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1.
Proposed new realignments in the angiosperms   总被引:1,自引:0,他引:1  
Our attempt at putatively phylogenetic classifications of Angiospermae, considering our vast ignorance of more than 120 million years of evolution of the class, must be very tentative and elastic to make full use of the new approaches and new data constantly being made available to us. Some of the realignments thus required in my system of classification are here explained. Among others, the Paeoniales are recognized and include Glaucidiaceae; various shifts of families are made within Thei–florae–Violiflorae–Malviflorae; Thymelaeaceae and Simmondsiaceae are transferred to Euphorbiales; Emblingiaceae, Gyrostemonaceae and Bataceae are added to Sapindineae; Fabineae, with Connaraceae, Surianaceae and Fabaceae, are transferred to Rutiflorae; Proteiflorae are placed near Rutiflorae, especially Fabineae; the largely Australasian–African Pittosporales are explained; Cornaceae are severely pruned; Haemodoraceae and Velloziaceae are transferred to Commelinales; Arecales, Cyclanthales and Pandanales are separated into unrelated superorders; and Typhiflorae are moved into closer proximity with Commeliniflorae.  相似文献   

2.
In the current study, two new coccidian species (Protozoa: Apicomplexa: Eimeriidae) obtained from short-crested flycatcher Myiarchus ferox (Gmelin) are reported from Brazil. Isospora feroxis n. sp. has o?cysts which are spheroidal to sub-spheroidal, 18.7 × 18.0 μm, with a smooth and bi-layered wall, c. 1.2 μm. The micropyle and o?cyst residuum are absent, but two polar granules are present. Its sporocysts are broadly ellipsoidal and 11.7 × 8.5 μm. Stieda and substieda bodies are present. A sporocyst residuum is present and the sporozoites have a refractile body and nucleus. O?cysts of Eimeria sicki n. sp. are spheroidal to sub-spheroidal, 30.3 × 28.5 μm, with a smooth and bi-layered wall, c. 1.3 μm. The micropyle, o?cyst residuum and polar granule are absent. Its sporocysts are ellipsoidal, 18.4 × 10.0 μm. Stieda and substieda bodies are present. A sporocyst residuum is present and sporozoites have a refractile body and nucleus.  相似文献   

3.
The genus Podothrips Hood is redefined, and three new species are described: orion and australis from Australia and moundi from New Guinea. Two new synonymies are recorded in Podothrips and fuscus Moulton and monsterae Moulton are excluded. A key to the nineteen species and an annotated catalogue are provided. The distribution and biology of the genus are briefly discussed.  相似文献   

4.
A contrast between temperate and tropical Cladocera, Copepoda and Rotifera zooplankton fauna shows a markedly different size composition and species diversity. There are fewer species, and these are generally smaller in the tropics than in either the North or South Temperate Zones. Larger species of the genera Daphnia and Simocephalus are relatively rare in the tropics, while members of Eurycerus and Saycia are absent. Members of the families Holopedidae, Leptodoridae and Polyphemidae increase in abundance toward the temperate regions. Two small cyclopoid copepods are common in tropical zooplankton, while many of the common larger species of other regions are absent or very rare. The chief rotifer components are Keratella tropica and species of Brachionus.  相似文献   

5.
The chromosome numbers of 10 previously uncounted species in Cheilanthes and 1 species of Notholaena are reported. Several confirmatory counts are also listed. One of the plants, Cheilanthes parryi, should probably be retained in the genus Notholaena. Four plants are sexual diploids, three are diploid apomicts, four are triploid apomicts, and three are tetraploids.  相似文献   

6.

The subfamily Deltocephalinae is represented in New Zealand by 3 tribes, 9 genera, and 20 species, of which 3 genera and 13 species are new to science. All taxa are described, and keys are given for their separation. Three of the genera are endemic, 3 are Australian, 2 are Holarctic, and 1 is cosmopolitan. Nesoclutha and Macrosteles are recorded in New Zealand for the first time, and the presence of Deltocephalus is authenticated. Fourteen species are endemic, 4 are Australian, 1 is widespread in the Pacific area, and 1 is Holarctic. Nesoclutha pallida, Macrosteles fieberi, and Deltocephalus hospes are recorded in New Zealand for the first time.  相似文献   

7.
Data are presented recording the presence of 49 species of bloodsucking cerato-pogonids in Trinidad, West Indies. Of these, 45 are Culicoides, one is a Leptoconops, and three belong to Forcipomyia (Lasiohelea). Five species are reported from Tobago: three Culicoides, one Leptoconops, and one Lasiohelea. The males of Culicoides benarrochi and C. fluviatilis are described for the first time, and the female of C. debilipalpis is redescribed. Culicoides filariferus and C. pseudodiabolicus are resurrected from synonymy, and characters are presented distinguishing them from C. diabolicus and C. guttatus. Biological data and keys to genera and species are included.  相似文献   

