The lizard that never sleeps: activity of the pampa marked gecko Homonota uruguayensis

ABSTRACT It is generally assumed that lizards are active whenever climatic conditions are favorable. Homonota uruguayensis (Vaz-Ferreira & Sierra de Soriano, 1961) is the only native gecko - and nocturnal lizard - living in the northern Pampa biome, and its ecology is poorly known. This study aimed at describing this species’ pattern of daily and annual activity and its relation with environmental temperatures. The study was conducted in the extreme south of Brazil (Rosário do Sul, State of Rio Grande do Sul), between May 2010 and January 2011 at a rocky outcrop located in the Pampa biome. The study was carried out in a total of four seasonal field trips, totalizing 1185 hours of field work. The data were collected, both during the day and the night in 6-hour shifts (duration of the sampling period). The area was randomly covered at each shift to record activity and microhabitat use by the lizards. In total 1541 specimens were recorded throughout the study. Homonota uruguayensis showed diurnal and nocturnal activity in the four seasons, with periods of daily activity varying significantly between all seasons in a cyclic and multimodal pattern, with no significant relation with environmental temperatures. There was no difference in activity related to sex and age classes. Most active lizards were found when air temperatures ranged from 14 °C to 32.9 °C (82% of active lizards) and substrate temperatures ranged from 10 °C to 32.9 °C (87% of active lizards).

Discriminating cereal and pseudocereal species using a binary system of GC/MS data: A pattern recognition approach

Various cultivars of different cereal and pseudocereal species (9 wheat, 8 barley, 1 rye, 3 oat, 2 triticale, 3 spelt, 12 corn, 3 amaranth and 9 buckwheat cultivar samples) were milled into flour, extracted using n-hexane, derivatized with trimethylsulfonium hydroxide solution, and subjected to GC? ?MS analysis. Fatty acid methyl esters and non-saponifiable compounds (phytosterols, ?-tocopherol and squalene) were identified by comparing mass spectra with the Wiley MS library. A binary system was applied in further data processing: the presence or the absence of a particular lipid component in each sample was coded with either (1) or (0). Major lipid components that were present in all analyzed flour samples were removed from further data analysis, leaving only those that represent a good pattern to differentiate the flour samples according to corresponding cereal/pseudocereal species. Pattern recognition tools (cluster analysis and principal component analysis) were applied to visualize groupings and separations among the samples. The presented approach enables the rapid differentiation of flour samples made from various cereal/pseudocereal species according to their botanical origin and gluten content, thereby, successfully avoiding exact quantitative determinations.

Ordenación de las poblaciones silvestres de pitayo y cardón en la Cuenca de Sayula, Jalisco

The ecological relationships of "pitayo" and "cardón" were studied in the Sayula, Jalisco Basin. A multivariate approach was used considering three sets of explanatory variables: geographical (FG), edaphic (E) and biotic (B). Three columnar cacti species Stenocereus queretaroensis, and S. dumortieri and Pachycereus grandis were found. According to a detrended correspondence analysis the length of the gradient was 3.59 S.D., which justifies the use of unimodal response model for the species data. Also the results of a correspondence analysis showed a sites and species pattern related to a supposed moisture gradient. Due to the presence of outliers in some variables, it was necessary to use certain passive sites in the canonical correspondence analysis. The selected variables were: a] geographical: latitude, longitude, elevation and exposure; b] edaphic: potassium content, cation exchange capacity and sand percentage. Of these components of species data variation, the first explains 28.94% and the second one 23.66%, while the interaction of both explains only 8.23%. At the biotic level, the accompanying shrubs and tree species data were related to "pitayo" and "cardón" attributes in two ways: a] as three separated populations, or b] as a complex. The better selected attributes were total cover and average height of individual in the complex, or else S. dumortieri and P. grandis, respectively, for the species strategy. However, there was a poor relation for the species (17.4%), with the variation of the associated shrub and tree species.

Floral vasculature and its variation for carpellary supply inAnthurium(Araceae, Alismatales)

Introduction and AimsAnthuriumis the largest genus of Araceae, with 950 species distributed in the neotropics. Despite the great diversity of the genus, the knowledge of its floral vasculature is based on observations in only two species, viz.A. denudatumandA. lhotzkyanum, with remarkable variation in vascular carpellary supply: carpels are either vascularized by ventral bundles alone or by reduced dorsal bundles in addition to the ventral ones. Our main objective is to test this peculiar variation through a detailed anatomical study of the floral vasculature in taxa belonging to some sections ofAnthuriumdesignated as monophyletic groups in recent phylogenies.MethodsWe compare the floral vasculature of 20 neotropical species belonging to distinct sections ofAnthurium, using both light and confocal laser scanning microscopies.ResultsThe number and position of vascular bundles are constant within the tepals and stamens, regardless of the species and sections studied. However, the gynoecium vasculature exhibits variation between species belonging to the same or different sections. Our results reveal two patterns of vasculature: carpels vascularized by synlateral bundles alone (Pattern A) and carpels vascularized by both dorsal and synlateral bundles (Pattern B). Pattern A is shared by the majority of species studied here and corroborates the previous data in the literature. Pattern B occurs in three species:A. affine(Anthuriumsect. PachyneuriumseriesPachyneurium),A. obtusumandA. scandens(Anthuriumsect.Tetraspermium), described here for the first time for the genus.ConclusionsThe variation in the supply to the carpels inAnthuriumis corroborated here. However, our results in addition to those from the available literature suggest the existence of three patterns (A, B and C) of carpellary vasculature. Based on the recent phylogeny ofAnthuriumit is possible to notice that the three patterns of carpellary vasculature occur in representatives of Clade B and deserve to be investigated in a larger number of species. Pattern A could be a plesiomorphy for the genus and the occurrence of dorsal bundles could be a derived character. Our data contributes to the taxonomy and to the understanding of the floral evolution of the largest neotropical genus of Araceae.