990 resultados para Buys, Petrus, 1787-1853.


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The somatic and gonad productions of the cirolanid isopod Excirolana armata were analyzed by taking monthly samples from December 2003 to November 2005 on Una beach, So Paulo state (24A degrees S), southeastern Brazil. Sampling was performed along three fixed transects established from the base of the foredunes to the waterline. Weight-specific growth rate was used to estimate the E. armata somatic production for 2004 and 2005, separately. The gonad production was estimated based on the monthly reproductive potential (mean number of eggs/embryos per female x monthly abundance of ovigerous females with near-release broods) for 2004. The annual somatic production of E. armata population varied from 15.57 to 17.25 g AFDW m(-1) year(-1) and the somatic production/biomass ratio (P (s)/B) from 3.55 to 3.14 year(-1) for 2004 and 2005, respectively. The P (s)/B ratios were higher for males (4.02 and 3.19 year(-1) for 2004 and 2005) than for females (3.10 year(-1) for both years). The annual gonad production (P (g) = 1.07 g AFDW m(-1) year(-1)) contributed about 15 and 6% to the total production (P (s) + P (g)) of females and the population, respectively. The proportion of gonad to somatic production of females (P (g)/P (s)) increased with individual size (ca 90% in the 7.5 mm size class), and the annual weight-specific gonad production (P (g)/B ratio) was estimated to 0.24 year(-1). The high P (s)/B ratios estimated for E. armata derive from the fast growth of individuals and show the importance of this population to the energy flow on Una beach ecosystem. However, the low percentage of juveniles verified in this population and in other studies of populations of the genus Excirolana is discussed as an important source of underestimation of P (s)/B ratio.

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The final instar larva of Mnesarete pudica is described and illustrated based on reared specimens collected in Brazil. This species can be distinguished from others by presenting: a) five palpal and three premental setae; b) no posterodorsal hooks on abdominal segments; c) lateral spines only in S9-10. M. pudica is compared to other South American calopterygids and biological notes are presented.

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Ticks are classified into three families: Argasidae, Ixodidae, and Nutalliellidae. The taxonomy and phylogeny within Ixodidae are still discussed by the specialists, thus requiring further studies. Amblyomma cajennese and Amblyomma aureolatum (Brazil) belong to two species complexes known as “cajennese” and “ovale”, respectively, and are directly related to the transmission of the Brazilian spotted fever. This confirms the medical and veterinary significance of these species, as well as the need for further morphological studies that will bring a better understanding of their taxonomy, phylogeny, and control. In this context, the present study aimed to characterize the morphology of the male reproductive system of A. cajennese and A. aureolatum when unfed and after 4 days of feeding, thereby seeking to: (a) distinguish the two species or “complexes”, and (b) study an internal system which has the potential to be targeted by acaricides. Therefore, males from both species (unfed and after 4 days of feeding) were cold-anesthetized, dissected, and had their reproductive systems removed for histological analysis. The results showed that the morphology of the male reproductive system is generally similar between both species, like in other Ixodidae ticks, exhibiting a multilobed accessory gland complex related to seminal fluid secretion, a pair of vasa deferentia and a pair of testes housing germ cells (spermatocytes) in different stages. The main differences were found in the development of the accessory gland complex cells and germ cells, showing that the maturation of the male reproductive system starts later in A. aureolatum, when compared to A. cajennese. However, during the blood meal, A. aureolatum development is increased, thus making germ cell maturation and gland complex activity higher than in A. cajennese. This study shows the differences in the development of the male reproductive systems of both species, while providing information that can assist in the establishment of new control methods.

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A reassessment of the taxonomic status of Amblyomma cajennense based on the morphological analyses of ticks from the whole distribution area of the species resulted in the redescription of A. cajennense, the validation of 2 species which had been reduced to synonymy in the past, Amblyomma mixtum and Amblyomma sculptum, and the description and definition of 3 new species, Amblyomma tonelliae n. sp., Amblyomma interandinum n. sp., and Amblyomma patinoi n. sp. This study provides descriptions and redescriptions, scanning electron microscopic and stereomicroscopic images, updated synonymies, information on geographical distributions, and host associations for each of the 6 species. Amblyomma cajennense s.s. is found in the Amazonian region of South America, A. interandinum is reported from the northern part of the Inter-Andean valley of Peru, A. mixtum is present from Texas (U.S.A.) to western Ecuador, A. patinoi occurs in the Eastern Cordillera of Colombia, A. tonelliae is associated with the dry areas of the Chaco region which spans from central-northern Argentina to Bolivia and Paraguay, whereas A. sculptum is distributed from the humid areas of northern Argentina, to the contiguous regions of Bolivia and Paraguay and the coastal and central-western states of Brazil.

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Der vorliegende Beitrag stellt die 1604 verfasste und bislang unveröffentlichte Autobiographie des kurtrierischen, jülich-bergischen und nach dem Zerfall der Vereinigten Herzogtümer Jülich-Kleve-Berg pfalz-neuburgischen Rates Petrus Simonius Ritz (1562-1622) vor. Seit 1595 stand der Schreiber in jülich-bergischen Diensten und nahm bis zu seinem Tod an fast allen bedeutsamen Ereignissen der damals angespannten politischen Situation am Niederrhein teil. Bei Beachtung der Klischees, die Simonius in seiner Selbstdarstellung verwendet, dürfte die mitunter sehr detaillierte und aufmerksame Beschreibung seiner alltäglichen Wahrnehmungen den besonderen Wert der Aufzeichnungen ausmachen. Er erzählt von seinem Bildungsweg, von Heirat, Krankheit und dem Tode seiner ersten Frau, der anschließenden Wiederverheiratung und natürlich auch vom Alltag bei Hofe.