8.
Lu Liu  Bao-Zhen Hua 《Tissue & cell》2017,49(5):622-631
Bittacidae and Panorpidae are the two largest families in Mecoptera. The larvae of Bittacidae are different from those of Panorpidae in external morphology and habits, and have an interesting habit of spraying the body surface with soil through the anus. However, it remains unknown to date whether the larval midguts are different in structure between the two families. Here the ultrastructure of the larval midguts of the hangingfly Bittacus planus Cheng and the scorpionfly Neopanorpa longiprocessa Hua & Chou were compared using light, scanning, and transmission electron microscopy. The midguts of both species are simple tubes of single layered epithelia with digestive and regenerative cells but without diverticula. The basal plasma membrane of epithelial cells exhibits infolding in B. planus, but is closely apposed to its basal lamina in N. longiprocessa. Lymph spaces are present between adjacent epithelial cells in B. planus, but are absent in N. longiprocessa. The regenerative cells are scattered among the digestive cells in B. planus, but are aggregated in N. longiprocessa. The longitudinal muscle bands are compact in B. planus, but are sparse in N. longiprocessa. The compact longitudinal muscle bands are likely associated with their soil-spraying habit in Bittacidae.  相似文献   

9.
The number of chromosomes in cells of the root meristem of seedlings of wild and cultivated species of Cruciferae plants capable of hybridizing with rapeseed Brassica napus is studied. Only diploid metaphases are observed in seedlings of Brassica juncea, Diplotaxis tenuifolia, and Raphanus raphanistrum. In B. napus and B. cretica roughly 5% of the seedlings are mixoploid. Diploid cells are dominant in the mixoploids, though hypo-and hyperdiploids are also encountered. Nearly 20% of the seedlings of B. campestris and R. sativum are mixoploid, a significant fraction of which contains di-triploid chimeras. In B. nigra less than one-half of the seedlings are truly diploid, the majority of the plants being mixoploid. Seedlings containing preferentially tetraploid and triploid cells are dominant. The biological significance and possible causes of the newly discovered mixoploidy are discussed.  相似文献   

10.
《Genomics》2020,112(5):3803-3814
FT-INTERACTING PROTEIN (FTIP) gene family in rice are the members of multiple C2 domain and transmembrane region proteins (MCTPs). There are many homologs of OsFTIPs in plants; however, the bioinformatics of them remains unclear. In the studies, 13 OsFTIP genes are identified in rice. OsFTIPs are unevenly located in 12 chromosomes. The OsFTIPs are phylogenetically divided into three clades. Cis-elements respond to abiotic stress, light, and hormones are found in the promoter region of OsFTIPs which are induced by the stimuli. All OsFTIPs are expressed with different profiles. Syntenic analysis of 128 OsFTIPs and FTIP-like homologs reveals that various number of gene pairs are identified between rice and other species. The 128 FTIP-like homologs are divided into six groups which fall into three classes. Ten motifs are shared by most OsFTIPs and their homologs. The studies provide a theoretical basis for further elucidating the functions of OsFTIP gene family.  相似文献   

11.
12.
《Geobios》1986,19(3):335-356
After a short historical introduction, the principal notions used to study the connections between ontogeny and phylogeny are desribed. The three fondamental standards (shape, age, size) upon which are made ontogenetic comparisons are defined and discussed.The different ontogenetic heterochronies are described and illustrated with concrete paleontological examples. Successively are studied:u
  1. -dwarfirsm and giantism which are particularcases;
  2. -the 4 types of heterochrony which affect somatic development (neoteny and acceleration) or sexual maturation (hypermorphosis and progenesis);
  3. -the innovations which are a fast appearence of a new character and their associations with the 4 elementary heterochronies.
The heterochronies are connected with phylogeny. This leads to the definition of two fondamental tendancies: paedomorphosis and peramorphosis; the terms proterogenesis and palingenesis are redefined. To conclude, this study is inserted in a more wider context that shows the importance of ontogenetic knowledge to understand numerous evolutif processes (tempos in evolution, demographic strategies, cladism).  相似文献   

13.

Background  

The Bacteroidetes and Chlorobi species constitute two main groups of the Bacteria that are closely related in phylogenetic trees. The Bacteroidetes species are widely distributed and include many important periodontal pathogens. In contrast, all Chlorobi are anoxygenic obligate photoautotrophs. Very few (or no) biochemical or molecular characteristics are known that are distinctive characteristics of these bacteria, or are commonly shared by them.  相似文献   

14.
李玉  陈双林  李惠中 《菌物学报》1993,12(Z1):107-112
本文补报了中国团毛菌科四个种,弱小团网菌Arcyria exigua sp. nov.和聚生团网菌Arcyria aggregata sp. nov.为新种,瑞士团网菌Arcyria helvetica和纹丝半网菌Hemitrichia intorta为中国新记录种。文中对二新种进行了描述,附有形态特征电镜扫描照片,并讨论了与相似种间的区别。新种的模式标本保存在中国科学院微生物研究所真菌标本室。  相似文献   

