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1.
A revision of Leptotheca Thélohan, 1895 is presented. The boundaries that separate Leptotheca from Ceratomyxa Thélohan, 1892 and Sphaerospora Thélohan, 1892 are vague and have been highlighted as an area of concern within myxosporean classification. A survey of the literature revealed 63 species that are currently assigned to Leptotheca and a further 11 species that have been relegated as synonyms in Ceratomyxa, Sphaerospora or Myxobolus Bütschli, 1882. The placement of some species in the genus is unclear and demonstrates the need for a revision. The type-species of Leptotheca (L. agilis Thélohan 1892) has many Ceratomyxa-like characters, such that a minor amendation of the diagnosis of Ceratomyxa will then accept the type-species of Leptotheca, rendering the latter genus its synonym. We propose the suppression of Leptotheca, with all species currently assigned to that genus reassigned to Ceratomyxa, Ellipsomyxa K?ie, 2003, Myxobolus or Sphaerospora on the basis of appropriate morphological and biological traits. The diagnoses of Ceratomyxa and Ellipsomyxa are amended appropriately. Molecular analysis may change the placement of some species in the future; however, the aim of this review was to eliminate the ambiguity of assignment of species in the genera Leptotheca, Ceratomyxa and Sphaerospora by suppressing Leptotheca.  相似文献   

2.
Paraorygmatobothrium taylori n. sp. (Tetraphyllidea: Phyllobothriidae) is described from the Australian weasel shark Hemigaleus australiensis White, Last & Compagno in Moreton Bay, off Queensland, Australia. The new species differs from 10 of the 11 described species of Paraorygmatobothrium Ruhnke, 1994 by the possession of prominent, semicircular bothridial muscle bands. From Pbarberi Ruhnke, 1994, with which it shares the bothridial muscle bands, it differs in the possession of a cephalic peduncle and vitelline follicles that extend almost to the mid-line of the proglottis and are reduced, rather than completely interrupted, at the level of the ovary. P. janineae Ruhnke, Healy & Shapero, 2006 is recorded from its type–host but in a new locality, Moreton Bay, off Queensland, Australia. P. taylori is the third species of the genus recorded from the Hemigaleidae in Australian waters. Three of the eight known hemigaleid species are now recorded to harbour this genus, and three different species are now known from the two hemigaleids found in Australian waters.  相似文献   

3.
Zusammenfassung Ein Paar des HonigsaugersNectarinia kilimensis wurde in der Brutzeit beim Nestbau 21 Stunden beobachtet. Über die Bauaktivität gibt Abb. 2 Aufschluß. 140 von 144 Anflügen mit Nistmaterial waren auf 8 Stunden von 8h–16h konzentriert. Das Nistmaterial bestand fast ausschließlich aus Halmen, Pflanzenwolle und Spinnweben; dieses Material wurde von Anfang an abwechselnd verwendet. Nur das hat gebaut. Die Baumethoden werden beschrieben, ebenso verschiedene Balzhandlungen des . Der Nestbau dauerte 4 1/2, beim folgenden Nest 3 1/2 Tage.Beim Brüten waren Schnabel und Oberkopf des sichtbar. Während der Bauzeit wurde ein ausgeflogenes juv. nur vom gefüttert. Als es mindestens 17 Tage alt war, wurde es vom , 6 Tage später auch vom aggressive gejagt, doch war dieses juv. mehr als 3 Wochen nach dem Ausfliegen noch im Revier.
Day-time activity, nest-building method and breeding behaviour of Bronze SunbirdNectarinia (Aidemonia) kilimensis in Central Africa
Summary A pair of Bronze SunbirdsNectarinia kilimensis was observed nest building over a period of 21 hours in the breeding season. Fig. 2 gives information on building activity. Of 144 arrivals with nest material 140 were concentrated in 8 hours from 08.00 to 16.00 hrs. Nest material consisted almost exclusively of grasses, plants, down and spider's webs; this material was, from the outset, used in an alternating pattern. The alone did the building. Nest-building methods are described, also various courtship activities of the . Nest building took 4 1/2 days, in the case of a second nest, 3 1/2 days.The 's bill and crown were visible when she was incubating. One young that had left the nest was fed by the alone. At least 17 days after this young one had fledged, it was chased aggressively by the , 6 days later also by the ; despite this, the same young bird was still in the territory more than three weeks after it had fledged.
  相似文献   

