Se describe la araneofauna urbana en el área de Ciudad Victoria, Tamaulipas, México y su distribución sobre la mancha urbana. Se realizó un muestreo por conglomerados en tres etapas y se identificaron 59 especies correspondientes a 29 familias. Se encontraron dos nuevos registros para el estado y se presentan los valores de riqueza específica, diversidad y equitatividad, así como los valores desinantropía asociados a las especies. Además se analizó la similitudentre cinco zonas de la ciudad.

Predatory capacity and prey selectivity of nymphs of the dragonfly Pantala hymenaea (Odonata: Libellulidae) were evaluated on larvae of the mosquito Culex quinquefasciatus (Diptera: Culicidae) and larvae of the midge Chironomus plumosus (Diptera: Chironomidae) as prey. With functional response methodology, 7 larval densities were exposed to predator individuals in a glass jar under laboratory conditions. The study was performed in 2 experiments. The 1st was a test system with each prey species alone. The 2nd tested a mixture of both prey species in a 1:1 ratio. Prey selectivity and prey capacity were significantly greater on midge larvae than on mosquito larvae.

No abstract

Backswimmers have been recognized as the most promising predators of mosquito larvae. The aim of this investigation was to study mass rearing and egg release of Buenoa scimitra for the biological control of Culex quinquefasciatus Say. Among the most important results were that production of backswimmer eggs occurred for 263 days, and also that eggs were released in artificial containers with production of new individuals until the adult stage was obtained. In addition, a statistically significant reduction in mosquito larval density was observed on some sampling dates.

Major adsorbent materials used in heavy metal ion removal from polluted aqueous streams are expensive and difficult to regenerate. In this study, the possibility of using pectin, as an alternative biosorbent material to remediate heavy metal pollution was investigated. The effects of different parameters such as pH, concentration and temperature of metal solution, and contact time on the biosorption process were studied. The maximum removal efficiency was obtained at pH 2.0 for lead and zinc and pH 4.0 for cadmium. For most of the metals tested, a contact time of 15 minutes was sufficient for achieving the maximum removal. There was no significant influence on the removal capacity of pectin by the concentration and temperature of the metal solution. Under these experimental conditions the biosorption was favorable (65% lead, 42% zinc and 55% cadmium). The ability to use pectin for the removal or recovery of metals from aqueous solutions is evident.