15.
Why Don't Chimpanzees in Gabon Crack Nuts?   总被引:5,自引:0,他引:5  
Some populations of wild chimpanzees (Pan troglodytes) use hammers and anvils of stone or wood to crack open nuts for food. Others do not. The aim of this study was to ask why one non-nut-cracking population, in the Lopé Reserve, Gabon, lacks this useful form of tool use. We tested 10 hypotheses: (1) nuts are absent; (2) nuts are few; (3) nuts are unsuitable; (4) hammers are absent; (5) hammers are unsuitable; (6) anvils are absent; (7) anvils are unsuitable; (8) nuts are displaced by better food items; (9) intelligence is insufficient; and (10) knowledge is insufficient. All but the last are clearly falsified, leaving by exclusion the likelihood that Lopé's chimpanzees lack the technology—knowledge of appropriate technique—to exploit this resource. Thus, the behavioral differences across populations of these apes are cultural and not environmentally dictated. This explanation is congruent with the distribution of chimpanzee nut-cracking across Africa.  相似文献   

16.
Three new coccidian (Apicomplexa: Eimeriidae) species from the buffy-fronted seedeater Sporophila frontalis Verraux in Brazil are reported in the current study. Isospora frontalis n. sp. oöcysts are spherical to sub-spherical, 27.9 × 26.9 μm, with a smooth, bi-layered wall c.1.4 μm thick. A micropyle and an oöcyst residuum are absent, but polar granules are present. Sporocysts are elongate ellipsoidal, 19.6 × 11.1 μm. The Stieda body is knob-like and the substieda body is slight. The sporocyst residuum is composed of scattered granules, and the sporozoites are vermiform with a refractile body and a nucleus. Isospora teresopoliensis n. sp. oöcysts are spherical to sub-spherical, 25.7 × 24.3 μm, with a smooth, bi-layered wall 1.3 μm thick. A micropyle, oöcyst residuum and polar granule are absent. Sporocysts are ovoid, 18.8 × 11.2 μm. The Stieda body is nipple-shaped and the substieda body is large and prominent. The sporocyst residuum is composed of scattered granules, and the sporozoites are large and elongate, with a refractile body and nucleus. Oöcysts of Isospora chanchaoi n. sp. are spherical to sub-spherical or ovoid, 24.2 × 22.0 μm, with a smooth, bi-layered wall c.1.2 μm thick. Both a micropyle and an oöcyst residuum are absent, but one or two polar granules are present. The sporocysts are ellipsoidal, 16.1 × 10.3 μm. The Stieda body is nipple-shaped and the substieda body is small but prominent. The sporocyst residuum forms a compact mass of granules, and the sporozoites are large and elongate, with a refractile body and a nucleus.  相似文献   

17.
Several axes of the coenopterid fern Stauropteris are described from permineralized peat associated with Lower-Middle Pennsylvanian coal deposits of southeastern Kentucky. This represents the first documented report of the genus in North America. The specimens are regarded as representatives of a new species—S. biseriata—based on the distinctive branching habit. Three branch orders are described, and in each case, branches are singular and distichous, arranged in a two-ranked pattern. This is in contrast to other species of Stauropteris in which the branches are paired and form a quadriseriate pattern. A pair of vascularized aphlebiae subtend each branch through all branching orders. Aphlebiae associated with first- and second-order branches are three-parted at the point of insertion; those that subtend third-order branches are singular. Stauropteris and a number of Devonian fern-like plants are compared on the basis of certain morphological similarities.  相似文献   

18.
Klaus Hägele 《Chromosoma》1977,59(3):207-216
Two Giemsa banding methods (C banding and RB banding) are described which selectively stain the centromere bands of polytene salivary gland chromosomes in a number of Chironomus species. — By the C banding method the polytene chromosome appearance is changed grossly. Chromosome bands, as far as they are identifiable, are stained pale with the exception of the centromere bands and in some cases telomeres, which then are intensely stained reddish blue. — By the RB method the centromere bands are stained bright blue, whereas the remainder of the polytene bands stain red to red-violet. — Contrary to all other species examined, in Chironomus th. thummi numerous interstitial polytene chromosome bands, in addition to the centromere regions, are positively C banded and blue stained by RB banding. In the hybrid of Ch. th. thummi x Ch. th. piger only those interstitial thummi bands which are known to have a greater DNA content than their homologous piger bands are C banding positive and blue stained by the RB method whereas the homologous piger bands are C banding negative and red stained by RB banding. Ch. thummi and piger bands with an equal amount of DNA both show no C banding and stain red by RB banding. — It seems that the Giemsa banding methods used are capable of demonstrating, in addition to centromeric heterochromatin, heterochromatin in those interstitial polytene chromosome bands whose DNA content has been increased during chromosome evolution.  相似文献   

19.
The Japanese species of the genus Agraphydrus are revised. Five species are recognized, including Agraphydrus ogatai sp. nov. from Honshu, Shikoku and Kyushu. The new species can be distinguished by the coarse ground punctures on the pronotum and elytra, and by the shape of parameres. All species except A. luteilateralis are redescribed. All species are diagnosed, relevant morphological characters are illustrated, distributional records are summarized and an updated key is provided.  相似文献   

20.
Total patterns of water-soluble proteins of 35 strains (7 species) of Galactomyces and Dipodascus strains with their respective Geotrichum anamorphs are compared. Quantitative differences among a number of species are found with iso-electric focusing; bands that characterize species are selected. Qualitative differences are found between the teleomorph genera.  相似文献   

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