4.
Zusammenfassung Gemeinsame Verhaltensmerkmale ganzer Gruppen wurden bis jetzt nur selten zusammengestellt. Die Notwendigkeit einer derartigen zusätzlichen Kennzeichnung für die meisenartigen Vügel ergibt sich aus der Vielfalt der Auffassungen. Vor allem die Stellung der GattungenAegithalos undTichodroma ist unklar und in den wissenschaftlichen Werken uneinheitlich.Es wurde deshalb versucht, die wichtigsten Verhaltensweisen der GattungenParus undAegithalos einerseits darzustellen, andererseits die der GattungSitta gegenüberTichodroma undCerthia. Parus Alle bisher bekannten Arten dieser Gattung zerkleinern Nahrung, indem sie diese mit dem Fuß festhalten und Teile davon abzupfen bzw. die Schale von Samen zertrümmern. Dieses Verfahren beherrschen schon Jungvögel, die noch nicht selbständig Nahrung aufnehmen. Alle Meisen sind Höhlenbrüter; die Methode, Höhlen der verschiedensten Größen mit Moos weitgehend auszufüllen, wird als Anpassung an die Verschiedenartigkeit vorgefundener, meist durch Fäulnis entstandener Baumhöhlen gedeutet. Das Bedecken des unvollständigen Geleges kann Nestfeinde daran hindern, das Gelege beim Einblick in die Baumhöhle zu erkennen, da Meisenhöhlen im allgemeinen infolge der Unförmigkeit des Höhleneinganges nicht völlig dunkel sind. Die Nestlingszeit von rund 20 Tagen stellt wohl sicher eine Anpassung an das Brüten in einer geschützten Höhle dar. Ausführlich wird die Drohkombination besprochen, die bei allen Meisen festzustellen ist, die im Nest gestört werden. Diese Kombination, bestehend aus einem Zischlaut, dem Zuklappen des aufgesperrten Schnabels und gleichzeitigen Schlagen der Flügel an die Höhlenwände, kommt nur in einer Höhle zur vollen Wirkung und ist ein Zeichen dafür, daß Meisen phylogenetisch sehr alte Höhlenbrüter sind. Befiederte Jungmeisen wenden sie ebenso an wie in einer Höhle bedrängte Meisen- . Bei der Balz unterscheiden sich Meisen nicht grundlegend von anderen Passeres. Zum Sammeln von Vorräten sind nicht alle Arten von Meisen befähigt, sondern hauptsächlich solche, die im Winterhalbjahr vorwiegend von Samen leben. Kohl- und Blaumeisen sind möglicherweise nicht von Anbeginn Samenfresser gewesen; sie sammeln keine Vorräte. BeiParus major öffnet eine indische Rasse im Käfig keine Samen.Aegithalos Schwanzmeisen unterscheiden sich von denParus-Arten durch eine starke soziale Bindung an Artgenossen. Außer der Brutzeit trifft man nie einzelne Schwanzmeisen an, während Meisen auch mit anderen Arten vorlieb nehmen. Schwanzmeisen nächtigen stets in gegenseitiger Berührung und die Jungen rufen sich mit einem spezifischen Laut immer wieder zusammen. Schwanzmeisen sind nicht territorial. Mindestens beiAegithalos sowie bei dem amerikanischenPsaltriparus können mehr als zwei Altvögel am Nestbau und der Jungenaufzucht beteiligt sein. Von den Lautäußerungen der Schwanzmeisen hat nur einer eine gewisse Ähnlichkeit mit Meisenrufen, alle anderen sind stark verschieden; dies gilt auch für den Warnruf gegenüber Luftfeinden. Die Nestlingszeit der Schwanzmeisen entspricht der von Freibrütern; sie ist deutlich kürzer als bei Meisen. Am Nestbau beteiligen sich und , während bei denParus-Arten nur das baut.Sitta Während die Fähigkeit, abwärts zu klettern, nicht für alleSitta-Arten gilt, zerkleinern alle bisher bekannten Arten Nahrung, indem sie diese in Spalten stecken und mit dem Kopf nach unten hängend daraufklopfen. Dies ist ein grund-legender Unterschied zu allenParus-Arten. Alle holarktischenSitta-Arten sammeln Vorräte, alle sind Höhlenbrüter, die große Bruthöhlen, ähnlich wie die Meisen, verkleinern. Im Unterschied zu den Meisen fehltSitta ein Drohverhalten bei Störung im Nest. Eine Reihe von Arten schützt jedoch den Nesteingang teils durch eine Mauer aus Lehm, teils durch Beschmieren mit frischem Harz oder dadurch, daß Insekten am Flugloch so verrieben werden, daß ein Insektenduft entsteht. Bei Felsenkleibern sind diese Methoden kombiniert.Tichodroma Neuerdings wird der Mauerläufer eher zu den Kleibern gestellt als zuCerthia. Tatsächlich erinnert nur die Schnabelform an letztere Gattung. Es scheint, daß der Mauerläufer für seine Brut die Nähe von Felsschluchten oder Sturzbächen bevorzugt. Dort waren die Rufe flügger Junger im Nest nicht zu hören. Das auffallende Farbmuster kann eine ökologische Anpassung sein. Bettelnde Jungvögel schlagen die Flügel nach dem Ausfliegen viel höher und auffallender als andere Passeres. In der Lebensweise gleichtTichodroma vielfach dem FelsenkleiberS. neumayer, indem sie zur Brutzeit mehr Geröllfelder und den Rand von Schluchten aufsucht als Steilwände. Höhenunterschiede werden stets mit den Flügeln überwunden. Die auffallende Größe der Flügel läßt sich aus der Funktion leicht erklären. Das periodische Flügelzucken entspricht weitgehend dem vonSitta neumayer, nur mit dem Unterschied, daß es dafür beim Mauerläufer keiner erkennbaren Erregung bedarf. An der Bruthöhle wurde ein einziges Mal eine Pendelbewegung beobachtet, wie sie nur bei Kleibern vorkommt. Die Länge von Brutdauer und Nestlingszeit entspricht vor allem der der Kleiber.Certhia Der Stützschwanz ermöglichtCerthia eine völlig andersartige Klettermethode gegenüberSitta undTichodroma. Baumläufer sind an das Brüten in schmalen Spalten angepaßt. Die Brutdauer liegt zwischen der der Meisen und der Kleiber. Die Jungen sind sehr empfindlich und verlassen das Nest, bevor sie fliegen können, bei der geringsten Störung. Damit weichen sie ebenso von anderen Höhlenbrütern ab wie die brütenden , die gleichfalls sofort das Nest verlassen, wenn sie eine Gefahr wahrnehmen. Wenn das dem den zukünftigen Brutplatz demonstriert, schlüpft es ein und führt nach dem Herauskommen eine ritualisierte Schüttelbewegung aus, die Meisen und Kleibern fehlt. Auch die Schlafgewohnheiten sind verschieden.Es wird vorgeschlagen, die Schwanzmeisen als eigene Familie von den Meisen zu trennen. Den Kleibern gebührt ein eigener Familien-Status. Der Mauerläufer ist keinesfalls mitCerthia nahe verwandt, sondern sollte den Kleibern als Unter-familie zugeteilt werden, sofern er nicht eine eigene Familie darstellt.
