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1.
2.
A new nematode genus, Nothacrobeles, is proposed in the subfamily Acrobelinae. Four new species are described and one new combination made. The five species exhibit a progression from short-to-long, bifurcate, elaborately fringed labial probolae, the longest probolae resembling those of species of Acrobeles.  相似文献   
3.
Judy L. Stone 《Oecologia》1996,107(4):504-512
In this paper I report components of effectiveness for pollinators of a tropical distylous shrub, Psychotria suerrensis (Rubiaceae), which is visited by a variety of bees, wasps, and butterflies, and by two species of hummingbirds. In the field, I measured the following components of effectiveness: frequency of visits, evenness of visits across plants, and diurnal pattern of visits. I also used flight-cage experiments to compare pollentransfer abilities of euglossine bees and heliconiid butterflies. Euglossine bees visited more frequently, visited earlier in the day, and visited a higher proportion of plants in the population than did other taxa. In flight cage experiments, bees and butterflies transferred similar amounts of pollen overall, but bees transferred significantly more inter-morph (compatible) pollen. For each component measured, euglossine bees appeared to be the most effective pollinators.  相似文献   
4.
The young sporocysts had a wrinkled sporocyst wall, numerous papillae on the wall surface and the wall was granular and porous. In the itraconazole-treated culture, the walls of the young sporocysts were also wrinkled, but the characteristic papillae were replaced by larger lumps which were densely packed and coated the entire surface of the sporocyst wall. The mature sporocysts walls were smooth and possessed numerous papillae. In the itraconazole-treated culture, the walls of mature sporocysts walls were also smooth but possessed densely packed larger lumps instead of papillae. At higher magnification, each of the lumps were found to consist of numerous globules. No pores were observed as they were in the normal sporocyst wall.  相似文献   
5.
We present a simplified version of a previously presented model (Camazine et al. (1990)) that generates the characteristic pattern of honey, pollen and brood which develops on combs in honey bee colonies. We demonstrate that the formation of a band of pollen surrounding the brood area is dependent on the assumed form of the honey and pollen removal terms, and that a significant pollen band arises as the parameter controlling the rate of pollen input passes through a bifurcation value. The persistence of the pollen band after a temporary increase in pollen input can be predicted from the model. We also determine conditions on the parameters which ensure the accumulation of honey in the periphery and demonstrate that, although there is an important qualitative difference between the simplified and complete models, an analysis of the simplified version helps us understand many biological aspects of the more complex complete model. Corresponding author  相似文献   
6.
The pollination biology and breeding systems ofEriotheca pubescens andE. gracilipes have been studied. These two species occur as trees in cerrado vegetation, the neotropical savannas of Central Brazil, with partially sympatric distributions. They have similar phenology and floral structure, although the flowers ofE. pubescens are larger. Both species have nectar flowers pollinated by largeAnthophoridae bees but the main pollinators of each species differ in size. The species have markedly different breeding systems: late-acting self-incompatibility inE. gracilipes and apomixis stimulated by pollination inE. pubescens.  相似文献   
7.
Summary Juvenile hormone III content and ecdysteroid titer were analyzed for larval and pupal development of the stingless bee,Scaptotrigona postica depilis. Castespecific differences in juvenile hormone III content were detected at three developmental phases: at the transition from the fourth to the fifth larval stadium, in the spinning phase of the fifth larval stadium, and shortly after the imaginal moult. During the fifth larval stadium, juvenile hormone content closely reflects corpora allata activity. Juvenile hormone synthesis may thus be responsible for the elevated hormone titer in spinning-phase queen larvae, a phase of known sensitivity for induction of queen characters by exogenous juvenile hormone. For ecdysteroids, two phases of caste-specific differences were found: in the pre-pupal phase, and shortly after the imaginal moult. In both periods the titer in queens is distinctly higher compared to workers.Abbreviations Im imago 1 day after eclosion - L3, L4, L5 larval instars 3, 4, and 5 - L5F1, L5F2 substages of feeding phase in fifth larval instar - L5S1, L5S2, L5S3 substages of spinning phase in fifth larval instar - PP1, PP2 substages of prepupal phase - Pw white eyed pupa - Pp pink eyed pupa - Pr red eyed pupa - Pd dark eyed pupa - Pdl, Pdm, Pdd dark eyed pupa with progressive tanning of cuticle - RIA radioimmunoassay  相似文献   
8.
Verrucaria schaereri (Fr.)Nyl. is accorded generic status asPlacocarpus Trev. emend.O. Breuss. The main differences between the two genera concern the thallus anatomy and the spores which are halonate inPlacocarpus. The following new combinations are proposed:Placocarpus schaereri (Fr.)O. Breuss andPlacidiopsis cinerascens (Nyl.)O. Breuss.  相似文献   
9.
球针壳属一新种和一新组合   总被引:1,自引:0,他引:1  
本文报道了球针壳属(Phyllactinia)的一个新种和一个新组合,即寄生于杜鹃花科(Ericaceae)吊钟花属(ENkianthus)灯笼花(E.chinensis Franch)上的灯笼花球针壳(Phyllactiniaenkianthi z.y. zhao sp. nov.)和寄生于茶藨子科(Grossulariaceae)茶藨子(Ribes sp.)上的茶藨子球针壳(Phyllactinia ribesii(Jacz.)z. y. zhao comb. nov.)。上述新分类单位均有汉文和拉丁文描述,新分类单位与近似种有汉文讨论。  相似文献   
10.
Restriction fragment length polymorphism (RFLP) of the total DNA ofBipolaris andCurvularia species was analysed using arbitrarily chosen genomic clones of DNA fromCurvularia lunata andBipolaris maydis as probes. Clear differences among species in both genera, resulting in different banding positions, were obtained with some probe-enzyme combinations. Intraspecific polymorphism in banding positions with these probe-enzyme combinations was slight. These analyses allow discrimination between the species. DNA fingerprinting with intrageneric probes is a potentially useful tool for species separation and identification inBipolaris andCurvularia when coupled with another characteristic such as conidial morphology.Curvularia aeria comb. nov. was proposed forCurvularia lunata var.aeria on the basis of differences in RFLP banding patterns and differences in conidial morphology.  相似文献   
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