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Review of the genus Lomachaeta Mickel, 1936 (Hymenoptera: Mutillidae) with new species and sex associations
No full textNew species and sex associations are proposed in the genus Lomachaeta Mickel, 1936. Six new species are described: Lomachaeta calamondin Williams, L. eironeia Williams, L. juanita Williams, L. meloi Williams, L. osita Williams, and L. warneri Williams. The previously unknown females of five species are described: L. beadugrimi (Pitts & Manley, 2004); L. chionothrix Pitts & Manley, 2004; L. hedera Williams & Pitts, 2009; L. hyphantria Pitts & Manley, 2004; and L. vacamuerta Williams & Pitts, 2009. The previously unknown male of L. vianai Casal, 1969 is described and L. megomicron Williams & Pitts, 2009 is placed as its synonym. Various new country and state records are presented. New keys and habitus pictures for all the 24 known species are provided. Copyright © 2019 Magnolia Press
Characterization of spermatogonial cells and niche in the scorpion mud turtle (Kinosternon scorpioides)
No full textUndifferentiated spermatogonia (A und ) or spermatogonial stem cells (SSCs) are committed to the establishment and maintenance of spermatogenesis and fertility throughout a male's life and are located in a highly specialized microenvironment called niche that regulates their fate. Although several studies have been developed on SSCs in mammalian testis, little is known about other vertebrate classes. The present study is the first to perform a more detailed investigation on the spermatogonial cells and their niche in a reptilian species. Thus, we characterized A und /SSCs and evaluated the existence of SSCs niche in the Kinosternon scorpioides, a freshwater turtle found from Mexico to northern and central South America. Our results showed that, in this species, A und /SSCs exhibited a nuclear morphological pattern similar to those described for other mammalian species already investigated. However, in comparison to other spermatogonial cell types, A und /SSCs presented the largest nuclear volume in this turtle. Similar to some mammalian and fish species investigated, both GFRA1 and CSF1 receptors were expressed in A und /SSCs in K. scorpioides. Also, as K. scorpioides A und /SSCs were preferentially located near blood vessels, it can be suggested that this niche characteristic is a well conserved feature during evolution. Besides being valuable for comparative reproductive biology, our findings represent an important step towards the understanding of SSCs biology and the development of valuable systems/tools for SSCs culture and cryopreservation in turtles. Moreover, we expect that the above-mentioned results will be useful for reproductive biotechnologies as well as for governmental programs aiming at reptilian species conservation. © 2018 Elsevier Inc
Chromosomal Mapping of Rex Retrotransposons in Tambaqui (Colossoma macropomum Cuvier, 1818) Exposed to Three Climate Change Scenarios
No full textGreenhouse gas emissions are known to influence the planet's temperature, mainly due to human activities. To allow hypothesis testing, as well as to seek viable alternatives for mitigation, the Intergovernmental Panel on Climate Change (IPCC) suggested 3 main scenarios for changes projected for the year 2100. In this paper, we subjected Colossoma macropomum Cuvier, 1818 (tambaqui) individuals in a microcosm to IPCC scenarios B1 (mild), A1B (intermediate), and A2 (extreme) to test possible impacts on their genome. We found chromosome heterochromatinization in specimens exposed to the A2 scenario, where terminal blocks and interstitial bands were detected on several chromosome pairs. The behavior of Rex1 and Rex3 sequences differed between the test scenarios. Hybridization of Rex1 resulted in diffuse signals which showed a gradual increase in the tested scenarios. For Rex3, an increase was observed in the A2 scenario with blocks on several chromosomes, some of which coincided with heterochromatin. Heterochromatinization is an epigenetic process, which may have occurred as a mechanism for regulating Rex3 activity. The signal pattern of Rex6 did not change, suggesting that other mechanisms are acting to regulate its activity. © 2019 S. Karger AG, Basel. Copyright: All rights reserved
Two new species of Enderleina Jewett (Plecoptera: Perlidae) from northern Brazil
