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1.
《Ibis》1930,72(S1):503-518
Although so well known in South Africa, where the species was discovered more than a hundred years ago. and mainly because in that part of the continent the bird's tail is of plain, not spotted fan pattern, fulvicapilla has a stormy generic history, only reaching Cistieola finally through Sylvia, Drymoica, Camaroptera, Calamodyta and Dryodromas.  相似文献   

2.
《Ibis》1930,72(S1):156-172
This third species of Cloud-scraper was first named by Dr. von Heuglin in 1862 from an adult male in Summer dress obtained by himself in Abyssinia. Later (in 1869), not realizing their specific identity, von Heuglin gave examples of the same species in Winter and juvenile dresses with different specific names, viz. iodopyga and habessinica , but did not have to contend with the difficulty of separating ayresii from brunnescens because the former species does not occur in Abyssinia. Elsewhere, from Kenya Colony to South Africa, that has always been the difficulty, and wherever the two species were subsequently found they were more or less indiscriminately related to one another as forms or allies of ayresii (under that bird's wrong name terrestris) , until, in 1913 *, Roberts showed the differences between them in South Africa, and, in 1922†, van Someren the same for Kenya Colony.  相似文献   

3.
《Ibis》1930,72(S1):67-69
A n assemblage of forty species perhaps more nearly akin to those of the genera Apalis, Prinia, Incana, and Franklinia than any other; of size and proportions varying from about those of the tiny Phylloscopus proregulus to those of the large Sylvia nisoria , but with proportionately blunter and shorter wings, bills and tails of great variety of length and shape, but the tail most often well graduated—coloration almost entirely composed of sober shades and tints of browns, greys, buffs, and reds, with or without black above, and whitish with more or less of colour-wash here and there below: very great variety of colour-pattern, the head-top often concolorous with, but as often in contrast with the back, frequently redder; and both, or either one or the other, plain or patterned with black in every degree of shade, profusion, and style: the lower side generally plain, rarely spotted, the tail of a decorative "spotted fan" pattern, except when sometimes modified so as to look plain—either all black or all light coloured.  相似文献   

4.
《Ibis》1930,72(S1):519-524
The least of all the Cisticolae—although some of the races of other species are as small—a tiny, roundabout little creature, scarcely bigger than a Goldcrest (Regulus) , and of not very different proportions: confined to a comparatively small part of East Africa. In life, quite "a Cisticola", but one with a good deal of individuality in its behaviour, with quick darting movements, and at home in fairly dry, tall "bush" country. Discovered only forty-five years ago, nana was classified without hesitation in its natural place among the Cisticolae, and there it has remained more or less undisturbed; although near relationship with Apalis angusticauda, a bird of very like coloration, but with a number of unlike characters of form, has been suggested.  相似文献   

5.
《Ibis》1930,72(S1):413-432
With what has already been said of the bird in the Definition of the pair and the Key to species, robusta requires little farther introduction. Some peculiarities in the bird's moults will require particular attention later on, when it comes to defining the racial variation.  相似文献   

6.
《Ibis》1930,72(S1):532-543
An easily recognized little bird in both of its very different seasonal dresses: one with no very near relative among the other species, but thoroughly Cirticoline from every point of view, alive or on the table: about the size of the Wood-Warbler (P. sibilatrix) , but with a shorter tail and much shorter wings, (totally different coloration), and in behaviour more like a bush-loving Sylvia , the Whitethroat (S. communis) for instance, only without any of that bird's aerial love-dances.  相似文献   

7.
《Ibis》1930,72(S1):525-531
Another of the more recently discovered North-east African species: not a very small bird, but about the size of the Whitethroat (Sylvia communis) and of not very different proportions, only the tail noticeably shorter: an inhabitant, for (he most part, of thorn-bush country, with manners, so far as they are known, more or less Sylvia-like.  相似文献   

8.
《Ibis》1930,72(S1):544-555
A smallish, rather slender-built bird; quite a typical Cisticola like subruficapilla , which species despite its different coloration is-one of if not the nearest of its allies, about the same size, build and proportions as the Sardinian Warbler (S. melanocephala) and with much moreover in its behaviour which recalls that and other quite differently coloured bush-loving Sylvia Warblers, such as, for instance, the Whitethroat (S. communis).  相似文献   

