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1.
A new species, Acantholimon avanosicum Dogan & Akaydin in the Plumbaginaceae is described and illustrated. The species grows on argillaceous slopes in Central Anatolia, Turkey. The diagnostic morphological characters that distinguish it from closely related taxa are discussed. A revised key to Acantholimon species in Turkey with densely distichous simple spikes is presented. © 2002 The Linnean Society of London, Botanical Journal of the Linnean Society , 2002, 138 , 365–368.  相似文献   

2.
In order to provide new insights into phylogenetic relationships among the neotropical taxa of Phyllanthus , 28 illustrations are provided of the pollen grains of 22 selected species studied from 11 sections of the subgenera represented in the neotropics. Special attention has been given to subgenus Conami because of its variability in pollen morphology: of eight species illustrated, the apertures are diploporate colpi in three species and pores in five species; exine ornamentation is vermiculate in two species and pilate in the other six species. The six species in the neotropical sections Pityrocladus and Microglochidion (subgenus Emblica ) are characterized by prolate grains with an increased number of colpi (4–8). Of particular interest are species in which the pollen exine is clypeate (with exine shields); clypeate pollen grains are illustrated in two species of subgenus Xylophylla and in one species of section Cyclanthera that has unique exine shields with single central pila. The pollen of the one Brazilian phylloclade-bearing species illustrated (in section Choretropsis ) has 3-colporate grains with reticulate exine, typical for subgenus Phyllanthus , and very different from the clypeate grains of the West Indian phylloclade-bearing species in section Xylophylla . This pollen evidence clearly demonstrates homoplasy in the origin of phylloclades in Phyllanthus . Pollen morphological data suggest that the neotropical taxa of Phyllanthus have arisen following colonization from Africa (subgenus Kirganelia ) and Asia (subgenus Emblica ). © 2002 The Linnean Society of London, Botanical Journal of the Linnean Society , 2002, 138 , 325–338.  相似文献   

3.
4.
The lizard family Chameleonidae is one of the most distinctive taxa of all vertebrates. Nonetheless, despite great intrafamilial diversity, little research has been conducted on morphological variation among chameleons. As a first step in this direction, we took morphological measurements on the head, limbs, spines, and tail of 56 species. Our goals were to investigate whether morphological variation correlates with differences in ecology and to examine whether correlations exist among different aspects of morphology. Based on existing information, species were classified either as arboreal or terrestrial, the latter referring to species that are known to use the ground on a regular basis. This study confirms that considerable intrafamilial variation exists among chameleons and that these traits appear to be evolutionarily quite labile. Once the effects of size are removed, functionally related traits tend to covary; however, few correlations are observed between non-functionally related traits. Many differences in the lengths of the limbs and head elements were detected between terrestrial and arboreal species, but the functional and selective significance of these differences is not clear. Further research on chameleon behaviour and ecology is required to understand the factors contributing to chameleon morphological diversity. © 2002 The Linnean Society of London, Biological Journal of the Linnean Society , 2002, 76 , 91–103.  相似文献   

5.
Despite the many studies that have investigated successful establishment of introduced bird species, very little is known about the patterns of success worldwide and the influence of life history and ecological traits. This study describes the analysis of non-native land bird introductions to test existing hypotheses of establishment success using a modern comparative approach to control for phylogenetic relatedness among taxa. I used randomization tests, permutational phylogenetic regressions, and across-taxa and sister-taxa comparisons to examine predicted correlates of introduction success. My analyses confirmed that the variability in establishment success among introduced land bird families is distributed in a manner significantly different from a random process, and that life history and ecological attributes are an important influence of introduction success. I found strong evidence, through a generalized linear model, that increased habitat generalism, lack of migratory tendency, and sexual monochromatism together explain significant variation in the successful establishment of introduced land bird species. This has resulted in a predictive equation for the novel introduction of land bird species.  © 2002 The Linnean Society of London, Biological Journal of the Linnean Society , 2002, 76 , 465–480.  相似文献   

6.
A multivariate analysis to differentiate morphologically the populations of wild potatoes Solanum cardiophyllum ssp. cardiophyllum and S. cardiophyllum ssp. ehrenbergii was carried out. An analysis of the morphology and the viability of pollen of these potato populations was also made. The results of the morphometric analysis indicate that both subspecies are phenetically different. The pollen grain shape and size in ssp. cardiophyllum are different in northern and southern populations. Pollen diameter is significantly different between subspecies. Based on these results we propose that these taxa should be considered as two separate species.  © 2002 The Linnean Society of London, Botanical Journal of the Linnean Society , 2002, 140 , 415–426.  相似文献   

