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1.
A morphological study of specimens collected by the author and a critical revision of the key herbarium collections revealed a new rather peculiar taxon of Alchemilla occurring in almost every region of the Middle Volga basin, Russia. This novelity is here described as A. schmakovii and images of the principal morphological features of this species are provided. The new species is compared with related species in A. sect. Alchemilla (e.g. A. micans) and sect. Plicatae (e.g. A. breviloba) based on morphological characteristics.  相似文献   

2.
The author describes four new apomict species ofAlchemilla L. ser.Hirsutae H. Lindb. They appear to be endemic in the Western Carpathians, growing there on some few mountain ranges, mostly in synanthropic habitats. Their known distribution areas seem to be ± separate. Two numerical indices called the epicalyx index and the hypanthium index respectively are defined to characterise the proportion of anAlchemilla flower. Ranges of both indices are shown for each of the new species.  相似文献   

3.
This paper presents the results of karyological analysis of seven Alchemilla species collected from north-east Anatolia, Turkey, belonging to Alchemilla sect. Alchemilla subsect. Heliodrosium ser. Vulgares and subsect. Calycanthum ser. Elatae and ser. Calycinae. The following chromosome numbers were determined: A. haraldi 2n = 85–105, A. heterophylla 2n = 85–97, A. hirtipedicellata 2n = 86–100, A. oriturcica 2n = 86–102, A. persica 2n = 78–99, A. procerrima 2n = 69–78 and A. trabzonica 2n = 78–88. The chromosome numbers of three of these seven species are presented for the first time.  相似文献   

4.
A new species of Alchemilla L. (Rosaceae), A. reflexa Frost‐Ols., is described and illustrated. A. reflexa is characterized by deflexed indumentum on petioles and stems, orbicular leaves with imbricate basal lobes and crimson‐magenta coloured basal stipules. It is distributed in the Massif Central, France, where it is widespread, and in northeastern Pyrenees (déps. Ariège and Aude). A. reflexa is compared with two species previously recorded from the Massif Central with doubt, A. exigua Buser and A. strigosula Buser and with A. filicaulis Buser that can be misidentified as A. reflexa in the field. An introduction to past treatments of Alchemilla in the Massif Central is provided as well as a discussion of some morphological elements used for delimiting Alchemilla taxa.  相似文献   

5.
We synthesized the results from a flow cytometric seed screen and the literature to infer the phylogenetic origin and the geographical and taxonomic distribution of apomixis in tribe Potentilleae (Rosaceae). We distinguished between regular sexuality and apomixis, the zygotic and parthenogenetic origin of the embryo, and the pseudogamous (i.e. sexual) versus autonomous origin of the endosperm. The combined evidence provides information on reproductive modes for 11 genera and 120 species. For the first time records on reproductive mode are provided for the genus Farinopsis, 29 species (from five genera), and seven series of Potentilla. Regular sexuality was observed in Aphanes, Argentina, Comarum, Dasiphora, Drymocallis, Farinopsis, Fragaria, Horkeliella, Potentilla, and Sibbaldia. Reliable evidence for apomixis is restricted to two evolutionary lineages of Potentilleae: the Potentilla core group and Alchemilla/Aphanes. Early evolutionary divergence of these lineages (approximately 50 Mya), characterized by pseudogamous and autonomous apomictic seed formation, respectively, suggests parallel origins of apomixis. Apomixis is shown to be taxonomically widespread in the whole Northern Hemisphere distribution range of Potentilla, a pattern that is explained by hybrid transfer and repeated intercontinental dispersals. Taxonomic and geographical coverage is discussed with reference to species diversity centres of genera. © 2014 The Linnean Society of London, Botanical Journal of the Linnean Society, 2015, 177 , 214–229.  相似文献   

6.
Apomictic microspecies, for example those of the genus Alchemilla, are often difficult to distinguish. Still, their differences are thought to be persistent due to apomixis. Apomicts are argued to have general-purpose genotypes. The present study aims to assess the variation of morphological characters of Alchemilla depending on environmental conditions both in nature and experimentally; to evaluate the efficacy of characters for identifying the different microspecies; to assess the similarity of different microspecies; and to determine if Alchemilla microspecies have general-purpose genotypes that are not dependent on environmental conditions. The variability of selected characters in seven microspecies of Alchemilla was studied in nature and five microspecies were grown in a common garden experiment. The growing conditions of the latter were subjected to various manipulations (fertilization, shading and irrigation). Typical natural habitats of Alchemilla exhibited only small differences. Environmental conditions therefore had little effect on morphological characters. Neither cultivation in the common garden nor manipulation of conditions therein had a significant impact on the discrimination of microspecies. However, the metric characters were larger in the garden relative to those observed in nature, particularly under fertilization. Fertilization affected most characters, whereas shading and irrigation did not. The most effective characters for discriminating between microspecies were the ratios of the metric characters. Two species pairs: A. vulgaris and A. micans, as well as A. glaucescens and A. hirsuticaulis were morphologically close; however, the species within these pairs could still be distinguished. The morphological characters of Alchemilla microspecies were only slightly dependent on the environmental conditions.  相似文献   

