Clóvis Souza Bujes

A NEW SPECIES OF LIOLAEMUS FROM SOUTHERN BRAZIL (IGUANIA: TROPIDURIDAE)

We describe a new species of the genus Liolaemus from Rio Grande do Sul, Brazil. The morphology of the new species, L. arambarensis sp. nov, is compared to other species of Liolaemus of the “wiegmannii” group. The new species is distinguished from others members of this group by a dorsal color pattern with a medium dorsal white stripe and two dorsolateral stripes, two rows of juxtaposed brown marks resembling triangles, delimited by a white bar; nasal scales oriented dorsally; a complete row of dorsally oriented lorilabial scales between the subocular and supralabial scales; a moderate number of scales around the mid-body; flat temporal scales; flat head scales; and a transversely divided frontal. Liolaemus arambarensis sp. nov. is omnivorous, oviparous, and exhibits sexual dimorphism in color and size. Resumo Uma nova espécie do gênero Liolaemus do Rio Grande do Sul, Brazil é descrita neste trabalho. A morfologia da nova espécie, L. arambarensis sp. nov, é comparada às espécies de Liolaemus do grupo “wiegmannii.” A nova espécie se distingue dos demais membros desse grupo pelo padrão de coloração dorsal com uma faixa branca médio dorsal e duas faixas dorsolaterais, duas fileiras justapostas de marcas marrons lembrando triângulos, limitadas por uma barra branca; escamas nasais orientadas dorsalmente; um linha completa de escamas lorilabiais entre as escamas subocular e supralabial orientada dorsalmente; um número moderado de escamas ao redor do corpo escamas temporais planas; escamas da cabeça planas; e, frontal dividida transversalmente. Liolaemus arambarensis sp. nov. é omnívoro, ovíparo e com marcante dimorfismo sexual em cor e tamanho.

Annual activity of the lizard Liolaemus occipitalis (Squamata, Liolaemidae) in the coastal sand dunes of southern Brazil

The activity pattern of the small sand lizard, Liolaemus occipitalis Boulenger, 1885, was investigated in the coastal sand dunes at Quintao beach (Palmares do Sul, southern, Brazil), between September 1998 and August 1999. The results showed that L. occipitalis is active all along the year, but with variations in its daily and seasonal activity patterns associated to climatic changes in the habitat. Lizard activity pattern was distributed as follows: under the sand, burrowed (73%), under vegetation (14%), dislocation (7%) and basking (6%). Mean habitat temperatures (air and substrate) were significantly different. The results indicate that L. occipitalis is a thigmothermic and heliothermic species that regulates its body temperature through behavioral mechanisms, and that thermoregulation is mainly associated with substrate.

Supernumerary epidermal shields and carapace variation in Orbigny's slider turtles, Trachemys dorbigni (Testudines, Emydidae)

The epidermal plates of the carapace and plastron of 51 adults (38 females and 13 males), 07 immature individuals, and 46 hatchlings of the freshwater turtle Trachemys dorbigni (Duremil & Bibron, 1835), originated from the delta of Rio Jacui region, Rio Grande do Sul state, Brazil, were examined. The results showed that 7.7% of males, 10.52% of females, 14.28% of immature individuals, and 6.52% of the hatchlings presented a kind of anomaly on the shell, as well as a presence of supernumerary epidermal shields. Although the modification in the number of epidermal shields presents a high frequency in Testudines, these are the first descriptions of the variation in the pattern of carapacial scutation in eleven individuals from a population of T. dorbigni. The association of several environmental factors acting on the embryonic development of the individual may be responsible for the alteration of the pattern of carapacial scutation in this species.

Freshwater turtles of Rio Grande do Sul, Brazil: taxonomy, natural history and conservation

Rio Grande do Sul is the southernmost state of Brazil with peculiar flora and fauna associated to the morfoclimatic characteristics of the region. The diversity of Testudines from Rio Grande do Sul is represented by six freshwater turtle species and five sea turtle species. This study reports on the freshwater turtle diversity of Rio Grande do Sul, based on a compilation of published and some new data on their biology and conservation status.

Ritmo de atividade de Liolaemus Occipitalis boulenger (Sauria, Tropiduridae) na praia de Quintão, Rio Grande do Sul, Brasil

The activity rhythm of the lizard Liolaemus occipitalis Boulenger, 1885 was studied during the summer of 93 at the sand dunes of the Quintao beach, from 06:00-18:00h. During sunny days this lizard exhibited two peaks of activity (1000-1200h and 1400-1600h), and in the cloudy days it exhibited one peak of activity (1200-1400h). The number of burrows was observed and the different soil temperatures was compared with the rhythm of activity exhibited by the lizards. Rhythm of activity is determined mainly by soil surface temperatures.

Observações sobre o comportamento de Liolaemus occipitalis em cativeiro (Sauria, Tropiduridae)

Liolaemus occipitalis (Boulenger, 1885) is an abundant lizard lbundalong lhe coastal dunes of Rio Grande do Sul, Brazil. Fourteen individuais were manually captured in the dunes of Quintao beach (Palmares do Sul, Rio Grande do Sul) and studied in captivity from 23/VII/92 to 30/VII/93. They were kept in a terrarium with sand substrate and vegetation collected in their habitat. Snout-vent length (SVL) and wcighted were measured weekly. They received Tenebrio molitor (Linnaeus, 1758) worms as food; water was abundant. Combats between males for food and territory, and other behavioral displays were observed, like copulation and nesting behaviors. Growth curves for each lizard were analyzed.