7.
With the use of isozymes and PCR-fingerprinting analysis molecular markers were found between the varieties Pleurotus eryngii var. eryngii and P. eryngii var. ferulae within the Pleurotus eryngii complex, which allowed the identification of the fruitbodies collected in Southern and Central Italy. The study of sympatric localities has shown that there is no gene exchange between them in the field. The post-mating barriers between these taxa are not yet completely efficient. However, in the field the gene pools of the two taxa appear isolated and associated with specific host plants: Eryngium campestre and Ferula communis . On the basis of the genetic and ecological differences observed and given the absence of gene exchange in sympatric localities, P. eryngii and P. ferulae are to be considered distinct biological species. © 2002 The Linnean Society of London, Biological Journal of the Linnean Society , 2002, 75 , 125–136.  相似文献   

8.
The resupinate leaves of 16 species of Alstroemeriaceae were examined using light- and scanning electron microscopy. The leaf anatomy is described for all of the species, that of the petiole and stem for selected species. The mesophyll consists of chlorenchyma and includes idioblasts that contain raphides. Dorsiventral, isolateral or isobilateral leaf types were observed. Petioles are always isolateral. Two epidermal types are commonly observed: type I contains jigsaw puzzle-like intercostal cells and longitudinally elongated cells above the veins; type II contains only longitudinally elongated cells, usually longer, above the veins. Some species have an epidermis which differs from the main types. All species show adaptation to resupination by having an inverted anatomy. Due to the twist of the leaves, adaxial indicates the lower surface and abaxial the upper. Stomata are found on both surfaces. Palisade cells, when they occur, are always on the abaxial surface. Most species are mesomorphic in spite of the dry environments in which they grow; a few show xeromorphic features. The leaves are compared and discussed with relation to ecological conditions.  © 2002 The Linnean Society of London, Botanical Journal of the Linnean Society , 2002, 140 , 261−272.  相似文献   

9.
During the preparation of a World Rubiaceae Checklist , numerous unplaced taxa were encountered, including illegitimate and invalid names, and species for which generic placement is uncertain. In this contribution, 35 new combinations and 20 new names are proposed, and the names of three taxa are validated.  © 2008 The Linnean Society of London, Botanical Journal of the Linnean Society , 2008, 157 , 115–124.  相似文献   

10.
The chromosome numbers are given for 20 angiosperm taxa, most of which grow predominately or exclusively on serpentine in Greece, and the karyotype morphology is illustrated in all cases but one. Chromosome data are provided for the first time for ten taxa ( Alyssum pogonocarpum, Centaurea charrellii, C. vlachorum, Cephalaria fanourii, Matricaria tempskyana, Onosma stridii, Scorzonera doriae, Silene fabarioides, S. salamandra, Trinia glauca ssp. pindica ) and for the endemic monospecific genus Leptoplax . A new number is reported for Thymus teucrioides ssp. candilicus . An unexpected dysploid number is recorded for a population of Leontodon hispidus ssp. hispidus. Chromosome number and karyotype details from Greek populations are presented for the rest of the taxa. Chromosomal evidence supports close relationships among members of Onosma subsect. Asterotricha . The unusual chromosome number of Centaurea vlachorum supports its placement either in C. sect. Jacea or C . sect. Cyanus . The evolution of taxa in sections Vierhapperia, Pulvinares , and Nervosae of Scorzonera appears to be connected with particular chromosomal rearrangements and dysploidy. Leptoplax does not share the same chromosome number with Peltaria but with Bornmuellera instead, something that facilitates infrageneric hybridization. Further issues of taxonomy, distribution, evolution and conservation of serpentine species are briefly discussed where appropriate. © 2002 The Linnean Society of London , Botanical Journal of the Linnean Society , 2002, 139 , 109–124.  相似文献   

11.
Four new species of Pleurosigma are described from the region of Alexandria in Egypt: P. williamsii sp. nov. , P. mariutensis sp. nov. , P. ramlehensis sp. nov. and P. rushdyensis sp. nov. The taxa had been previously misidentified as P. rigidum W. Sm., P. elongatum W. Sm., P. speciosum var. sumatricum H. Perag. and P. formosum W. Sm., respectively. Due to the close resemblance of P. williamsii, P. mariutensis , P. ramlehensis and P. rushdyensis to P. rigidum , P. elongatum , P. speciosum var. sumatricum and P. formosum and the lack of good illustrations of these previously described species, their valvar features are shown and discussed in relation to the new taxa. © 2002 The Linnean Society of London, Botanical Journal of the Linnean Society , 2002, 140 , 77–92.  相似文献   