7.
The composition of isolated floras has long been thought to be the result of relatively rare long-distance dispersal events. However, it has recently become apparent that the recruitment of lineages may be relatively easy and that many dispersal events from distant but suitable habitats have occurred, even at an infraspecific level. The evolution of the flora on the high mountains of Africa has been attributed to the recruitment of taxa not only from the African lowland flora or the Cape Floristic Region, but also to a large extent from other areas with temperate climates. We used the species rich, pan-temperate genera Carex, Ranunculus and Alchemilla to explore patterns in the number of recruitment events and region of origin. Molecular phylogenetic analyses, parametric bootstrapping and ancestral area optimizations under parsimony indicate that there has been a high number of colonization events of Carex and Ranunculus into Africa, but only two introductions of Alchemilla. Most of the colonization events have been derived from Holarctic ancestors. Backward dispersal out of Africa seems to be extremely rare. Thus, repeated colonization from the Northern Hemisphere in combination with in situ radiation has played an important role in the composition of the flora of African high mountains.  相似文献   

8.
The origin and early development of procambium and associated ground meristem of major and minor veins have been examined in the leaf blades of seven C4 grass species, representing different taxonomic groups and the three recognized biochemical C4 types (NAD-ME, PCK, and NADP-ME). Comparisons were made with the C3 species, Festuca arundinacea. In “double sheath” (XyMS+) species (Panicum effusum, Eleusine coracana, and Sporoboìus elongatus), the procambium of major veins gives rise to xylem, phloem, and a mestome sheath; associated ground meristem differentiates into PCA (“C4 mesophyll”) tissue and the PCR (“Kranz”) sheath. Development in the C3 species parallels this pattern, except that associated ground meristem differentiates into mesophyll and a parenchymatous bundle sheath. In contrast, major vein procambium of “single sheath” (XyMS–) species (Panicum bulbosum, Digitaria brownii, and Cymbopogon procerus) differentiates into xylem, phloem and a PCR sheath; associated ground meristem gives rise to PCA tissue. These observations of major vein development support W. V. Brown's hypothesis that the PCR sheaths of “double sheath” (XyMS+) C4 grasses are homologous with the parenchymatous bundle sheaths of C3 grasses, while in “single sheath” (XyMS–) C4 species they are homologous with the mestome sheath. Although there are some similarities in the development of the major and minor vascular bundle procambium in the C4 species examined, the ontogeny of the smaller minor veins is characterized by a precocious delineation of the PCR sheath layer that may even precede the appearance of the distinctive cytological features of ground meristem and procambium. This contracted development in minor veins appears to be related to their close spacing in mature leaves and to their comparatively late appearance during leaf ontogeny.  相似文献   

9.
This paper presents the results of a karyological analysis of 14 species ofAlchemilla L. collected from SW Europe (Spain and French Pyrenees). About 75% of the analyzed species have chromosome numbers 2n = 95–136. A few species have lower chromosome numbers. The chromosome numbers of 13 species are presented for the first time.  相似文献   

10.
Summary

Alchemilla acutiloba Opiz was found growing on disused railway sidings 5 km north of Glasgow. In the light of its known northern English and Scandinavian distribution and ecology, the status of this newly discovered Scottish Alchemilla is discussed.  相似文献   

11.
Abstract

This paper provides faunistic information about almost a hundred different species and subspecies of Jewel Beetles (Coleoptera: Buprestidae) including the subfamilies Julodinae, Acmaeoderinae, Polycestinae, Chalcophorinae and Buprestinae (except the genus Anthaxia) which have been found in the Near East. It also gives a survey of the literature concerning the Jewel Beetles of this region. There are photographs of l8 species. As the author intends to continue the list, he is interested in further information and offers assistance with identifications.  相似文献   

12.
Abstract

The author reports the results of the herborizations carried out on the island Piana (northeastern Sardinia) located between Cape Ceraso and Cape Coda Cavallo. The flora consists of 250 entities distributed in 154 genera, inclusive of 54 families. The author gives information regarding the mail features of the vegetal coverage, and points out the presence of two species: Limonistrum monopetalum (L.) Boiss. and Omithoga-lum arabicum L., which are extremely rare in the little islands.  相似文献   