Summary Up to the present time general behavioral characteristics of entire groups have rarely been synthesized. The necessity of an additional characterization of this kind for the tit-like birds is revealed in the multiplicity of taxonomic interpretations. The positions of the generaAegithalos andTichodroma are especially unclear and are diversely treated in scientific writings.Therefore it was attempted, on the one hand, to present the most important behavior patterns of the generaParus andAegithalos, and on the other hand, those of the genusSitta contrasted withTichodroma andCerthia. Parus All species of this genus known to date break up food items by holding them with the foot and picking off pieces or breaking off the hulls of seeds. Even young which do not yet feed independently have this behavior. All tits are hole nesters. The procedure of the extensive filling in of cavities of the most varied sizes with moss is explained as an adaptation to the variation in tree cavities encountered, largely as the result of rotting. The covering of an incomplete clutch can prevent predators' recognition of the clutch when looking in the hole, for tit holes are generally not completely dark as a result of the irregularity of the entrance. The nestling period of about twenty days certainly represents an adaptation to nesting in a protected cavity. The threat combination present in all tits when disturbed in the nest is discussed in detail. This combination, consisting of a hissing sound, snapping closed of the open bill and concomitant blows of the wings against the sides of the cavity, is fully elicited only in a cavity, and is an indication that hole nesting appeared quite early in the phylogeny of tits. Feathered young utilize this behavior just as do male tits which are disturbed in a cavity. Tits do not differ basically from other passerines in courtship. Not all species of tits store food; those which do are mainly those which feed predominantly on seeds during the winter. Coal and Blue Tits were perhaps not originally seed eaters; they do not store food. The Indian race ofParus major does not eat seeds in captivity.Aegithalos Long-tailed Tits differ fromParus species in their strong social ties to conspecifics. Lone Long-tailed Tits are never encountered outside of the breeding season, whereas other tits even show a preference for other species. Long-tailed Tits always spend the night in mutual contact and the young are brought together repeatedly with a specific call. They are not territorial. At least inAegithalos and the AmericanPsaltriparus more than two adults can take part in nest building and rearing of the young. Only one of the vocalizations of the Long-tailed Tit has a certain similarity to the calls of other tits; all the others differ markedly, also the warning call against aerial predators. The nesting period of the Long-tailed Tit corresponds to that of open nesters; it is clearly shorter than that of other tits. Both male and female participate in nest building, whereas in theParus species only the female builds.Sitta Whereas the ability to climb downwards does not hold for allSitta species, all species known to date break up food items by putting them in crevices and hammering on them with the head hanging downward. This is a basic difference from allParus species. All Holarctic species ofSitta store food and all are hole nesters which, like the tits, reduce the size of large nesting holes. As opposed to the tits,Sitta lacks a threat display when disturbed in the nest. However, a number of species protect the nest entrance, in part by a mud wall, and partly by smearing fresh resin about, or by rubbing insects around the hole so that an insect odor results. Rock Nuthatches combine these methods.Tichodroma The Wall Creeper has recently been placed closer to the nuthatches than toCerthia. Actually only the form of the bill resembles this genus. It seems that the Wall Creeper prefers the vicinity of rocky ravines or waterfalls for breeding. The calls of fledged young in the nest were not heard. The striking color pattern can be an ecological adaptation. After leaving the nest, begging young beat their wings much more widely and conspicuously than other passerines.Tichodroma bears a strong resemblance to the Rock Nuthatch,S. neumayer, in its way of life, in that for the breeding season it seeks out more boulderstrewn fields and ravine edges than steep cliffs. Vertical movements are always accomplished by flight. The striking size of the wing can be easily explained from its function. The periodic wing flashing corresponds closely to that ofSitta neumayer, and differs in the Wall Creeper only in the fact that no recognizable stimulus is needed for it to occur. A single observation was made of an oscillating movement at the nesting cavity, which only occurs in nuthatches. The length of the incubation and nestling periods corresponds especially well to that of the nuthatches.Certhia The prop-like tail makes possible a completely different method of climbing in contrast toSitta andTichodroma. Tree Creepers are adapted for breeding in narrow crevices. The length of the incubation period is intermediate between that of the tits and that of the nuthatches. The young are easily disturbed and will leave the nest, before they can fly, at the least disturbance. They also differ from other hole nesters in that the female will leave the nest immediately if she perceives danger. When the male shows the female the prospective nesting site he slips in and, after coming out, performs a ritualized shaking movement which is not found in tits and nuthatches. The sleeping habits also differ.It is suggested that the Long-tailed Tits and Bush Tits be separated from the other tits, and placed in a family by themselves. The nuthatches deserve familial status. The Wall Creeper is by no means closely related toCerthia, and ought to be designated a subfamily of the nuthatches, in so much as it does not represent a separate family.