12.
Genetic relationships among 24 Italian and Adriatic populations of barbs (genus Barbus ) were assessed using electrophoretic analysis of allozymes and mitochondrial DNA sequences of the cytochrome b gene. Results obtained with both markers were concordant, but they were not congruent with the current morphology-based systematics and taxonomy. Populations assigned to the same nominal taxa ( B. caninus , B. petenyi and B. rebeli ), were very divergent in both allozymes and mtDNA, indicating that these populations deserve recognition as different units for conservation and management. On the other hand, the two fluvio-lacustrine taxa considered as distinct species (i.e. B. plebejus and B. tyberinus ) are genetically very close to each other, showing no clear differences at either allozymes or mtDNA. The population of B. caninus from Pellice River carried allozyme alleles and mtDNA specific for B. plebejus , indicating a genetic introgression towards the former species. © 2002 The Linnean Society of London, Biological Journal of the Linnean Society , 2002, 75 , 83–99.  相似文献   

13.
Studies in the areas of comparative morphology and palynology of the genus Cyclamen L. (Primulaceae) are outlined, and used in combination with observations and analyses of past works and publications and of field data (gathered by the Cyclamen Society and others) to generate new data sets. These are subject to cladistic parsimony analysis for the entire genus, and to phenetic ordinal analysis for subgenus Gyrophoebe O.Schwarz, to reach a conclusion on the validity of the latter classification, and the separation of taxa within it. A phylogeny and subgeneric reclassification is proposed with the reinstatement of Cyclamen elegans Boiss. & Buhse at species level based on the results gathered. © 2002 The Linnean Society of London, Botanical Journal of the Linnean Society , 2002, 138 , 473–481.  相似文献   

14.
The Compositae (Asteraceae) is the largest flowering plant family if described, accepted taxa are considered. Recent revisions in the taxonomy of the family have resulted in the recognition of ten subfamilies and 35 tribes. The tribe Arctotideae is one of the smallest, with around 200 species; it contains two subtribes and several hard-to-place taxa. Previous work has shown that the subtribe Arctotidinae is well defined and is restricted to southern Africa, except for the Australian genus Cymbonotus . Molecular data from internal transcribed spacer (ITS), ndh F, and trn L-F sequences were used (24 previously published sequences; 47 new sequences) to determine the patterns of relationships within the subtribe. Twenty-three samples from the ingroup, including members of all genera and all three species of Cymbonotus , were included in the analysis, together with two outgroup taxa. Cymbonotus is monophyletic and deeply embedded in the subtribe; Haplocarpha is paraphyletic and basal in position; all other genera are monophyletic; however, Arctotis has over 60 species and only eight were sampled for this study, so additional work may prove otherwise. Arctotis is nested high in the tree and has short branch lengths; this may reflect recent radiation. By contrast, the species of the paraphyletic and basal Haplocarpha have long branches, which may indicate an older radiation and a shared ancestry with the remainder of the subtribe. The presence of Cymbonotus in Australia is most probably the result of long-distance dispersal.  Journal compilation © 2007 The Linnean Society of London, Botanical Journal of the Linnean Society , 2007, 153 , 1–8. No claim to original US government works  相似文献   

15.
Body size and body shape are tightly related to an animal's physiology, ecology and life history, and, as such, play a major role in understanding ecological and evolutionary phenomena. Because organisms have different shapes, only a uniform proxy of size, such as mass, may be suitable for comparisons between taxa. Unfortunately, snake masses are rarely reported in the literature. On the basis of 423 species of snakes in 10 families, we developed clade‐specific equations for the estimation of snake masses from snout–vent lengths and total lengths. We found that snout–vent lengths predict masses better than total lengths. By examining the effects of phylogeny, as well as ecological and life history traits on the relationship between mass and length, we found that viviparous species are heavier than oviparous species, and diurnal species are heavier than nocturnal species. Furthermore, microhabitat preferences profoundly influence body shape: arboreal snakes are lighter than terrestrial snakes, whereas aquatic snakes are heavier than terrestrial snakes of a similar length. © 2012 The Linnean Society of London, Biological Journal of the Linnean Society, 2012, ●● , ●●–●●.  相似文献   

16.
In Cyclamen subgenus Psilanthum , previous authors have recognized three species ( C. repandum, C. balearicum and C. creticum ), with C. repandum subdivided into three subspecies (ssp. repandum , ssp. peloponnesiacum and ssp. rhodense ), and two varieties (var. vividum and var. peloponnesiacum ) within C. repandum ssp. peloponnesiacum . To examine the validity of this classification and the degree of morphological differentiation among closely related endemic taxa with disjunct distributions, we undertook analyses of three quantitative and eight qualitative morphological traits of flowers and leaves, most of which have previously been used without statistical comparison in the classification of the different taxa. Cyclamen balearicum showed high levels of morphological differentiation from all other taxa in subgenus Psilanthum consistent with its specific status. In contrast, morphological differentiation between C. creticum and subspecies of C. repandum was similar to that among the three subspecies of C. repandum . When compared with a recent molecular phylogeny of this subgenus, our results suggest that C. creticum may best be described as a geographical subspecies of C. repandum . The two varieties of C. repandum ssp. peloponnesiacum showed few significant differences for individual traits and their overall morphology is very similar to each other. The morphology of plants at three sites on Corsica strongly suggest, consistent with molecular data, the occurrence of hybrid populations between C. balearicum (outside of its previously recognized distribution) and local C. repandum .  © 2002 The Linnean Society of London, Botanical Journal of the Linnean Society , 2002, 139 , 133–144.  相似文献   