13.
首次报道了西藏2个新记录属,蔷薇科(Rosaceae)的羽衣草属(Alchemilla)和鸢尾科(Iridaceae)的庭菖蒲属(Sisyrinchium),并报道2个新记录种,即无毛羽衣草(Alchemilla glabra Neygenf.)和庭菖蒲(Sisyrinchium rosulatum Bickn.)。  相似文献   

14.
Spider ants of the genus Leptomyrmex Mayr (Hymenoptera: Formicidae: Dolichoderinae) are conspicuous species of Australasian rainforests, with putative fossil relatives in the Neotropics and Europe. There is longstanding debate over the biogeographical history of the genus, with the Palaearctic and Neotropical regions proposed as alternate centres of origin. We propose a resolution of this debate with the recent discovery and analysis of an extant species from central Brazil, L. relictus sp.n. , which we describe from workers, males and brood. We sequence ten nuclear genes in the new species and in several Australian Leptomyrmex species, and append these data to a 54‐taxon, 10‐gene data matrix previously generated for the subfamily Dolichoderinae. We conduct phylogenetic and divergence dating analyses, and re‐evaluate the fossil record of the group. We recover Leptomyrmex relictus sp.n. as a member of the Leptomyrmex clade with high support. It is sister to the Australasian species, and the genus Leptomyrmex is, in turn, sister to a pair of Neotropical genera, Forelius and Dorymyrmex. We infer a Neotropical origin for the genus and estimate a mid‐Eocene (46 Ma, 95% CI 56 to 36 Ma) origin for the crown genus and an Oligocene origin for the Australasian clade (29 Ma, 95% CI 40 to 19 Ma). We confirm placement of the Dominican amber species ?L. neotropicus Baroni Urbani in the genus but reject a close relationship with the Palaearctic fossil taxa ?Leptomyrmula Emery and ?Usomyrma Dlussky, Radchenko & Dubovikoff, considering them incertae sedis in the subfamily (Dolichoderinae). In contrast to the mesophilic preferences of the Australasian species of Leptomyrmex, the new Brazilian species inhabits cerrado (dry savannah). Our results support a Neotropical origin for spider ants with dispersal to Australia. Rafting on west‐bound currents and/or a historical diversity imbalance between Australia and South America are proposed as alternate hypotheses to explain a pattern of biased E–W mid‐Tertiary dispersal for ants with austral distributions. This pattern is suggested by our results in conjunction with observations of other ant clades. Overall, our findings highlight the value of integrated taxonomy, critical interpretation of morphology, and a comparative phylogenetic framework when conducting palaeontological and biogeographical studies of insect species. This published work has been registered in ZooBank, http://zoobank.org/urn:lsid:zoobank.org:pub:6E9E6617‐6E53‐40B8‐82C7‐67F89A83C553 .  相似文献   

15.
Summary

The occurance of Buxus balearica Willd. in Sardinia, already reported by Gennari (1864), and its indigenous state are confirmed by the present study. Its station and geographic distribution as well as the biocenosis in which this species takes part (Barbusi near Sulcis in S. Sardinia) are considered.

The study of the Barbusi station, in comparison with others hitherto known, brings a general confirmation to Chiarugi's view concerning the mountainous origin of the mediterranea elements. Besides, it emphasizes the differences between the stations of B. balearica, an element of the mediterranea “macchia”, and those of B. sempervirens, an undergrowth element of mesophilous formations (deciduous woods), which only rarely belonges to more termophilous bioceneses.

The author notes that both species belong to the same stage of Q. Ilex and that the altitude range in which the Q. Ilex stage is comprised is very wide in the different mediterranean regions. In addition, the author emphasizes that Buxus sempervirens occurs in Corsica and Atlas up to the upper limit of Quercetum Ilicis, together with species belonging to higher stages, whilst Buxus balearica belongs to the lower limit of Quercetum Ilicis in the underzone “Olea-Ceratonia”. The altimetric separation of these species is, therefore, obvious.

Due to the compenetration of floras of mountainous origin during the phases of the Ice-period, the knowledge of the segregation epoch of these species from each other is made impossible.

Buxus balearica occupies actually as eocene substratum and, therefore, shows edaphic exigences for soils of a certain age: a condition not occurring for Buxus sempervirens.