No full textEnderleina Jewett, 1960 is a small genus of Perlidae with seven species occurring in Venezuela and northern Brazil. Specimens deposited in the Invertebrate Collection of the Instituto Nacional de Pesquisas da Amazônia (INPA), Manaus, Brazil, identified formerly as E. flinti Stark, 1989 (n = 3) and E. yano Stark, 1989 (n = 6), were determined to represent three taxa, two of which are new species. Both new species were collected in Amazonas State, Brazil and are distinctive within the genus due to their unique adult color patterns. The third taxon is represented by a female similar to E. khazeni Derka & Tierno Figueroa, 2013, the male of which was described from the nearby Gran Sabana, Venezuela. However, since the female of this species is not known, the specific identity of this female cannot be assigned specifically with confidence. In this paper, we describe two new species of Enderleina from Brazil, clarifying the specific status of the Enderleina specimens in the collection of INPA, and correcting the geographical distributions of E. flinti and E. yano. There are no valid records of these two species for Brazil. Currently, four species of the genus are known from Brazil. © 2019 Magnolia Pres
Acordo cooperativo entre a Universidade Federal do Amazonas - UFAM e o INPA
No full textConcessão de estágios obrigatórios, visando aprendizado, treinamento prático e aperfeiçoamento técnic
Ecohidrologia de Espécies Arbóreas de Terra Firme na Amazônia
Get PDFThe Amazon is the largest tropical forest in the world with great importance in the global biogeochemical cycles. Under climate change scenarios, a mechanistic understanding of the water cycle from individual trees to landscapes is needed to predict changes in the forest structure and function. In the Amazon basin, an estimated 25-50% of precipitation is recycled back to the atmosphere through forest transpiration. At the leaf level, transpiration flux is a function of vapor pressure deficit (VPD) and stomatal conductance (gs), according to Fick’s laws of diffusion. Also, leaf temperature (Tleaf), net radiation, and soil moisture are often considered important. In this study, we present in situ field observations of environmental (direct solar radiation, air temperature, and VPD) and physiological (sap velocity, stomatal conductance, and leaf water potential) variables and their correlations with Tleaf during the 2015-2016 ENSO and the regular seasons 2017 and 2018. In order to observe the interactions between physiological variables and fast-changing environmental conditions, we collected a high temporal frequency data (15-60 min) in two primary rainforest sites one located in the Central Amazon within the limits of the Experimental Station of Tropical Forestry (ZF-2) near the K-34 tower site, and another in the Eastern Amazon within the limits of the Tapajós National Forest at the the K-67 tower site. Our study shows that the interactions between the observed environmental and physiological variables can be explained by the hysteresis phenomena. The temporal difference between the peak of stomatal conductance (late morning to midday) and the peak of VPD (early afternoon) is one of the major regulators of the sap velocity hysteresis patterns. Also, for the first time, the hysteresis patterns between Tleaf and Tair were described. During the 2015-2016 ENSO, the differences between Tleaf and air temperature (Tair) reached almost 8°C, and generally, Tleaf was higher than Tair during the morning period to early afternoon, and lower than Tair during the late afternoon and night. With the leaf temperature data, it was possible to calculate the true VPD (ΔVPD), which is the pressure gradient between the substomatal cavity and the boundary layer of the air near the leaf surface. The complexity of the observed physiological and environmental variables that can affect the transpiration dynamics reinforces the importance of detailed analyzes during periods of climatic anomalies such as El Niño. The presented data can provide new perspectives for the improvement of current Earth System Models (ESMs).A floresta amazônica é a maior floresta tropical do mundo e possui grande importância nos fluxos globais de água e carbono, ocupando papel importante nos cenários futuros de mudança climática. Para se ter uma maior compreensão dos ciclos da água e do carbono, um melhor entendimento acerca das interações entre a fisiologia das plantas e fatores ambientais se faz necessário. Estima-se que cerca de 25-50 % da precipitação na bacia Amazônica é reciclada de volta para a atmosfera por meio da transpiração