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Use of food and spatial resources by two frogs of the genus Dendropsophus (anura: Hylidae) from La Selva, Costa Rica
(Universidade de Sao Paulo, 2012-06)
Differences in the use of resources by similar species have been related to a reduction in the interspecific competition that allows coexistence. Also, other factors, such as high availability of resources in the environment, ...
Camelobaetidius guaycara, a new species of Baetidae (Ephemeroptera) from Costa Rica, Central America
(Magnolia Press, 2018-06-14)
The nymphs of a new species of Camelobaetidius (Ephemeroptera: Baetidae) possibly related to the South American species of this genus were found on the Atlantic and Pacific slopes of Costa Rica. Among other characteristics ...
Characteristics of the venoms and digestive secretions of Aphonopelma seemanni and Sphaerobothria hoffmanni (Araneae: Theraphosidae) of Costa Rica
(Universidad de Costa Rica, 1987)
A comparison of some components of the venoms of two Costa Rican tarantulas, Aphonopelma seemanni (Cambridge) and Sphaerobothria hoffmanni (Karsch) by polyacrylamide gel electrophoresis shows patterns similar to those of ...
Aspectos relevantes en la biología de Cetengraulis mysticetus (GÜNTHER) (Pisces: Engraulidae) en el Golfo de Nicoya, Costa Rica.
(Universidad Nacional [Costa Rica ], 1998-01-01)
Cetengraulis mistycetus es una anchoveta americana, que se encuentra localizada en la costa americana de México hasta Perú. Su valor comercial es relevante en la parte interna del Golfo de Nicoya, ya que la flota artesanal ...
Simulación de una cohorte de Anchoa Panamesis (Steindachner, 1975) en el Golfo de Nicoya, Costa Rica
(Universidad Nacional [Costa Rica], 1987-01-01)
Se aplica el modelo de simulación de stock de Jansen a una cohorte hipotético de 100.000 peces de Anchoa panamensis, utilizando una tasa de mortalidad natural de 0.274 mensual, obtenida para esta población en 1981 y dos ...
Participación de las lombrices de tierra en el ciclo del nitrógeno, con énfasis en los sistemas agroforestales de Costa Rica
(Universidad Nacional [Costa Rica], 1989-01-01)
Las lombrices de tierra contribuyen a la generación de biomasa en la fauna, en conjunto con el nitrógeno (N) nutriente imprescindible para las plantas y animales este proceso contribuye a la fertilidad del suelo. De ahí ...
Desarrollo del comportamiento agresivo en el Guapote Tigre (Cichlasoma Managunse, cichlidae) en relación con el crecimiento y la coloración de juveniles en cultivo intensivo.
(Universidad Nacional (Costa Rica), 1998-01-01)
Se tipifican las coloraciones juveniles y adultas del guapote tigre y se realiza un inventario de los despliegues agresivos de juveniles. En 5 cohortes peces en condiciones de cultivo intensivo se analiza la evolución del ...
Composition, growth and condition index for a population of Poecilia reticulata (Pisces: Poeciliidae), in a pond in Heredia, Costa Rica
(Universidad Nacional, Costa Rica, 2003)
A pond population of Poecilia reticulata was studied in Santo Domingo, Heredia, Costa Rica, between September and November of 1998. The sex ratio was 1:0.49 (males:females). The mean total length was 34.43 ± 7.26 mm for ...
Contrasting patterns of taxonomic, phylogenetic and functional variation along a Costa Rican altitudinal gradient in the plant family Melastomataceae
(Cambridge University Press, 2018)
The functional composition of plant communities in montane regions has been studied for decades, and most
recent analyses find that environmentally favourable landscapes at lower altitudes tend to be dominated by species ...
Crecimiento y maduración sexual de Astyanax fasciatus (Pisces: Characidae) en el embalse Arenal, Guanacaste, Costa Rica
(Universidad de Costa Rica, 1997)
Growth and sexual maturation of Astyanax fasciatus were studied in shallow areas of the Arenal reservoir in Costa Rica. Von Bertalanffy's equation was 11 = 167.3 (l - e(-0.093 ,-0.132). The mean growth for the first six ...