Both Buxus species, together with other horeal-tertiary ones (all constituting actually, in the mediterranea countries, a special relict flora) belong to the Lauretum, in a historic sense (Chiarugi).  相似文献   

16.
Silvia Zenari 《Plant biosystems》2013,147(2-4):252-286
Summary

The author gives notice, for the first time, of the presence of Juniperus Sabina L. in the Passiria Valley (Alto Adige); she describes its distribution both in this valley and in the Vizze Valley carefully and from the comparison between the floristic composition of its phytocenoses in both valleys, she concludes that the various species living with J. Sabina are associated with it only because they find in its shrubs suitable life conditions. On the whole even for this phytocenosis, as for the others which can develope in chemically different substrata and spread in altitude remarkably, the known «companions» depend on the kind of the soil most of them belong to the flora typical of the single altitudinal belts and horizons on which the association develop unless particular local conditions permit the infiltration of some species belonging to different altitudinal belts as in one of the stations examined by the author in the Passiria Valley.  相似文献   

17.
W. Hempel 《Feddes Repertorium》1971,81(10):657-686
This work presents an investigation of the author on the systematical position of Melica uniflora Retz. and Melica rectiflora Boiss. et Heldr. The author proves the affinity of these Melica-species to those of the pacific-northamerican territories. The usefulness of striking characteristic features or signs (e. g.: the cilia (fringes) and the awns of the glumelles) is examined in respect to their taxonomic value; and the corresponding literature is discussed. The author proves that certain characteristic signs, hardly or not yet being noticed till now, play a decisive role in respect to the explanation of the affinity between the species Melica L.; the probative force of these features will not become evident but by comparison of the taxa of all continents. Following the author, the storage internodes, the formation of antiligula in front of the leaf-base, and the dynamics in the ontogeny of the elements of the spikelets (glumes) are thought to be very important characteristics of organization. The author compares these features these with their formation within the range of sub-genus Melica. As a result of this research, the new sub-genus Bulbimelica is described and its systematical classification is given. The new subgenus is furthermore more exactly separated from the subgenus Melica. The classification is followed by chorological interpretation as well as by indications to the ecology of the taxa and the distribution of diagnostically important signs within the whole generic distribution-area.  相似文献   

18.
Macromorphological variation within theOrnithogalum umbellatum L. (Hyacinthaceae) complex in France was studied. The resulting data were treated by numerical taxonomy methods. Three morphs can be identified: one corresponding to diploid plants, another made up of triploids and a third which encompasses plants having ploidy level above 3x (4x, 5x, and 6x). A systematic interpretation of the complex is proposed wherein only one species,O. umbellatum, is retained. This species corresponds to a polyploid complex undergoing evolution.  相似文献   

19.
The paper `A taxonomic revision of the genus Taenia Linnaeus, 1758 s. str.' (Verster, 1969) gives concise characterisations, together with drawings of rostellar hooks and the terminal genital organs, of the 32 Taenia species and three subspecies which this author found to be valid. Yet, it is hardly possible to quickly identify a questionable species or to readily access information on their hosts, geographical range and synonyms. The present paper compiles these data and additional information on larval characteristics into tables. Measurements and numbers of hooks are shown using a graph. Additional data are included from authors not mentioned by Verster and for seven new species (T. dinniki, T. jaipurensis, T. kotlani, T. madoquae, T. saigoni and T. simbae), two re-validated species (T. krepkogorski, T. retracta) and two subspecies (T. polyacantha arctica and T. saginata asiatica) described since 1969. Reasons for rejecting one new species and one new subspecies are given. A table of definitive hosts and the Taenia species occurring in them is also included, as is one of synonyms from 1850 onwards. A good procedure for the staining and mounting of cestodes is described.  相似文献   

20.
A remarkable diversity of venom peptides is expressed in the genus Conus (known as “conotoxins” or “conopeptides”). Between 50 and 200 different venom peptides can be found in a single Conus species, each having its own complement of peptides. Conopeptides are encoded by a few gene superfamilies; here we analyze the evolution of the A-superfamily in a fish-hunting species clade, Pionoconus. More than 90 conopeptide sequences from 11 different Conus species were used to build a phylogenetic tree. Comparison with a species tree based on standard genes reveals multiple gene duplication events, some of which took place before the Pionoconus radiation. By analysing several A-conopeptides from other Conus species recorded in GenBank, we date the major duplication events after the divergence between fish-hunting and non-fish-hunting species. Furthermore, likelihood approaches revealed strong positive selection; the magnitude depends on which A-conopeptide lineage and amino-acid locus is analyzed. The four major A-conopeptide clades defined are consistent with the current division of the superfamily into families and subfamilies based on the Cys pattern. The function of three of these clades (the κA-family, the α4/7-subfamily, and α3/5-subfamily) has previously been characterized. The function of the remaining clade, corresponding to the α4/4-subfamily, has not been elucidated. This subfamily is also found in several other fish-hunting species clades within Conus. The analysis revealed a surprisingly diverse origin of α4/4 conopeptides from a single species, Conus bullatus. This phylogenetic approach that defines different genetic lineages of Conus venom peptides provides a guidepost for identifying conopeptides with potentially novel functions.  相似文献   

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