9 research outputs found

    A Review of the fossil record of turtles of the clade Baenidae

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    The fossil record of the turtle clade Baenidae ranges from the Early Cretaceous (Aptian—Albian) to the Eocene. The group is present throughout North America during the Early Cretaceous, but is restricted to the western portions of the continents in the Late Cretaceous and Paleogene. No credible remains of the clade have been reported outside of North America to date. Baenids were warmadapted freshwater aquatic turtles that supported high levels of diversity at times through niche partitioning, particularly by adapting to a broad range of dietary preferences ranging from omnivorous to molluscivorous. Current phylogenies place Baenidae near the split of crown-group Testudines. Within Baenidae three more inclusive, named clades are recognized: Baenodda, Palatobaeninae and Eubaeninae. A taxonomic review of the group concludes that of 49 named taxa, 30 are nomina valida, 12 are nomina invalida and 7 are nomina dubia

    On the development of the brown spider Loxosceles gaucho Gertsch (Araneae, Sicariidae): the nympho-imaginal period

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    Observations of the developmental biology of Loxosceles gaucho Gertsch, 1967, the brown spider of southeastern Brazil are scarce. The present study reports the method of individualized rearing of 18 populations of L. gaucho, kept in laboratory under varied diet conditions, and characterizes their nympho-imaginal period as well as factors related to their reproduction. Females built the first egg sac about 20 days after copulation and nymphs hatched 40 days after the laying date. Average offspring was 61.3 spiderlings and females usually built three to four successive egg sacs in a period of five to seven months. First nymphs initiated their predatory activity between the 5th and 8th days after hatching and the majority reached adulthood within six moults (range of five to eight) in approximately 15 to 17 months (male) and 15.5 to 18 months (female). The average sex ratio equaled 1.0:1.7 (male:female). The wide individual variability of this species intermoult intervals is herewith expressed by the "intermoult rate", which was fairly uniform for both intra and interpopulations and gives a relevant aspect for a general idea of the life cycles of spiders

    Effects of gamma radiation on the sterility and behavioral quality of the caribbean fruit fly, Anastrepha suspensa (Loew) (Diptera:Tephritidae) Efeitos da radiação gama na esterilização e comportamento da mosca-do-caribe, Anastrepha suspensa (Low) (Diptera:Tephritidae)

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    Pupae of Anastrepha suspensa (Loew) were irradiated 2 days before adult eclosión in an air atmosphere with 15, 20, 25, 30, 50 and 70 Gy of gamma radiation (Co-60). The radiation effects on sterility and other parameters of quality and behavior of males and females of caribfly were established. Males became fully sterile with a dose of 50 Gy and females laid no eggs when exposed to 25 Gy. Radiation had no significant effect on adult eclosion, sex ratio, flight ability and irritability, but female mortality was affected significantly by radiation, showing higher survival rates in low dosage treatments. The mating behavior of the males was reduced significantly by increasing the radiation doses.<br>Pupas de Anastrepha suspensa (Loew) foram irradiadas dois dias antes da emergência dos adultos em atmosfera de ar com as doses de 15, 20, 25, 30, 50 e 70 Gy de radiação gama (Co-60). Foram avaliados os efeitos da radiação sobre a esterilidade e outros parâmetros de qualidade e comportamento de machos e fêmeas de mosca-do-caribe. Machos tornaram-se totalmente estéreis com uma dose de 50 Gy e as fêmeas não ovipositaram quando expostas a 25 Gy. A radiação não teve efeito significativo sobre a taxa de emergência de adultos, na razão sexual, na habilidade de vôo e na irritabilidade desses insetos. Somente a mortalidade das fêmeas foi afetada significativamente pela radiação, causando unia maior sobrevivência nas dosagens mais baixas. A atividade de acasalamento dos machos foi reduzida significativamente com o incremento da dosagem de radiação
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