7 resultados para Zootermopsis nevadensis


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The structure of the spermatheca was investigated in specimens of five termite families with the aid of light microscopy. In longitudinal section, the spermatheca of Zootermopsis nevadensis (Termopsidae) showed the shape of an umbrella with a secretory portion and duct. The other termite species, which belong to the families Kalotermitidae, Serritermitidae, Rhinotermitidae and Termitidae showed a spermatheca constituted only by the secretory portion. This structure was an elongate, fingerlike tube with a recurved and blind extremity. The spermatheca wall was composed of a single epithelium formed by class 3 secretory cells with a lumen lined by cuticle. The cuticle was thin and smooth or thick with digitiform projections in the species examined. All the termite females showed bundles of musculature outside of the spermatheca.

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Se publican las primeras citas conocidas para Crocus nevadensis Amo & Campo ex Amo en la provincia de Toledo. Se muestran fotografías tomadas en la fecha y lugar de los hallazgos.

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[ES] El grado de melanismo en Lacerta lepida, definido por la presencia de escamas negras en el dorso, es un carácter que varía a lo largo de su área de distribución ajustándose bien a las condiciones climáticas de las regiones donde está presente. Los lagartos ocelados son más oscuros en zonas con bajo número de horas de sol al año en el noroeste ibérico, y carecen de escamas negras en aquellas zonas del sureste donde las precipitaciones son menores. Se ha cartografiado la presencia de lagartos con escamas negras o sin ellas para relacionar este carácter con la distribución de Lacerta lepida nevadensis, ya que es el que mejor define a los adultos de esta subespecie.

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草白蚁科Hodotermitdae原白蚁亚科Hodotermopsinae目前仅知Zootermopsis,Archotermopsis和Hodotermopsis3个属。前1属分布于西半球的北美洲,后2属分布于东半球的东洋区。原白蚁属Hodotermopsis广泛分布于我国长江以南的丘陵地带,以及越南北部和日本南部的一些岛屿。这类白蚁取食木材,危害多种林木,一般生活在亚热带潮湿森林内,俗称湿木白蚁Dampwoodtermites。原白蚁属Hodotermopsis是N.Holmgren于1911年建立的,属于比较原始的类群。常筑巢于原木内,蚁巢结构比较简单,群体品级的分化亦处于较原始状态。幼蚁担负全巢劳作替代工以职能,故有拟工蚁之称。兵蚁的形态与成虫和幼蚁近似,其头部特别是个体小的头型近圆形,扁平;上颚粗壮,左右内缘多齿;触角节数多于20节;附节5节;尾须分节等。这些性状均保留了原始类型的特点。原白蚁形态变化颇大,有时似呈连续的梯度变异。如果采得少数个体,很容易将不同地方的种群或不同个体误定为不同种。原白蚁的模式种是H.sjbstedtiHolmgren。1912年,H0lmgren又以兵蚁右上颚齿的尖形与...

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The Middle Ordovician Sunblood Formation in the South Nahanni River area, District of Mackenzie, comprises mainly limestones and dolostones of intertidal and shallow subtidal origin as indicated by the presence of desiccation polygons, fenestral fabric, and oncolites. The study of well preserved, silicified trilobites from low diversity, Bathyurus-dominated, Nearshore Biofacies faunas of Whiterockian and Chazyan age collected in six stratigraphic sections through the Sunblood Formation permits the recognition of three new Whiterockian zones, and two previously established Chazyan zones. The Bathyurus mackenziensis, Bathyurus sunbloodensis, and Bathyurus margareti zones (Whiterockian), together with the Bathyurus nevadensis and Bathyurus granu/osus zones (Chazyan) represent the Nearshore Biofacies components of a dual biostratigraphic scheme that considers both temporal and spatial distribution patterns, and are compositionally distinct from faunas in correlative strata around North America that represent other biofacies. Twenty-six species belonging to eighteen genera are described and illustrated. Ludvigsenella ellipsepyga is established as a new bathyurine genus, in addition to four new species of Bathyurus : Bathyurus mackenziensis, Bathyurus sunbloodensis, Bathyurus margareti and Bathyurus acanthopyga. Other genera present are: Basilicus, Isote/us, ///aenus, Bumastoides, Fail/eana, Phorocepha/a,Ceraurinella, Acanthoparypha, Xystocrania, Cydonocephalus, Ectenonotus, Pseudomera, Encrinuroides, Calyptaulax, Amphilichas and Hemiarges.

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Termites are social cockroaches and this sociality is founded on a high plasticity during development. Three molting types (progressive, stationary and regressive molts) are fundamental to achieve plasticity during alate/sexual development, and they make termites a major challenge to any model on endocrine regulation in insect development. As the endocrine signatures underpinning this plasticity are barely understood, we studied the developmental dynamics and their underlying juvenile hormone OH) titers in a wood-dwelling termite. Cryptotermes secundus, which is characterized by an ancestral life style of living in dead wood and individuals being totipotent in development. The following general pattern elements could be identified during winged sexual development (i) regressive molts were accompanied by longer intermolt periods than other molting types, (ii) JH titers decreased gradually during the developmental transition from larva (immatures without wing buds), to nymph (immatures with wing buds), to winged adult, (iii) in all nymphal stages, the JH titer rose before the next molt and dropped thereafter within the first week, (iv) considerable variation in JH titers occurred in the midphase of the molting cycle of the 2nd and 3rd nymphal instar, inferring that this variation may reflect the underlying endocrine signature of each of the three molting types, (v) the 4th nymphal instar, the shortest of all, seems to be a switch point in development, as nymphs in this stage mainly developed progressively. When comparing these patterns with endocrine signatures seen in cockroaches, the developmental program of Cryprotermes can be interpreted as a co-option and repetitive use of hormonal dynamics of the post dorsal-closure phase of cockroach embryonic development. (C) 2012 Elsevier Ltd. All tights reserved.

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In an attempt to reveal the relationships between alkaloid biosynthesis and phylogeny, we investigated by GC–MS the alkaloid patterns of 22 species and 3 hybrids (from 45 locations) from seven main sections of the genus Narcissus (Amaryllidaceae). The results indicate that the first alkaloids to evolve in the genus Narcissus were of the lycorine- and homolycorine-type. The alkaloid pattern of the Nevadensis section supports its recent separation from the Pseudonarcissus section. The plants of Narcissus pallidulus (Ganymedes section) show a predominance of Sceletium-type compounds, which are quite rare in the Amaryllidaceae family. Two successful evolutionary strategies involving alkaloid biosynthesis and leading to an expansion in taxa and occupied area were determined. Firstly, a diversification of alkaloid patterns and a high alkaloid concentration in the organs of the large Narcissus species (in the Pseudonarcissus section) resulted in an improved chemical defence in diverse habitats. Secondly, both plant size and alkaloid biosynthesis were reduced (in the Bulbocodium and Apodanthi sections) relegated to dry pastures and rocky places.