17.
The sclerophyllous, evergreen vegetation found in Mexico under tropical climate is named 'Mexical' (MEX) and presents many traits that have been thought to converge under a Mediterranean climate. Flowering phenology is strongly similar across Mediterranean-type ecosystems (MTEs) and this paper investigates MEX plant phenology in this context. The common history of the vegetation and the differences in the climatic conditions experienced by MEX and MTE taxa provide an ideal scenario to infer the relative importance of natural selection and historical constraints in the phenological response of plants to climatic conditions. This study has involved collecting field and bibliographic data on flowering phenology of MEX communities to detect (1) similarities at the community level between MTEs and MEX, (2) similarities between Tertiary and Quaternary taxa in MTEs and MEX, and (3) similarities between congeneric taxa from MEX and MTEs (taxa sharing a common ancestor but having evolved under different climates). Flowering in MEX does not occur mainly in spring, as in MTEs, but in summer, suggesting a response that maximizes water use in the rainy season. Flowering phenology of MEX species differed from their MTE congeneric species, suggesting that even though a common ancestor is shared, environmental pressures have led to different phenological responses in MEX and MTE plants. The flowering season for species that originated in the Tertiary and Quaternary did not differ in MEX, as expected, because of climatic uniformity along the whole time line. In MTEs, flowering differences between Tertiary and Quaternary species were not congruent, suggesting that the balance between the historical constraints and the selective force of the Mediterranean climate is different among the three MTEs, and a particular explanation is needed for each. © 2002 The Linnean Society of London, Botanical Journal of the Linnean Society , 2002, 138 , 297–303.  相似文献   

18.
As a result of extensive collections and subsequent determinations made in recent years through most regions of Iran (now preserved in herbarium TARI), three new species of Echinops ( E. longipenicillatus, E. procerus and E. shahrudensis ) are described and illustrated. All belong to E . sect. Oligolepis Bunge, which is endemic to Iran.  © 2002 The Linnean Society of London, Botanical Journal of the Linnean Society , 2002, 140 , 181–186.  相似文献   

19.
Assumptions about the host and stratum specificity of tropical insects are routinely incorporated into estimates of global species richness, but few empirical studies reliably assess tropical insect specificity. In French Guiana, cerambycid beetles in the genus Palame reproduce exclusively in trees belonging to the Brazil nut family (Lecythidaceae). During a year-long rearing project, Palame anceps (Bates) emerged exclusively from a single host species, but P. crassimana Bates and P. mimetica Monné appeared to make seasonal changes in host affiliation. In the case of P. crassimana , dry season specimens could be distinguished from rainy season specimens by subtle differences in pubescence, but it was difficult to find diagnostic morphological characters supporting their delimitation as separate species. In order to detect genetic differentiation in Palame , 1049 bp of mitochondrial DNA (COI gene) were sequenced. The three nominal species of Palame yielded six haplotype groups, with sequence divergences among groups ranging from 8.27 to 17.56%. Species with apparent seasonal changes in host use included multiple distinct haplotype groups that I interpret to represent multiple species-level taxa. Insects considered generalized owing to temporal or geographical changes in host association may, with improved resolution in species limits, prove to be assemblages including relatively specialized cryptic species. © 2002 The Linnean Society of London, Biological Journal of the Linnean Society , 2002, 76 , 195–209.  相似文献   

20.
Two new species ( Neuropteris terminiscus and N. kneuperi ) are described from the Bolsovian ('Westphalian C') of Saarland. N. terminiscus had previously been misidentified as Paripteris pseudograndinioides , but the pinnae are clearly imparipinnate and thus cannot belong to that morphogenus. N. kneuperi had previously been misidentified as Neuropteris obliqua and N. heterophylla , both which appear to be absent from Saar-Lorraine. This is considered further evidence of the distinctive nature of the Westphalian vegetation of the Saar-Lorraine Basin, especially among the seed-plants.  © 2002 The Linnean Society of London , Botanical Journal of the Linnean Society , 2002, 139 , 193–205.  相似文献   

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