Prof. Dr. Konrad Lorenz zum 60. Geburtstag gewidmet

Da uns nun nach Nestbau, Jugendbedaunung, Sperrachen, Stimme, Bewegungsweise z. B. Baum- und Mauerläufer oder Schwanz- und Waldmeisen untereinander durchaus nicht näher zu stehen scheinen als z. B. Waldmeisen und Kleiber, so begnügen wir uns mit den GattungenO. und M. Heinroth  相似文献   

5.
The problems of delimitation of species of Prosopis originate from the few morphological discontinuities which exist among some of them; some, however, originated as a result of wide distribution of germplasm without proper knowledge of the species, in particular, much material catalogued as P. juliflora, but being of other species, was distributed for reforestation projects worldwide. This work tests the morphological results obtained for P. pallida and P. limensis of the Peruvian–Ecuadorian coast and for P. juliflora of the Caribbean Basin of Colombia and Venezuela utilizing a study of AFLPs and a study of the morphology of plantlets developed in a conventional garden study. The phenogram obtained for the AFLPs demonstrates each of the three species to be a well differentiated cluster and the molecular variance between them is significantly greater than the variance within each species. Study of the plantlets also indicates statistically significant differences for four morphological characters between P. juliflora and the other two species (P. pallida and P. limensis). These results, in addition to the morphological differentiation evident between adult plants of P. pallida and P. limensis and the clear separation of these two species from P. juliflora, corroborate the genetic identity of the three taxa analyzed.  相似文献   

6.
The status of two poorly known fiddler crabs, Uca iranica Pretzmann, 1971, from the Persian Gulf, and U. albimana (Kossmann, 1877), from the Red Sea, was studied using two mitochondrial genes: the large subunit (16S) ribosomal (r)RNA and cytochrome oxidase subunit I (COI). A molecular phylogeny shows both U. iranica and U. albimana to be members of a monophyletic U. lactea species-complex containing six taxa, with three highly supported internal clades. Uca iranica and U. albimana are the closest genetically, but are different enough to be considered valid species (16S rRNA nucleotide divergence > 7.0%, and COI > 11.9%), and form a highly supported “western” clade with U. annulipes (in line with the original morphological concept). A West Pacific “eastern” clade includes U. lactea in the north and the more widely ranging U. perplexa. An Australian endemic species, U. mjoebergi, forms a third monotypic clade.  相似文献   