da floresta. Os mecanismos envolvidos na transpiração de espécies vegetais, embora sejam bem descritos na literatura, carecem de informações nas regiões tropicais, especialmente na Amazônia. O objetivo principal desta tese de doutoramento foi analisar a dinâmica da transpiração de árvores de terra firme da Amazônia e os fatores que a controlam. Para isto, o estudo foi conduzido em duas áreas distintas: uma na Amazônia Central dentro dos limites da Estação Experimental de Silvicultura Tropical (ZF-2) no sítio da torre K-34, e outra na Amazônia Oriental, dentro dos limites da Floresta Nacional do Tapajós, no sítio da torre K-67. Nos dois sítios as árvores-amostra foram sensorizadas numa alta intensidade temporal de coleta de dados (intervalos de 5 a 30 minutos) e também submetidas a experimentos de 12 horas de duração (curvas diárias). As variáveis obtidas foram: velocidade de seiva xilemática (cm hr-1), intensidade de luz direta (W m-2), temperatura foliar (°C), temperatura do ar (°C), déficit de pressão de vapor (VPD), potencial hídrico foliar (ΨL), condutância estomática (gs), além de parâmetros dendrométricos tais como o diâmetro à altura do peito (DAP), altura total (Ht) e a posição da árvore no dossel. Os dados foram coletados nos anos de 2015, 2016, 2017 e 2018, somando um total de quatro anos e 21 árvores estudadas. O biênio 2015-2016 esteve sob influência de um forte El Niño. Muitas análises utilizaram este período como comparativo, uma vez que as árvores foram expostas à níveis drásticos de seca e altas temperaturas. Verificou-se que a dinâmica da transpiração é governada pelo fenômeno de histerese. Esta histerese pode ser descrita como o resultado do deslocamento temporal da radiação solar direta, que tende a apresentar seus máximos perto do final da manhã, e o VPD que tende a apresentar seus valores máximos no começo da tarde. Além da transpiração, o fenômeno de histerese também rege a dinâmica de duas importantes variáveis: a temperatura do ar e a temperatura foliar. Com os dados de temperatura foliar é possível calcular o verdadeiro VPD (ΔVPD), sendo o gradiente de pressão entre a folha e a atmosfera. Além disto, verificou-se que durante o El Niño 2015-2016 a temperatura foliar diferiu da temperatura do ar numa ordem de até 8℃. A complexidade das variáveis fisiológicas e ambientais que podem afetar a dinâmica da transpiração, como demonstrado, reforça a importância de análises detalhadas durante períodos de anomalias climáticas como o El Niño. Estes dados fornecem novas perspectivas para o aprimoramento dos modelos climáticos atuais
PARÂMETROS ERITROCITÁRIOS DE TAMBAQUI Colossoma macropomum ANESTESIADOS COM ÓLEO ESSENCIAL DE Ocimum basilicum
No full textGas exchange, biomass allocation and water-use efficiency in response to elevated CO 2 and drought in andiroba (Carapa surinamensis, Meliaceae)
Get PDFProlonged droughts are predicted for some parts of the Amazon; however, it is still unclear how Amazonian trees will respond to water stress under the ongoing increase in CO 2 concentration. The aim of this study was to assess the effect of elevated CO 2 (eCO 2 ) and drought on photosynthetic rates, water-use efficiency, and biomass allocation in andiroba (Carapa surinamensis). The plants were grown in pots at ambient (400 ppm CO 2 ) and eCO 2 (700 ppm) at two water regimes, soil at 50% field capacity, FC (drought) and soil at 100% FC for 163 days. We measured light saturated photosynthesis on a mass basis (A sat-mass ), stomatal conductance to CO 2 on a mass basis (g sCO2-mass ), whole-plant water-use efficiency (WUE P ), biomass accumulation, specific leaf area (SLA) and total leaf area. At eCO 2 , A sat-mass increased 28% in well-watered plants and 93% under drought, whereas g sCO2-mass declined 39% in well-watered plants at eCO 2 , with no effect of drought on g sCO2-mass at eCO 2 . The total biomass gain improved 73% at eCO 2 and over CO 2 levels it was reduced (54%) by drought. WUE P improved (188%) at eCO 2 in well-watered plants and 262% under drought. SLA declined 23% at eCO 2 , but the effect of drought on SLA was null. On the contrary, total leaf area was greatly reduced (67%) by drought, but it was not affected by eCO 2 . The large increase in total biomass and the substantial improvement in WUE P under eCO 2 , and the sharp decline in leaf area under water stress widen our knowledge on the physiology of this important species for the forest management of large areas in the Amazon region. © SISEF
