Distribución de cangrejos ermitaños (Anomura: Paguroidea) en el mar Caribe colombiano / Hermit crabs (Anomura: Paguroidea) distribution patterns in the Colombian Caribbean Sea

Hermit crabs (Anomura: Paguroidea) distribution patterns in the Colombian Caribbean Sea. Hermit crabs represent the marine life in the Colombian Caribbean, and are important for the dynamic equilibrium maintenance in ecosystems, the ecological interactions and their impact on food web stability. Generally, in order to come up with some conservation strategies, strong bio-geographical information is needed for policies definition. With this aim, this study analyzed the distribution patterns of hermit crabs in the Colombian Caribbean Sea, through classification and spatial ordination multivariate analyses, using historical records from years 1916 to 2006. Besides, the world distribution of Colombian species and their geographic affinity in the Caribbean and Western Atlantic were identified. The results show deep differences between coastal and continental slope faunas, and latitudinal differences in the assemblages, with the identification of three groups: Northeast, Center and Southwest. The differences in faunal composition that support these three groups were determined. Based on maps of the Colombian marine ecosystems, it was found that the main factors affecting the distribution of hermit crabs were the Caribaná slope (depth), water-mass temperature, Guajira sea-grass beds, and particular conditions of “Coralline Archipelagos” and “Darién” eco-regions. Colombian hermit crab fauna is more related to the North Atlantic and the Antilles, than to the South Atlantic and the Gulf of Mexico. Additionally, geographical sub-provinces in which Colombia is included, these were found as transition zones among Northern and Austral subprovinces of the Greater Caribbean.

Los cangrejos ermitaños son un grupo representativo de la fauna marina del Caribe colombiano, además, son importantes en el mantenimiento del equilibrio dinámico, en los ecosistemas por sus interacciones ecológicas y también por el impacto en la estabilidad de las redes tróficas. Sus patrones de distribución se identificaron mediante análisis multivariados de clasificación y ordenación espacial, se usaron registros históricos desde 1916 hasta el 2006. Los resultados indican diferencias por profundidad entre la fauna costera y la del talud continental y diferencias en la distribución latitudinal, en donde se encontraron tres grupos: Noreste, Centro y Suroeste, sustentados por diferencias en la composición faunística. Con base en los mapas de ecosistemas marinos de Colombia, se determinó que los principales factores que afectan su distribución son la influencia del talud Caribaná (profundidad), la temperatura de las masas de agua, las praderas de pastos marinos de la Guajira y las condiciones particulares de las ecorregiones Archipiélagos coralinos y Darién. Se identificó la distribución mundial de las especies colombianas y su afinidad geográfica, y se encontró mayor afinidad con el Atlántico norte y las Antillas que con el Atlántico sur y el Golfo de México, asimismo, las subprovincias geográficas que incluyen a Colombia son zonas de transición dentro de la subprovincias septentrionales y australes del Gran Caribe.

The Brachyura and Anomura fauna (Decapoda; Crustacea) in the Arvoredo Marine Biological Reserve on the southern brazilian coast

Eight species of Brachyura and two species of Anomura were registered for the first time on the Santa Catarina coast, in the waters around the Arvoredo Marine Biological Reserve. The animals were collected by scuba divers, between 3 and 22 meters depth, from September 2001 to February 2003. A total of 31 decapod species were collected, and most of the new occurrences had already been registered in the adjacent northern waters.

Oito espécies de Brachyura e duas espécies de Anomura foram registradas pela primeira vez na costa de Santa Catarina, em águas no entorno da Reserva Biológica Marinha do Arvoredo. Os animais foram coletados por meio de mergulho autônomo, entre 3 e 22 metros de profundidade, de setembro 2001 a fevereiro de 2003. Um total de 31 espécies de Decapoda foram coletadas e a maioria das novas ocorrências já haviam sido registradas em águas adjacentes ao norte da Reserva.

Biodiversidad marina de Costa Rica: Crustacea: Infraorden Anomura / Marine biodiversity of Costa Rica: Crustacea: Infraorder Anomura

The anomuran crabs are among the best known crustacean groups from the Pacific coast. However, this group is poorly known from the Caribbean coast of Costa Rica. In this compilation based on the literature and the collection at the Zoology Museum, Biology School, University of Costa Rica, we report the presence of 114 species of the Infraorder Anomura for Costa Rica, 20 species from the Caribbean, 96 species from the Pacific (two are present on both coasts). Twenty-nine species are new reports for Costa Rica, 15 from the Caribbean coast (74% of the total of species from that coast) and 14 from the Pacific (15% of the total from the Pacific). The range often species is extended to Costa Rica, siete from the Caribbean and three from the Pacific. Six species are reported for the first time from Cocos Island, where there are also four endemic species.

El grupo de los cangrejos anomuros es uno de los mejor conocidos de la costa Pacífica de Costa Rica, pero muy poco conocidos de la costa Caribe. En esta recopilación, basada en la literatura y en las colecciones del Museo de Zoología, Escuela de Biología, Universidad de Costa Rica, informamos de la presencia de 114 especies del Infraorden Anomura en Costa Rica, 20 especies del Caribe, 96 especies del Pacífico, y dos especies presentes en ambas costa. Veintinueve especies son informes nuevos para Costa Rica, 15 del Caribe (75% del total de especies informadas para esa costa) y 14 del Pacífica (15% del total de esa costa). La distribución de diez especies es ampliada hasta Costa Rica, siete en el Caribe y tres en el Pacífico. Seis especies son informadas por primera vez para la Isla del Coco, donde además hay cuatro especies endémicas.