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The reproduction and diet were studied in Mabuya dorsivittata a viviparous lizard from Alto Alegre (Córdoba). The smallest female with yolking ovarian follicles measured (svl) 41 mm, and the smallest male with spermatozoa in the testes measures (svl) 31mm. The litter size was from five to ten embryos. A positive and significant correlation existed between the weight of the eggs or embryos and the reproductive state (B = 0,524, R = 0,254, P 0,001). In males there was a positive and significant correlation between the testicular volume and the reproductive state (R2 = 0,851, b= 0,929, P= 0,002). The mass of fat bodies in females and males was related with the reproductive period, especially in the females, diminishing in the final phases of embryo development, indicating a high energetic cost during the last months of embryonic growth. Regarding the diet, females fed mainly on soil Araneae as fundamental prey, Scarabeidae, Araneae (others) and Acridiidae as secondary prey, whereas males fed on Isopoda, Acridiidae and Araneae as fundamental prey and on Tettigonidae as secondary prey. There were significant differences in trophic selection among sexes.

We present a waterbird inventory corresponding to 66 wetlands in the southeast of the Province of Córdoba, Argentina. Sixty six waterbird species belonging to 16 families and eight orders were recorded. We report observations of 11 neartic migratory, seven partial migratory and one altitudinal migratory species. Records of Callonetta leucophrys, Pluvialis dominica and Limosa haemastica considered rare species for the region, were recorded in this study. Data of the relative abundance revealed 10 very abundant species, 16 abundant, 25 scarce and 12 rare, while the relative importance identified nine frequent species, 19 non-frequent and 35 occasional. This work enhances baseline knowledge of waterbirds to assist future studies in this highly threatened area with high biodiversity.

A new species of the genus Teius Merrem 1820 from Cordoba, Argentina is described, the unisexual Teius suquiensis n. sp. The morphology, colour pattern and distribution of the new species and the bisexual T. teyou (Daudin 1802) and T. oculatus (d'Orbigny & Bibron 1837) are discussed.

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ABSTRACT. Characterization of Culicidae larvae (Diptera) consumption in two species of native fish in the central zone of Argentina. Mosquitoes represent a threat to human health and animals because they act as vectors of several diseases. Native fish species are potential candidates to be considered for biological control populations of mosquitoes. Tests of half-hour and 24-hour consumption of Culex pipiens (Linnaeus, 1758) larvae by Cnesterodon decemmaculatus (Jenyns, 1842) and Jenynsia multidentata (Jenyns, 1842) were carried out, measuring the standard length, mouth width and weight in individuals of the two species of fishes. In both tests J. multidentata consumed more C. pipiens than C. decemmaculatus, being C. decemmaculatus female consumption higher than male consumption (and equal than both sexes of J. multidentata in the 24-hour test). These results remained unchanged when making comparisons of absolute or relative consumption in the half-hour test, but when consumptions relative to weight were compared no difference between species was found in the 24-hour test. Regression analysis between morphometric variables and weight vs. consumption rates showed low explanatory value for the half-hour test, while in the 24-hour test these variables had higher explanatory value, especially for the mouth width. Finally, a half-hour test was performed over C. decemmaculatus females using C. pipiens and Aedes aegypti (Linnaeus, 1742) larvae and it showed a strong preference for the latter ones. This work allowed us to observe that there are large differences in consumption rates of C. pipiens larvae between the fish species under study in short periods. Differences are attenuated when consumption times are longer and may even disappear when weight is taken into account. KEYWORDS.Cnesterodon decemmaculatus, Jenynsia multidentata, biocontrol, mosquito larvae. RESUMEN.Los mosquitos representan una amenaza para la salud del hombre y de los animales debido a que actúan como vectores de distintas enfermedades. Especies de peces nativos son potenciales candidatos a tenerse en cuenta para control biológico de poblaciones de culícidos. Experiencias de consumo de media hora y de 24 horas por Cnesterodon decemmaculatus (Jenyns, 1842) y Jenynsia multidentata (Jenyns, 1842) se llevaron a cabo con larvas de Culex pipiens (Linnaeus, 1758), midiéndose longitud estándar, ancho de boca y peso en individuos de las dos especies. En ambas pruebas, J. multidentata consumió más C. pipiens que C. decemmaculatus, consumiendo las hembras de esta última especie más que los machos (e igual a ambos sexos de J. multidentata en la prueba de 24 horas de duración). Estos resultados no variaron cuando se compararon tantos consumos absolutos o relativos para las pruebas de media hora, sin embargo cuando se compararon los consumos relativos al peso no se encontraron diferencias entre las especies para las pruebas de 24 horas. Análisis de regresión entre las tasas de consumo versus las variables morfométricas y el peso mostraron poco valor explicati...

Size frequencies in a population of the lizard Liolaemus wiegmannii were determined throughout the year, to evaluate the effects of recruitment and mortality on the population structure, and to estimate the daily growth rate and its variation. The cycle started in spring when most of the lizards had reached reproductive size, in December eggs were laid and the new lizards were born in January. This cohort grew rapidly and reached adult size in late March, while the postreproductive cohort died in late fall. The differences between growth rates during the year are due to the seasons and the size of the lizards during the period.

The reproductive cycle of the parthenogenetic lizard Teius suquiensis was studied. Females were reproductive after their second winter. The first eggs were laid in early November and oviductal eggs were present up to early January. Mean clutch size was 4.2 (range 2-8). Fat bodies were smallest during the reproductive season.