摘要:

Immature stages ofRogenhofera bonaerensis(Del Ponte, 1939) are described and illustrated. Seasonality data of each stages are included.

ISSN:0165-0521    

DOI:10.1080/01650529109360844

出版商:Taylor & Francis Group    

年代:1991

数据来源: Taylor

摘要:

In southeastern Brazil the leptodactylid frogsLeptodactylus fuscusandPhysalaemus fuscomaculatusenter dormancy during the dry season. Oxygen uptake was measured in awake and dormant groups of both species in a temperature range at which these frogs are usually exposed throughout the year. Oxygen uptake was lower for dormant groups at high temperature, and a lack of response to temperature was reported between 20–25C in the dormant group of both species. This temperature‐intensitive range can be considered an adaptive feature to save fat reserves during dormancy.

ISSN:0165-0521    

DOI:10.1080/01650529109360845

出版商:Taylor & Francis Group    

年代:1991

数据来源: Taylor

摘要:

Variations of density and of population structure ofOctodon degusin the area of National Park “La Campana”, two habitats with different grade of intervention during the time of breeding in two consecutive years, are shown. The density of this rodent is in inverse relation to the degree of alteration of the habitat, showing its sensibility to the changes of the habitat. At the end of winter (August/September) the population would have its lowest density. Its maximun expression is obtained at the beginning of summer (December) coinciding with the breeding period. The relationship between immature adult from one year to the other shows a close relation. However, the variations observed during the same year are due to the recruit of the immature of the two offsprings that the rodent produces. When demand is greatly reduced from February to May, the palm fruit is an important nutricional help. But it has not been well defined quantitatively. The other members of the community of micro‐mammals show the same tendency ofOctodon degus:a low density at the end of winter that increases as spring advances.

ISSN:0165-0521    

DOI:10.1080/01650529109360846

出版商:Taylor & Francis Group    

年代:1991

数据来源: Taylor

摘要:

The macrobenthic fauna of lago Escondido (Río Negro, Argentina) has been sampled from May to November, 1987. Samples were collected with an Ekman‐Birge dredge (263 cm2), along four transects with an 1 meter depth interval. Some physical and chemical parameters were also taken. From the 28 identified taxa, chironomid larvae exhibited the highest values both in species richness and abundance. The most abundant chironomids werePolypedilumsp. (3354 ind./m2) andNimbocerasp. (2312 ind./m2) in the 0–1 m interval. The higest density was observed in the littoral zone (0–5 m), whereSchaenoplectus californicusandPotamogeton linguatusgrow; in which the maximum value was 8224 ind./m2between 0 and 1 m. The lowest density (303 ind./m2) was detected in the zone without vegetation (7–8 m). The faunistic composition of lake Escondido showed some differences with similar temperate lakes in the Northern hemisphere and Australia, e.g. it lacks the predaceous chaoborid larvae; and similarities with the New Zealand lakes but with higher species richness of chironomids.

ISSN:0165-0521    

DOI:10.1080/01650529109360847

出版商:Taylor & Francis Group    

年代:1991

数据来源: Taylor

摘要:

Habitat, activity period, food, predators, and defensive behavior are briefly described for five species of snakes with coral‐snake pattern, sympatric in southeastern Brazil:Micrurus frontalis, M. lemniscatus, Erythrolamprus aesculapii, Oxyrhopus guibei, andSimophis rhinostoma. Defensive behaviors were analyzed by numerical methods in order to evaluate the degree of similarity between these species. The similarity between defensive displays is supposed to be due either to phylogenetic affinity or to mimetic convergence.

ISSN:0165-0521    

DOI:10.1080/01650529109360848

出版商:Taylor & Francis Group    

年代:1991

数据来源: Taylor

摘要:

From the six previously in Colombia reportedAndogyrusspecies,A. buqueti(Aubé, 1838) was proved. For this species details to the habitat and remarks on the behaviour of the egg‐morphology and on socialization with other streamdwellers are announced.

ISSN:0165-0521    

DOI:10.1080/01650529109360849

出版商:Taylor & Francis Group    

年代:1991

数据来源: Taylor

摘要:

Five species of the antlike jumping spiderSynemosynawere collected in northern Colombia:S. americana(Peckham and Peckham), 5.ankelin, sp.,S. aurantiaca(Mello Leitáo),S. invernarn. sp. and S.lucasi(Taczanowski). A key to the species is provided.

ISSN:0165-0521    

DOI:10.1080/01650529109360850

出版商:Taylor & Francis Group    

年代:1991

数据来源: Taylor

摘要:

Twenty one species of lizards (four families) were found in the region of Balbina Hydroelectric Station, Uatumã river, 60 km east of Presidente Figueiredo, Amazonas State, Brazil. Most lizards are exclusive forest dwellers exploring horizontal, vertical, or both spaces. Twenty species are diurnal and one is nocturnal; no marked seasonal difference in activity was observed. Except for the known food specialistsIguana iguana(leaves) andPlica umbra(ants), and the omnivorousTupinambis nigropunctatus, all other species seem to be arthropod generalists. Three guilds with widely overlapping resource utilization are evident. These patterns are very similar to those found in other localities in the Amazon Basin, probably because of the similarity among their herpetofaunas and structural habitats. A brief review of the hypothesis that tries to explain how the members of these complex assemblages coexist shows that, although some authors suggest that competition is weak or inexists in these assemblages, there is no published study demonstrating the role of competition and/or predation in an Amazonian lizard community.

ISSN:0165-0521    

DOI:10.1080/01650529109360851

出版商:Taylor & Francis Group    

年代:1991

数据来源: Taylor

ISSN:0165-0521    

DOI:10.1080/01650529109360843

出版商:Taylor & Francis Group    

年代:1991

数据来源: Taylor