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薛万琦  冯炎 《昆虫学报》2002,45(Z1):86-87
 报告了采自四川省二郎山的棘蝇属(Phaonia Robineau\|D esvoidy,1830)一新种和辽宁东部山区一新纪录种。新种命名为片尾棘蝇P.lamellicauda sp.nov.,应隶属于尖嘴棘蝇种团P.oxystoma\|group,其种团特征是髭角位于额角之 前;前中鬃强壮,后背中鬃3,小盾不带黄色,背侧片、前胸基腹片和后气门前肋裸;各足 胫节、中股和后股黄色,中胫无后腹鬃,后胫无端位后腹鬃。模式标本保存于沈阳师范学院 昆虫研究所。  相似文献   

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Helina sinaloensis n. sp. (Diptera: Muscidae) is described and illustrated from Mexico and Panama. The new species shows a unique combination of characters and can be distinguished from the other species of the genus by the prosternum with lateral cilia, pre-alar seta absent, anepimeron bare, katepimeron setulose, postalar wall setulose and scutellum with setulae on lateroventral margin.  相似文献   

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薛万琦  冯炎 《昆虫学报》2002,45(2):86-87
报告了采自四川省二郎山的棘蝇属(Phaonia Robineau Desvoidy,1830)一新种和辽宁东部山区一新纪录种。新种命名为片尾棘蝇P.lamellicauda sp.nov.,应隶属于尖嘴棘蝇种团P.oxystomagroup,其种团特征是髭角位于额角之前;前中鬃强壮,后背中鬃3,小盾不带黄色,背侧片、前胸基腹片和后气门前肋裸;各足胫节、中股和后股黄色,中胫无后腹鬃,后胫无端位后腹鬃。模式标本保存于沈阳师范学院昆虫研究所。  相似文献   

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Using X-ray diffractometry, the development of preferred orientation was studied in one species from each of the extant ratite families, from two moas and two tinamous and, as a preliminary comparison, from representative species from 16 of the other carinate orders. A preferred orientation begins to develop immediately after the start of shell deposition, and in all shells studied was one in which the (001) planes tend to lie parallel to the shell surface. The degree of (001) texture that develops in the ratite and tinamou shells is greater than that developed in the other carinate orders. Development in the ostrich, kiwi and tinamou is uninterrupted so that there is a very high degree of (001) preferred orientation at the exteriors of the shells. In the Emu, cassowary, rhea and the two moa species, a very high degree of (001) texture reverses gradually within the central layer of the shell, and in some species this is accompanied by the development of a very weak (104) preferred orientation. The weak (001) textures observed in the shells of the 20 species from the carinate orders other than the Tinamiformes develop slowly and without interruption through the shell; in four species a weak (104) texture develops simultaneously to that of the (001), forming a double texture similar to that already reported in the majority of shells of the domestic fowl.  相似文献   

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王文采 《植物研究》2017,37(5):641-644
描述了自重庆市江津区四面山发现的荨麻科赤车属一新种和楼梯草属二新种:(1)四面山赤车,与融安赤车近缘,区别在于新种的叶的二级脉较少,2枚雌花被片有短角状突起,以及长圆形瘦果;(2)稀柱毛楼梯草,可能与托叶楼梯草近缘,区别在于新种的叶较小,雌总苞苞片,以及雄、雌小苞片均在背面具龙骨状突起,柱头由只3~4根毛组成;(3)四面山楼梯草,与长尖楼梯草近缘,区别在于新种茎的顶端被短柔毛,雄头状花序的花序梗较短,以及雄总苞苞片呈条状船形,背面具龙骨状突起。  相似文献   

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Based on a further re-examination of loricate choanoflagellate species with detailed morphological (SEM/TEM) and molecular data of the SSU and LSU rRNA, the present study aims to give new insights for Stephanoeca cupula. In contrast to the original allocation within the family of tectiform reproducing species, morphological and molecular data of S. cupula sensu Leadbeater, 1972 points towards an affiliation within the nudiform reproducing family. Based on these new data, we here erect the nudiform genus Kalathoeca with its type species K. cupula gen. et comb. nov. Our data challenges morphological species assignments, as K. cupula shares its morphological lorica characteristics with tectiform reproducing species of Stephanoeca sensu stricto. Kalathoeca cupula is an interesting candidate for further investigating and understanding the evolutionary relationship of tectiform and nudiform reproducing species.Stephanoeca cupula sensu Thomsen, 1988 has been morphologically re-examined based on the renewed understanding of the morphological variability associated with S. cupula sensu Leadbeater, 1972 (=K. cupula), allowing us now to distribute the different morphological forms investigated within K. cupula and Pseudostephanoeca quasicupula.  相似文献   