7.
Genetic transformation of androgenic-derived amphidiploid Festulolium plants (Lolium perenne L. × Festuca pratensis Huds., 2n = 4x = 28) by Agrobacterium tumefaciens has been achieved. Anther culture-induced calli of Festulolium “Bx351” were inoculated with Agrobacterium tumefaciens strain LBA4404 carrying pIG121-Hm encoding the hygromycin resistance (hph) and β-glucuronidase (uidA) genes under the control of a CaMV 35S promoter. Twenty-three putative transformants were obtained from the hygromycin selection, 19 of which (82.6%) showed GUS activity. The integration of transgene was detected by using genomic DNA PCR analysis, RT-PCR analysis and Southern blot hybridization, respectively, which revealed that foreign gene was integrated into the genomes of dihaploid transformants (2n = 2x = 14). The haploid embryogenic system offers a stable means of transformation, as the introduced trait can be readily fixed through chromosome doubling. An erratum to this article can be found at  相似文献   

8.
Parasitoid complexes of two species of the genus Phyllonorycter (Ph. apparella and Ph. populifoliella) reared from 2 plants (Populus tremula and P. nigra) were studied in Ul’yanovsk Province, Russia. Twenty species of parasitoids are new for Ph. apparella and 12 are new for Ph. populifoliella. Minotetrastichus frontalis and Pnigalio agraules are the dominant species for both parasitoid complexes. The highest relative abundance was observed for Ph. apparella on Populus tremula (75%) and for Ph. populifoliella on P. nigra (61%). The parasitoid complexes of Ph. apparella and Ph. populifoliella show high similarity (the Jaccard coefficient is 0.65).  相似文献   

9.
方宗杰 《古生物学报》2022,61(4):662-663
1993年, 于菁珊和董国义为辽宁上三叠统的非海相双壳类化石建立了一个新属辽宁蚌Liaoningia Yu and Dong, 1993, 以Liaoningia opima Yu and Dong, 1993作为模式种。然而, 早在1979年, 邢裕盛和刘桂芝就已为辽宁晚前寒武纪南关岭组所产的化石标本创建了新属名辽宁水母属Liaoningia Xing and Liu, 1979, 模式种是Liaoningia fuxianensis Xing and Liu, 1979。然而, 多数学者反对将它视为水母类化石, 有人怀疑辽宁水母属是假化石, 迄今学术界并无统一意见, 故本文暂将它归为疑问化石(Problematica)。根据“国际动物命名法规”, 我们提出一个新的属名Liaoningoconcha nom. nov., 用以替代Liaoningia Xing and Liu, 1979的次同义名Liaoningia Yu and Dong, 1993, 仍使用于菁珊和董国义在1993年指定的模式种, 中文译名不变。  相似文献   

10.
A dendroarchaeological survey of a traditional Nuu-chah-nulth plank house at Kiix?in, the former capital of the Huu-ay-aht First Nations, on the west coast of Vancouver Island British Columbia, was undertaken in the summer of 2002. Standardized dendroarchaeological techniques were employed to collect and analyse increment core samples collected from the house known as Quaksweaqwul. Floating ring-width series were compared to a locally prepared Western redcedar (Thuja heterophylla) master tree-ring chronology (1511–2002 AD) to determine when the trees used to construct the house were felled. The findings of the survey indicate that Quaksweaqwul was built after the 1835 AD growth year. As the amount of perimeter wood loss due to weathering and preparation is difficult to ascertain, no precise felling or construction date can be presented.

The results of this survey provide insights into Huu-ay-aht First Nations history and offer direct evidence for the general state of preservation of individual house posts and beams at Kiix?in. Additionally, the successful dating of a traditional First Nations village using a dendroarchaeological approach highlights the potential this technique may hold for developing similar insights at other sites along Canada's Pacific Coast.  相似文献   


11.
天然免疫系统是多细胞生物抵抗各种入侵微生物的第一道防线.Notch途径介导相邻细胞之间的相互作用,调节细胞、组织、器官的分化和发育.为了进一步探索Notch信号途径在果蝇天然免疫中的功能,利用Notch途径下游基因Su(H)和E(spl)的低表达突变体果蝇,通过体外注射病原体分析了生存率、血细胞的噬菌功能和抗菌肽的表达量以及突变体的血细胞数量.结果表明,革兰氏阴性细菌和真菌感染后果蝇E(spl)突变体的生存率、噬菌能力及抗菌肽的表达量明显降低,而且幼虫期血细胞出现异常增殖;Su(H)突变体只对真菌表现出敏感性,抗菌肽的表达量降低,但是对真菌的噬菌能力正常.此结果表明,Notch途径不仅影响个体的生长发育,而且在果蝇天然免疫中也起重要的调节作用.  相似文献   