9.
10.
《Ibis》1930,72(S1):180-206
The only species of Cisticola not inhabiting Africa at all, but with headquarters in south-eastern Asia and Australia, and ranging thence no further to the westward than southern India: Latham's English name, "The Exile Warbler"*is therefore very appropriate.  相似文献   

11.
《Ibis》1930,72(S1):77-111
The only European and most familiar species * of the whole genus Cisticola , of which, according to ancient designation †, it is the representative type-species. It is also the species with the widest range.  相似文献   

12.
《Ibis》1930,72(S1):461-493
What has been said about it in the introduction to the group leaves little necessary to say here of brachyptera s systematic position, but the following historical note relating to the bird's confusion with rufa will probably be useful.  相似文献   

13.
《Ibis》1930,72(S1):432-457
This very well known large bird shares with galactotes the distinction of having greater seasonal difference of dress than any other of the thirty-eight African Cisticolae: Asiatic-Australian exilis lias even greater, but only in the cock bird.  相似文献   

14.
G- and C-banded karyotypes of the genus Oryx were compared using the standard karyotype of Bos taurus. Chromosomal complements were 2n = 56 in O. gazella gazella, 2n = 58 in O. g. beisa and O. g. callotis, 2n = 56-58 in O. dammah, and 2n = 57-58 in O. leucoryx. The number of autosomal arms in all karyotypes was 58. Nearly all variation in diploid number was the result of three independent centric fusions, but one 2n = 57 specimen of O. g. gazella deviated from the normal complement of 2n = 56 due to XXY aneuploidy. A 2;17 centric fusion was fixed in O. g. gazella, whereas O. g. beisa and O. g. callotis lacked this fusion and had indistinguishable karyotypes. Oryx dammah was polymorphic for a 2;15 centric fusion, and O. leucoryx was polymorphic for an 18;19 centric fusion. The five Oryx taxa shared a fixed 1;25 centric fusion; the small acrocentric element involved in the 1;25 fusion was identified by fluorescence in situ hybridization using a cosmid specific to Bos chromosome 25. The X and Y chromosomes were also conserved among the five taxa. Oryx g. gazella differed from the other Oryx species because of the fixed 2;17 centric fusion. This difference reflects an apparently longer period of geographic isolation between O. g. gazella and other populations of Oryx, and it is consistent with the classification of O. gazella and O. beisa as distinct species (see Kingdon, 1997). The lack of monobrachial relationships among the Oryx taxa indicates that sterility barriers between species have not developed. Viability of hybrid offspring constitutes a threat to captive breeding programs designed for endangered species conservation; in the case of Oryx, the 2;15, 2;17, and 18;19 metacentrics could serve as marker chromosomes for assessing hybridization between certain Oryx taxa.  相似文献   

15.
We compared the mating systems and genital morphology of three Orius species dominant in Japan: Orius sauteri (Poppius), Orius minutus (L.), and Orius strigicollis (Poppius) (Heteroptera: Anthocoridae). In all three species, the males were polygamous and could inseminate at least three females at a rate of one female per day. Compared to the other two species, the O. minutus males had a lower rate of success in three consecutive mating orders. The mated females laid the same number of eggs irrespective of mating sequence. Orius minutus and O. strigicollis females were found to be monandrous, and they re‐mated with another male only when the 1st mating failed. In contrast, O. sauteri females were polyandrous and accepted a 2nd male even when the 1st mating was successful. Multiple mating with a single male did not increase their fecundity, and it decreased the hatching success of eggs. Mating with multiple males did not affect the fecundity or hatching success. Our scanning electron microscopy observation suggested that the genitalia of O. minutus and O. strigicollis were more similar in shape. The similarities in mating system and morphology between O. minutus and O. strigicollis support a close phylogenetic relationship.  相似文献   

16.
A method was developed to differentiate between fourth-stage larvae (L4) of two species of porcine nodular worms, Oesophagostomum dentatum and O. quadrispinulatum, by computer-assisted analysis of digitised microphotographs of L4 grown in vitro for various time periods and of L4 ex vivo. The overall lengths of the larvae and the lengths of the oesophagus as well as parameters describing the shape of the oesophagus and buccal capsule were measured and a formula based on these parameters was developed that could differentiate between the two species on the basis of the morphometric data. It was demonstrated that morphometry can produce unbiased data which can be employed for the calculation of indices suitable for the differentiation of morphologically different specimens. Computer-based techniques facilitate the processing of the complex data and offer the option for automation of measurements for routine applications.  相似文献   