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Stenommatomorphus hexarthrus gen. et sp. nov. (Dryophthoridae: Stromboscerinae) is described from the Late Eocene Rovno amber. This is the first fossil representative of the subfamily. The new genus is most close to Synommatus Pascoe, from which it differs in the pronotum and elytra less coarsely sculptured, the intervals not carinate, and the scutellum present.  相似文献   

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ABSTRACT The lorica of the tectiform choanoflagellate D. costata contains five categories of costal strips distinguishable from each other on the basis of morphology and patterning. Categories of strips include those forming the anterior transverse costa; the anterior, intermediate, and posterior costal strips, respectively, of the longitudinal costae and those constituting the posterior transverse costa. the distinctive morphology of each class of strips makes it possible to observe their location and orientation within the overall accumulation of strips at the top of the parent cell collar. In Diplotheca costata the orientation and positioning of the different categories of strips in an accumulation anticipates their orientation and imbrication in the mature lorica. Assembly of the lorica from an accumulation of strips involves lateral sliding of costal strips to constitute transverse costae and longitudinal sliding of strips to constitute longitudinal costae. the motive force for lorica assembly is provided by extension of the anterolateral tentacles.  相似文献   

10.
Misopates pontiense sp. nov. is described from one population located in the north-west of the Iberian Peninsula. It is an annual, living on charred soils. Its distinguishing characteristics include its seeds, which have a carinate dorsal face and an encircling rounded ridge with cylindrical papillae, but lack a median ridge on the ventral face. Morphological characters and taxonomic affinities are discussed.  相似文献   

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Rozko.  R Knuts.  L 《昆虫分类学报》1991,13(1):65-70
本文记述了采自中国东北沼蝇科的二个新种:Pherbellia orientalis sp.nov.属于该属的P.dorsata种团,其主要特征是翅部分为黑色,前足基跗节为鲜明的白色;Elgivamanchuricasp.nov.与该属的一个种E.divisa(Loew)相似,但可从新种光裸的前胸腹板和不同形状构造的雄性外生殖器予以区别。 新种的模式标本保存于德国波恩Alexander Koenig博物馆。  相似文献   

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在重庆市北碚区缙云山野外植物调查过程中,于海拔500~800 m的溪边阴湿沟谷中发现一种荨麻科植物,虽然该物种雌花序具花序托,但因其雌花花被片5枚,外面先端具角状突起,瘦果只具瘤状突起,更符合赤车属的特征,且结合分子系统学证据,该物种明显属于赤车属.该物种的特征在于其具花序托和总苞的雌花序,根据这一特征可将其置于头序赤...  相似文献   

15.

Unlike their reptile-like ancestors with continuous tooth replacement, mammals have evolved to replace each tooth either only once, or not at all. In previous large-scale comparative studies, it has been suggested that this tooth replacement only occurs from a successional dental lamina produced lingually to the primary tooth. This study aims to document the complete tooth development and replacement pattern of the tammar wallaby (Macropus eugenii). The tammar wallaby is a diprotodont marsupial, a group defined by their two procumbent lower incisors. To provide a comprehensive documentation of the spatio-temporal pattern of tooth development, we used Lugol’s Iodine staining and microCT scanning (diceCT) of embryos and pouch young into adulthood, resulting in high resolution 3D models for both soft and mineralised stages of development for all tooth positions. Our results reveal that the eponymous lower incisors are the successional generation at the third incisor locus, where the primary dentition initiates but never erupts. Furthermore, we track the development of the only replacement tooth, the permanent third premolar (P3), from initiation to eruption, and found it develops from the primary dental lamina, mesial to the dP3. This is contrary to the conventional view of lingual replacement from successional lamina in mammals. Our findings indicate that no functional tooth replacement occurs in the tammar wallaby, and expands the diversity of tooth replacement patterns found in mammals. We also conclude that since almost all marsupial and placental mammals produce replacement teeth from the distalmost deciduous premolar, this tooth should be considered homologous in these two groups.