12.
Acanthocephalus amini n. sp. (Palaeacanthocephala: Echinorhynchidae) is described from the intestine of Cichlasoma urophthalmus (Günther) (Pisces: Cichlidae) collected in the Río Champotón, a river in Campeche State, Mexico. It is the fourth species of Acanthocephalus Koelreuther, 1771 described from North American freshwater fishes, although two other species are known from South America. The new species is distinguished from other members of Acanthocephalus by features of its trunk, which is small, clavate, slightly expanded medially and bluntly pointed posteriorly. It is further distinguished by having a cylindrical proboscis armed with 13–14 longitudinal rows of 11–12 stout hooks; the apical and medial proboscis hooks are almost uniform in size and shape, decreasing in size towards the base; the posteriormost hooks are smaller, straighter and more slender than the anterior and middle hooks; and the lateral rows of hooks are more widely spaced, forming a conspicuous longitudinal area devoid of hooks. Furthermore, the lemnisci are saccate and shorter than the proboscis receptacle; and the neck is very short with a thick collar of trunk tegument, which encircles the base of proboscis. In males, the testes are in the middle third of trunk, diagonal, spherical and small relative to the body size, and there are six clavate cement glands. In females, the uterus forms a conspicuous, elongate, cylindrical egg reservoir. The new species is most similar to Aalabamensis Amin & Williams, 1983, but can be distinguished by its swollen, clavate trunk, the largest proboscis hooks being present apically and medially, smaller testes, a shorter male reproductive system relative to body size and females with a prominent uterus. They have different hosts and geographical distribution. The new species can be differentiated from Brasacanthus sphoeroides Thatcher, 2001, a similar species in a monotypic echinorhynchid genus, because the latter is larger, has smaller proboscis hooks and its lemnisci are longer than the receptacle.  相似文献   

13.
滇西二叠纪Shanita-Hemigordius(Hemigordiopsis)有孔虫动物群   总被引:3,自引:1,他引:3  
近几年来,在亚洲一些地区二叠系,发现了一个大型有孔虫Shanita,常与Hemigordius(Hemigordiopsis)伴生,组成特提斯海区二叠纪颇具特色的动物群,分布在一定的区域范围,形成了特定的生物地理区。本文主要记述这一动物群在我国滇西地区的发现及其纵横分布情况。本文材料系云南省地质局第一区测队、云南省地质研究所等单位送来我所鉴定的,薄片、照相、绘图均由我所技术室承担,特此致谢。滇西潞西、腾冲、镇康一带二叠系较发育,由巨厚的白云质灰岩、灰岩及泥岩等组成,含有和中国南部其它地区(秦岭地区除外)不尽相同的有孔虫动物群。据云南省地质局第一区域地质测量大队工作结果,此区二叠系自上而下,大致分层如下: 上覆地层:中三叠统或侏罗系  相似文献   

14.
(R)-2-Aryl-2-tropinone (9) was synthesized from (R)-2-carbomethoxy-3-tropinone (5) and was used as the key intermediate for the synthesis of (R)-2β,3β- and (R)-2α,3α-diaryltropanes. Inhibition of radioligand binding studies at the dopamine, serotonin, and norepinephrine transporters showed that the (R)-3β-(4-methylphenyl)-2β-phenyltropane (3b, RTI-422) possessed an IC50 value of 1.96 nM at the dopamine transporter and was highly selective for this transporter relative to the serotonin and norepinephrine transporters.  相似文献   

15.
A putative aminotransferase gene, kanB, lies in the biosynthetic gene cluster of Streptomyces kanamyceticus ATCC 12853 and has 66% identity with neo6 in neomycin biosynthesis. Streptomyces fradiaeneo6::tsr was generated by disrupting neo6 in the neomycin producer Streptomyces fradiae. Neomycin production was completely abolished in the disruptant mutant but was restored through self-complementation of neo6. S. fradiae HN4 was generated through complementation with kanB in Streptomyces fradiaeneo6::tsr. Based on metabolite analysis by ESI/MS and LC/MS, neomycin production was restored in Streptomyces fradiae HN4. Thus, like neo6, kanB also functions as a 2-deoxy-scyllo-inosose aminotransferase that has dual functions in the formation of 2-deoxy-scyllo-inosose (DOS). Electronic supplementary material  The online version of this article (doi:) contains supplementary material, which is available to authorized users.  相似文献   

