we focus on two mitochondrial 12S primer pairs, MiFish-U and teleo, which were designed to amplify fishes. We found that the performance of in silico PCRs were high for both primer pairs, but teleo amplified more genera acrossActinopterygii, Chondrichthyes, and Petromyzontomorphi than MiFish-U. In contrast, the discriminatory power for species, genera, and families were higher for MiFish-U than teleo, likely associated with the greater length of the amplified DNA fragments. The evaluation of their in situ efficiency showed a higher recovered species richness ,of teleo compared to MiFish-U in tropical and temperate freshwater environments, but that generally both teleo and MiFish-U primers pairs perform well to monitor fish species. Since more species were detected when used together, those primer pairs are best used in combination to increase the ability of species detection.

Se realizo un inventario de la fauna ictica de la region Guajira, a partir de muestras colectadas en un crucero efectuado entre Palomino y Punta Espada en las isobatas de 10 y 50 m, del 30 de marzo al 8 de abril de 2005, a bordo del buque de investigaciones B/I ANCON (INVEMAR). Se colectaron 3662 ejemplares, distribuidos en 51 familias, 113 especies y cuatro morfotipos identificados a nivel de genero. Diecisiete de estas especies fueron nuevos registros para el area de estudio. Se evaluo si existian diferencias significativas en la composicion y abundancia de la fauna ictica entre las ecorregiones Guajira y Palomino y entre las diferentes profundidades. Los resultados evidenciaron que La Guajira posee una gran diversidad de peces que forman ensamblajes a nivel de la plataforma, principalmente siguiendo una estratificacion vertical y en menor grado una configuracion ecorregional. Dicho patron se encuentra posiblemente relacionado con el tipo de fondo y las caracteristicas ambientales especificas que lo acompanan

Checklist of fish larvae recorded in the Colombian Caribbean. A taxonomic checklist of larval stages of fish species recorded in the Colombian Caribbean is presented, as a product of an extensive literature review of studies on the topic. Eighty five family records included in 21 orders, with a total of 129 species were found. In terms of composition, the order Perciformes has shown the highest number of families (41), genera (66) and species (46). The families Carangidae and Exocoetidae were the richest. In terms of distribution, it was evident a bigger sampling effort in La Guajira, Magdalena and San Andres y Providencia provinces.

Se hace un recuento de la riqueza íctica de los mares colombianos, enfatizando en los grupos amenazados de extinción en nuestras aguas y los factores de amenaza que se ciernen sobre ellos. Se detectan claras diferencias entre los peces cartilaginosos y los óseos en cuanto a sus posibilidades de supervivencia, pues mientras de los primeros 33% (41) de las especies conocidas de Colombia se hallan amenazadas o cerca de estarlo, solo 4% (89) de los óseos tienen esa condición. Así mismo, los niveles de conservación existentes en el Pacífico colombiano son aun claramente superiores a los del Caribe, lo cual indudablemente se asocia con la mucha mayor población humana que ocupa la costa norte colombiana. Se detallan los casos de los órdenes Carcharhiniformes (tiburones y toyos), Rhinopristiformes (peces sierra, rayas guitarras, rayas brujas), Elopiformes (sábalo) y Labriformes (peces loro) y de la familia Serranidae (meros) por considerarse ejemplos críticos que muestran la urgencia de una acción rápida, enmarcada tanto en los factores intrínsecos de amenaza de las especies, como en las necesidades de la sociedad para salvaguardar el medio circundante. A review of the Colombian marine fish richness is made, emphasizing on those groups susceptible of extinction and on the factors threatening them. There are clear differences between the conservation level of Colombian bony and cartilaginous fishes; 41 species of elasmobranch fishes (33% of total) are threatened or close to be, but only 4% (89 species) of the total figure of bony fishes have such status. Colombian Caribbean fishes are also more severely threatened than Pacific ones, which should be related to the higher density of human population in the northern Colombian coast. The cases of the orders Carcharhiniformes (requiem sharks), Rhinopristiformes (guitarfishes, saw fishes, witch rays), Elopiformes (tarpon) and Labriformes (parrotfishes) and the family Serranidae (groupers) are discussed in detail because they are considered critical examples showing the need of urgent action, based both on intrinsic threat factors as well as on societal needs to manage the environment.

The lionfish Pterois volitans is an invasive species throughout the Western Atlantic that disturbs functioning of local ecosystems such as coral reefs via fast and intense consumption of small fish and invertebrates. In 2009, lionfish populated the bays of Tayrona National Natural Park (TNNP), a biodiversity hotspot in the Colombian Caribbean that is strongly influenced by changing environmental conditions due to a rainy and dry season. So far, the spatial and temporal distribution of P. volitans in the bays of TNNP is unknown. Therefore, this study assessed the abundance and body lengths of P. volitans during monthly surveys throughout the year 2012 in four bays (thereof two bays where lionfish removals were undertaken) of TNNP at 10 m water depth in coral reefs using transect tools. Findings revealed lionfish abundances of 2.9 ± 0.9 individuals ha(-1) with lengths of 20-25 cm for TNNP, hinting to an established, mostly adult local population. Actual TNNP lionfish abundances are thereby very similar to those at Indo-Pacific reef locations where the invasive lionfish formerly originated from. Significant spatial differences for lionfish abundances and body lengths between different bays in TNNP suggest habitat preferences of P. volitans depending on age. Lionfish abundances were highly variable over time, but without significant differences between seasons. Removals could not reduce lionfish abundances significantly during the period of study. This study therefore recommends improved management actions in order to control the already established invasive lionfish population in TNNP.