Use of cacti as heat sources by thermoregulating Mabuya agilis (Raddi) and Mabuya macrorhyncha Hoge (Lacertflia, Scincidae) in two restinga habitats in southeastern Brazil

Lizards may benefit from gain of heat from contact with the substrate via conduction. In this study, evidence that the lizards Mabuya agilis (Raddi, 1823) and Mabuya macrorhynclui Hoge, 1946 (Scincidae) inhabiting two restinga habitats in southeastern Brazil (Grussaf, Rio de Janeiro and Praia das Neves, Espfrito Santo), may shift microhabitat preferences along the day, and that such shifts may be related to the use of cacti surfaces as direct sources of heat is presented. For both species, body temperature (Tb) was always significantly correlated (p < 0,05) with air temperature (Ta). Tb was significantly correlated (p < 0,0.5) with substrate temperature (Ts) for M. agilis collected on cacti, but not for specimens collected on the ground. For M. macrorhyncha collected on cacti, both Ta and Ts were more important in conjunction than separately, in explaining lizard Tb. Use of cacti as perches by M. agilis was more frequent during late afternoon when environmental temperatures are declining, but such a trend was not evident for M. macrorhynclui. We suggest that the use of cacti as direct heat sources may be more evident in the ground-dwelling M. agilis than in the scansorial M. macrorhynclui

Ecology of Mabuya agilis (Raddi) (Lacertilia, Scincidae) at the restinga of Grumari, Rio de Janeiro, southeastern Brazil

Some aspects of the ecology of the skink Mabuya agilis (Raddi, 1823) at the restinga habitat of Grumari, in Rio de Janeiro, Brazil are studied. Most of the lizards were first sighted on the ground, though a few were using perches (mainly cacti) up to 30 cm high. Mean body temperature in activity was 33.1 ± 2.4ºC and was significantly correlated to air temperature. There was sexual dimorphism in size (snout-vent length - SVL), with females growing larger than males. Frequency of broken tails was high overall (83%) and did not differ between sexes. Females and males are sexually mature at 49 mm and 47 mm SVL, respectively. Brood size averaged 3.2 ± 1.0 (range 1-5) and was positively and significantly related to female SVL (r = 0.65, p = 0.001). Relative clutch mass (RCM) of seven gravid females averaged 0.250 ± 0.042, being relatively low compared to those of other congeners. The diet of M. agilis was composed basically of arthropods, with relatively large and soft-bodied arthropods such as spiders, caterpillars and homopterans being the most important prey. The results of our work confirm and expand the knowledge of ecological tendencies previously observed for M. agilis in other areas

Capim-piatã adubado com fontes de fósforo de diferente solubilidade em água

The development of piatã grass fertilized with phosphorus sources with different solubilities in water was evaluated. The experiment was developed in the unit of Aquidauana of UEMS, MS, from February to August, 2012. Four treatments were evaluated: control (without phosphorus fertilization), slow solubility, fast solubility (readily available), and mixed solubility sources of phosphorus (FH Pasture(r)). It was adopted a randomized blocks design with four blocks and four replicates in a total of 16 pastures (0.5 ha each one). Measurements were performed weekly to evaluate structural characteristics and morphogenic variables of the plants. Data were submitted to a variance analysis according to the model. When necessary, the means of treatments with different phosphorus fertilizer sources were compared with the control using the Dunnett test and with other treatments by using student's t test. The significance level of 5% was adopted in all analysis. No significant effect was observed (P<0.05) in the evaluated traits in the first year of the experiment