17.
Sea-level fluctuations during the Pliocene and Pleistocene have shaped the landscape of the Northland region of New Zealand. We examined the comparative phylogeography of three skink species (Oligosoma moco, O. smithi, O. suteri) in northeastern New Zealand in order to investigate the impact of the historical processes that have prevailed since the Pliocene on the Northland fauna. O. moco, O. smithi and O. suteri have similar distributions across northeastern New Zealand, frequently occurring in sympatry. We obtained sequence data from across the entire range of each species, targeting the ND2 mitochondrial gene. Using Neighbor-Joining, Maximum likelihood and Bayesian methods, our analysis revealed contrasting phylogeographic patterns in each species. We found substantial phylogeographic structure within O. moco, with three distinct clades identified. Similarly, deep phylogeographic divergence was evident within O. smithi, with three distinct clades present. Clade 1 included O. smithi populations from the Three Kings Islands and the western coastline of Northland, while Clade 2 encompassed the remainder of the range. However, since Clade 3 corresponded to a described species (O. microlepis), O. smithi might represent a species complex. In both O. moco and O. smithi, divergences among clades are estimated to have occurred in the Pliocene, with divergences within clades occurring during the Pleistocene. In contrast, genetic divergence among O. suteri populations was extremely limited and indicative of more recent divergences during the Pleistocene. The lack of phylogeographic structure in O. suteri might be a consequence of its oviparous reproductive mode, which restricted its distribution to warm northern refugia during glacial maxima. Differences in the ecology and biology of each species might have produced contrasting responses to the same historical processes, and ultimately diverse phylogeographic patterns. Our study reveals an absence of consistent and concordant phylogeographic patterns in the Northland biota, even within the same taxonomic group.  相似文献   

18.
Opuntia abjecta and O. militaris have been placed in synonymy under the Caribbean species O. triacantha for the past 30 years. Recent molecular phylogenetic evidence has shown, however, that O. abjecta and O. triacantha are actually in two very different clades suggesting that the Floridian endemic O. abjecta should be recognized as a distinct species. Here, we summarize major morphological differences between O. abjecta and O. triacantha. We also include new sequence data from the rare Cuban taxon, O. militaris, in a molecular phylogenetic analysis to determine its relationship to O. triacantha and O. abjecta. We discuss the putative hybrid taxa O. cubensis and O. ochrocentra, which currently are treated as synonyms. We also show through analysis of morphological and molecular characters that these two taxa were derived from two independent origins from divergent maternal progenitors, confirming that O. ochrocentra should not be treated as synonymous with O. cubensis. A key is provided for identifying these taxonomically confusing taxa and their close relatives. This study emphasizes the distinctions among O. abjecta, O. militaris, and O. triacantha and illustrates that extreme caution must be employed when using herbarium specimens for identifying species of Opuntia. It also indicates that broad phytogeographic assumptions regarding species’ relationships in Opuntia may sometimes be misleading. Hybridization and polyploidy are common in Opuntia and have played a role in the formation of new species in this group as well. A neotype is here designated for O. triacantha.  相似文献   

19.
Two species of Odontocheila, O. confusa and O. nodicornis, from the Neotropical Region were studied regarding their karyotypes, localisation and activity of ribosomal genes and C-banding. The species, although belonging to the same genus, have quite distinct karyotypes. O. confusa has 10 pairs of autosomes and a single sex chromosome mechanism of the XY/XX type, thus a diploid value of 2n = 22 in males and females. One aneuploid male with a diploid number of 2n = 20 and one male with three B chromosomes were found in a total of eight males studied. O. nodicornis has 17 autosomal pairs and also a single chromosome system but of the X0/XX type, thus a diploid value of 2n = 35 in males and 2n = 36 in females. Fluorescence in situ hybridisation (FISH) revealed the presence of rDNA clusters in two autosomes in both species in mitotic and meiotic figures. Silver staining of male interphase nuclei confirmed the FISH results and showed that all rDNA genes were active. C-banding analysis revealed the presence of constitutive heterochromatin in the centromeres of all chromosomes in the two species plus two pairs in O. nodicornis with terminal positive C-bands. These results are discussed from the cytogenetic and evolutionary point of view.  相似文献   

20.
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