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The present study provides information on the composition and seasonal abundance of the families Chrysopidae, Coniopterygidae and Hemerobiidae associated with Mexican lime trees [Citrus aurantifolia (Christm.) Swingle] in Tecomán, Colima. The study was conducted in a Mexican lime orchard, untreated chemically. Field surveys were carried out during 13 months, from May 2013 to June 2014. Sampling was carried out monthly using 5 collecting techniques: Malaise trap, sweeping net, aerial net, yellow pan traps, and canopy fogging. A total of 508 specimens were collected, placed in 3 families and 21 species, 6 of those are new citrus records worldwide, 7 are new distribution records for Colima state, and 7 are new citrus records in Mexico. The most abundant and frequent species were Ceraeochrysa cubana (Hagen, 1861), Ceraeochrysa cincta (Scheider, 1851) and Chrysoperla externa (Hagen, 1861). Diversity of order 1, including the species of the 3 families and their relative abundance, was 7.1 effective species; and during the first period of vegetative sprouting of Mexican lime trees, the 3 families share maximum values of diversity. The results have implications for the conservation and use of the diversity of Neuroptera associated with citrus trees in the state.

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Evidence is accumulating on the importance of plant cover and plant species composition on the control of ecosystem processes. In this study we examined a gradient considering the proportional contribution of the key species Bouteloua gracilis H.B.K. Lag. to assess its influence on the average and dynamic changes in soil water content in the shortgrass steppe from Central Mexico. We chose 4 sites with the following proportions of the key species: , 25%, 25%-50%, 50%-75%, and. 75%, ascribing each proportion to the range condition categories poor, fair, good, and excellent, respectively. Soil water measurements were carried out during 14 months at the 4 sites. Our results showed that range condition had a significant effect on soil water content (P , 0.01). The excellent condition was overall 14.5% and 12.5% lower soil moisture content compared to the poor and good range conditions (P , 0.01), respectively. Our results indicated a negative correlation between the gradient of soil water content with the range condition classes. Soil water content dynamics also differed among range condition classes, with the excellent condition showing both faster water recharge and extraction patterns than the other 3 range condition categories. Differences in soil water content among the range condition classes appeared to be related to morphological and physiological traits associated with the dominant species cover observed at each site. These results offer insights into the importance of vegetation characteristics as potential indicators of thresholds in grazing ecosystem processes such as soil water dynamics. Resumen Existen bastantes evidencias sobre la importancia que tiene la cubierta vegetal y la composició n de las especies en el control de los procesos de los ecosistemas. En el presente estudio, examinamos un gradiente definido por la contribució n proporcional de la especie clave Bouteloua gracilis en la comunidad, para evaluar su influencia en el contenido promedio y la diná mica del agua en suelo de los pastizales semiá ridos del Centro de México. Seleccionamos 4 sitios con la siguiente proporció n de la especie clave en la comunidad , 25%, 25%-50%, 50%-75%, y. 75%, asignando cada proporció n a las siguientes categorías de condició n pobre, regular, buena y excelente, respectivamente. Se realizaron mediciones de humedad en suelo en los 4 sitios durante 14 meses. Nuestros resultados muestran que la condició n del pastizal tuvo un efecto significativo sobre el contenido de agua en suelo (P , 0.01). La condició n excelente, por ejemplo, mostró 14.5% y 12.5% menos contenido de agua en suelo comparado a la condició n pobre y buena respectivamente. Nuestros resultados exhiben una correlació n negativa entre el gradiente del contenido de agua y las clases de condició n del pastizal. La diná mica del contenido de agua en suelo, también difirió entre clases de condició n, con la condició n excelente exhibiendo tanto las tasas de recarga como las tasas de extracció n mas rá pidas. Las diferencias observadas en el contenido de a...