16.
Chromosome mapping of three common markers, ie major and 5S rRNA genes (rDNA) and telomeric repeats, and conventional chromosome bandings were applied to two sibling species, Apodemus sylvaticus Linnaeus, 1758 and A. flavicollis Melchior, 1834, to further investigate intra- and interspecific karyological differentiation in the genus Apodemus. A slight variation of the rDNA-patterns was detected between the two Apodemus species. In both of them, the major NORs were located on autosome pairs 8, 11, 12 and 22, while the two other rDNA sites detected on chromosomes 7 and 21 were variable in, respectively, A. sylvaticus and A. flavicollis. Several tiny rDNA sites were present on the sex chromosomes in both species, but their incidence was lower in A. flavicollis. Single 5S rDNA chromosomal sites were conserved on chromosome pair 20. No interstitial sites of telomeric repeats were present in either species. In the Sicilian population of A. sylvaticus, the constitutive heterochromatin pattern corresponded to the “sylvaticus-E1” cytotype, while A. flavicollis had a species-specific pattern restricted to centromeres of all chromosomes. The results are discussed in relation to cytogenetic data available for the genus, with emphasis on the Sylvaemus group/subgenus.  相似文献   

17.
The effects of β-lactam antibiotics (penicillin, carbenicillin and cefotaxime), cytokinins, and auxins including phenylacetic acid, a β-lactam breakdown product, were evaluated during in vitro shoot morphogenesis in two hybrid aspens; P. tremuloides × P. tremula (XTTa) and P. x canescens × P. grandidentata (XCaG). Although different callus and shoot induction media were used for both hybrids, the β-lactams often engendered similar responses. At concentrations of 1,000 mg l−1, carbenicillin adversely impacted shoot elongation and, to a lesser degree, shoot regeneration. Cefotaxime enhanced caulogenesis for all of the concentrations evaluated (125–500 mg l−1) especially when the cytokinin thidiazuron was used for shoot induction. The shoots formed faster and in greater numbers; and the improvements were significant (α = 0.05) for both hybrids. However, hyperhydricity was more problematic when cefotaxime was included in the media. The incidence of shoot hyperhydricity for the XCaG hybrid was more than twice as great for the highest cefotaxime concentration evaluated (500 mg l−1) than for the control (>90% vs. ~40%). Penicillin had an opposite effect. Hyperhydricity frequencies for the XCaG hybrid were lower when the media were supplemented with penicllin and the reductions were statistically significant at concentrations of 500–1,000 mg l−1. The effects of the antibiotics were generally not reproduced by the auxins (0.1–100 μM), including phenylacetic acid, or the other potential β-lactam degradation products evaluated (e.g. phenylmalonic acid, aminopenicillanic acid). The antibiotics may have affected shoot hyperhydicity indirectly via changes in the time course of shoot regeneration.  相似文献   

18.
Summary Young birds of both species return almost exclusively to their natal colony for breeding and breeders are higly faithful to both partner and territory in subsequent years. There is no or very limited emigration to other colonies which are 2–5 km distant. The consequences of the genetic isolation are discussed: In both species the tendency to form subspecies can be detected. High mortality rates are interpreted as a mean to eliminate any degenerated bird which could result from the close interbreeding in these small and isolated populations.  相似文献   