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ALAN FEDUCCIA 《Ibis》1986,128(1):128-132
The scapula and coracoid of the first bird Archaeopteryx represents a highly specialized morphology approaching that of modern carinate birds, with the scapula meeting the coracoid at an angle of approximately 90o. The primitive condition of the avian scapula and coracoid is exhibited by the flightless ratites, birds exhibiting many other primitive characters of the skeleton, either retained from primitive ancestors or derived through neoteny. The fact that the scapulocoracoid of ratites is the primitive condition is confirmed by its presence in the embryos of certain birds, and its presence through neoteny in other unrelated birds that have secondarily evolved Sightlessness. This morphology of the primitive avian scapulocoracoid closely approaches that of theropod dinosaurs, such as Deinonychits , and may well indicate relationship between the two groups.  相似文献   

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A new tribe, new genus, and new species, Miocenocylas heeri gen. et sp. nov. from the Middle Miocene of Oeningen, Germany (Baden-Wurttemberg; Sarmatian, Upper Freshwater–Molasse Formation) are described. They differ from the tribe Cyladini in the free club articles, antennae inserted near the apex of the rostrum, procoxae located in the middle of the prosternum, the longer pronotum, and in the indistinct elytral striae.  相似文献   

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五种槽缝叩甲超微形态结构的比较研究 (鞘翅目:叩甲科)   总被引:1,自引:0,他引:1  
通过扫描电镜观察了槽缝叩甲属Agrypnus 5种的触角、前胸背板、中胸小盾片、鞘翅、前胸腹板、前胸侧板、中胸腹窝、跗节等部位的超微形态结构,提出了5种槽缝叩甲超微形态的区别特征,发现了槽缝叩甲体表鳞片毛上的纵脊数目和走向、中胸腹窝的结构与形状、体表刻点的形态等具有明显的种间差异,具有重要的分类学意义。讨论了硬结构昆虫扫描样品制备的程序,叩甲的叩头关节、触角槽、跗节槽的形成与功能,以及超微形态结构在叩甲分类上的价值等。  相似文献   

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ObjectivesConditioned medium (CM) from 2D cell culture can mitigate the weakened regenerative capacity of the implanted stem cells. However, the capacity of 3D CM to prime dental pulp stem cells (DPSCs) for pulp regeneration and its protein profile are still elusive. We aim to investigate the protein profile of CM derived from 3D tooth germs, and to unveil its potential for DPSCs‐based pulp regeneration.Materials and MethodsWe prepared CM of 3D ex vivo cultured tooth germ organs (3D TGO‐CM) and CM of 2D cultured tooth germ cells (2D TGC‐CM) and applied them to prime DPSCs. Influences on cell behaviours and protein profiles of CMs were compared. In vivo pulp regeneration of CMs‐primed DPSCs was explored using a tooth root fragment model on nude mice.ResultsTGO‐CM enhanced DPSCs proliferation, migration, in vitro mineralization, odontogenic differentiation, and angiogenesis performances. The TGO‐CM group generated superior pulp structures, more odontogenic cells attachment, and enhanced vasculature at 4 weeks post‐surgery, compared with the TGC‐CM group. Secretome analysis revealed that TGO‐CM contained more odontogenic and angiogenic growth factors and fewer pro‐inflammatory cytokines. Mechanisms leading to the differential CM profiles may be attributed to the cytokine–cytokine receptor interaction and PI3K‐Akt signalling pathway.ConclusionsThe unique secretome profile of 3D TGO‐CM made it a successful priming cocktail to enhance DPSCs‐based early pulp regeneration.  相似文献   

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Mammal teeth have evolved morphologies that allow for the efficient mechanical processing of different foods, therefore increasing dietary energy uptake for maintenance of high metabolic demands. However, individuals masticate foods with biomechanical properties at odds with the optimal function of a given tooth morphology. Here, we investigate tooth form and function using two quantitative 3D methods at different scales on the same individuals of nine bovid species. Dental topometry quantifies the gross morphology, and therefore, reflects evolutionary adaptive patterns. Surface texture analysis infers mechanical occlusal events, which reflect the actual tooth function, and is free from the influence of morphology. We found that tough foods can be satisfactorily exploited by grazing species with enamel ridge morphologies not more complex than those found in intermediate feeders and browsers. Thus, the evolution of enamel complexity is likely determined by a balance between adaptation and constraints. Wider enamel ridges seem to be a common functional trait in bovids to compensate for severe wear from abrasive foods and/or chipping from hard foods. Our results demonstrate that supposedly essential functional adaptations in tooth morphology may not be required to process food efficiently. This emphasizes the large plasticity between “optimal” morphology and the potential function of the tooth, and underscores the need to appreciate (apparently) maladaptive structures in mammalian evolution as nevertheless effective functioning units.  相似文献   

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