19.
Zusammenfassung Im Harz besiedelten 1969–1983 Trauerschnäpper und Wasseramsel Südhänge bevorzugt und erfolgreicher als Nordhänge, Tannenmeisen dagegen Nordhänge. Siedlungsdichte, Höchstvorkommen, Gelegegröße, Zahl der flüggen Jungen pro erfolgreiches Paar, relativer Bruterfolg und Jungenproduktion (bei der Wasseramsel auch die Zahl der Zweitbruten) sind an den Süd-(Nord-) hängen größer als an den Nord-(Süd-)hängen, Legebeginn/Schlüpftermin liegen früher (Abb. 8). Zwar sind bei der Kohlmeise Gelegegröße, Zahl der flüggen Jungen pro erfolgreiches Paar und relativer Bruterfolg an den Nordhängen größer als an den Südhängen, doch die übrigen brutbiologischen Daten zeigen, daß auch für sie Südhänge nahrungsökologisch günstiger sind. Trauerschnäpper, Kohl- und Tannenmeise besiedelten bevorzugt (ca. 90 %) Hänge mit der gleichen Exposition, an der die Vögel geboren worden waren. Die unterschiedliche Bedeutung der südlichen bzw. nördlichen Hangexpositionen für die 4 Arten kann am deutlichsten aus der Zahl der flüggen Jungen pro ha oder pro km Flußlänge abgelesen werden (Abb. 8): Sie übersteigt an den Südhängen die an den Nordhängen beim Trauerschnäpper um 1000 (–2000) %, bei Wasseramsel und Kohlmeise um 65–90 %; umgekehrt ist sie bei der Tannenmeise an den Nordhängen um 100–130 % größer. Die Nahrungssituation wird als entscheidend für die Ergebnisse angesehen.
Exposure and breeding biology ofCinclus cinclus, Ficedula hypoleuca, Parus major andP. ater
Summary From 1969 to 1983 breeding biology and settling behaviour were investigated in the Harz mountains.Ficedula hypoleuca andCinclus cinclus preferred south exposed slopes to north exposed slopes and were more successful on southern slopes. On the other handParus ater preferred northern slopes. ForFicedula hypoleuca andCinclus cinclus population density, altitudinal limit, clutch size, number of fledged young per successful pair, relative breeding success and number of fledged young per ha or per km of river bank were higher on southern than on northern slopes. The opposite was true forParus ater for northern slopes versus southern slopes (Fig. 8). InParus major clutch size, number of fledged young per successful pair and relative breeding success were also higher on northern slopes than on southern slopes. Data of breeding biology show, however, that the food ecology of south exposed slopes forParus major is also more favourable than that of north exposed slopes. For nestingFicedula hypoleuca, Parus major andP. ater prefer (to almost 90 %) the type of slope at which they had been born. The importance of north or south exposure is best shown by the number of fledged young per ha or per km of river bank (Fig. 8): On south exposed slopes it exceeds that on north exposed slopes by about 1000 (to 2000) % forFidecula hypoleuca, and by about 65–90 % forCinclus cinclus and forParus major. On the north exposed slopes, however, the number of fledged young per ha ofParus ater exceeds that of the south exposed slopes by about 100 to 130 %. The results are chiefly explained by the food situation.
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20.
Zusammenfassung Brandentenküken verfügen über drei verschiedene Taucharten, die sich nach Ausführung und Tauchdauer deutlich unterscheiden lassen. Während das Nahrungstauchen in der 6. Lebenswoche eingestellt wird, bleiben Tauchbaden und Fluchttauchen lebenslang erhalten. Neben dem Nahrungstauchen werden weitere Techniken des Nahrungserwerbs in Abhängigkeit vom Nahrungsangebot und dem Entwicklungsstand unterschiedlich häufig angewendet. Der zeitliche Aufwand für die Nahrungsaufnahme ist in den ersten 2 Lebenswochen maximal. Anschließend nimmt er, bei schneller als bei kontinuierlich ab. Kälteperioden führen zu einer weiteren Reduzierung. Die Schlafhäufigkeit sinkt nach einer anfänglichen Zunahme (bis 10. Lebenswoche) ab. Kälteperioden bewirken eine Zunahme. Unter 3 verschiedenen Schlafhaltungen wird bis zur 12. Lebenswoche das Schlafen im Liegen bevorzugt. Danach nimmt es zugunsten des einbeinigen Schlafens im Stehen, das erstmals in der 7. Lebenswoche auftritt, ab. Kälteperioden stellen die ursprünglichen Häufigkeitsverhältnisse zwischen beiden Schlafhaltungen wieder her. Brandentenküken bilden in den ersten Lebenswochen Schlafhaufen. Ihre Häufigkeit sinkt bis zur 12. Lebenswoche kontinuierlich auf Null ab.
Ontogenetic changes in sleeping, diving and foraging behaviour in Shelduck (Tadorna tadorna) ducklings
Summary Shelduck ducklings show different types of diving behaviour: diving for food, flight-diving and dashing and diving in comfort situations. These types differ by diving duration and the behaviour of the ducks. In diving for food diving duration and frequency decrease during the first 6 weeks. After this, no food diving was observed. Other feeding methods include sieving, upending, pecking on the surface of water, feeding on plants and foot-trampling. Except for feeding on plants, which was first observed in the 10th week, all feeding methods are present in one day old ducklings. The share of foraging time is highest during the first 2 weeks of life. Afterwards it decreases (in females faster than in males) from about 50 to 20 %. During cold weather, it was still lower whereas resting and sleeping behaviour increased. After an increase during the first 10 weeks of life, the share of resting decreases to 25–40 % of observation time. Shelduck ducklings have 3 different sleeping postures: lying, standing on one leg, standing on two legs. During the first weeks of life ducklings only sleep standing on two legs or lying on the ground, the latter is being clearly preferred. Standing on one leg appeared in the 7th week. Its frequency increased and it became the most prominent resting pattern. Only during cold spells shelducks do return to sleep by lying on the ground. Under such conditions also sleeping in contact with one another reoccurs, which is typical for ducklings during their first weeks of life.
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