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1.
Clivia robusta B.G. Murray, Ran, de Lange, Hammett, Truter et Swanevelder sp. nov. (Amaryllidaceae) is a tubular, pendulous-flowered Clivia species, restricted to the Pondoland Centre of Endemism, South Africa. The unique morphology, distribution, karyotype and molecular fingerprint distinguish it from all other pendulous-flowered species in the genus.  © 2004 The Linnean Society of London, Botanical Journal of the Linnean Society , 2004, 146 , 369–374.  相似文献   

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Some aspects of the natural history of snakes of the colubrid genus Natrix have been well studied. With their extensive European distribution and relative abundance, their ecology, reproduction and behaviour are well known. Yet other facets of their biology remain poorly understood. These include knowledge of Natrix phylogeny, hypotheses explaining the current distribution of the three extant members of the genus, and their evolution and relationships. In this study we used molecular data, the nucleotide sequences of four protein-coding mitochondrial genes (3806 bp total), to provide a well-supported phylogeny for the genus Natrix . With these molecular data, evidence from the fossil record, and knowledge of palaeogeological events, we used two approaches in designing a time scale which we used to date the major events in Natrix speciation and intraspecific variation. Our data strongly support a phylogeny for the genus in which N. maura is basal with N. natrix and N. tessellata being sister species. The calibrated molecular clock suggests that N. maura diverged from the common ancestor of the three species 18–27 mya and that N. natrix and N. tessellata diverged 13–22 mya. Although the ranges of these estimates are large they support an early Miocene to late Oligocene origin for the three species. Intraspecific divergence is estimated to have commenced 5.3, 6.0 and 6.7 mya with evolutionary rates of 1 : 1.25 : 1.35% per million years for N. maura, N. natrix and N. tessellata , respectively.  © 2006 The Linnean Society of London, Biological Journal of the Linnean Society , 2006, 87 , 127–143.  相似文献   

4.
The Opegrapha species with 3-septate ascospores growing on Pertusaria and Ochrolechia are revised. Two species are recognized: Opegrapha anomea (of which O. pertusariae , O. quaternella , O. wetmorei and possibly Leciographa weissii are considered to be synonyms), and O. blakii Ertz & Diederich sp. nov. described from a sterile lichen with an Ochrolechia -like thallus, known from Ecuador and Venezuela. Opegrapha anomea and several related lichenicolous species with roundish or irregular, often multilocular ascomata are morphologically intermediate between Opegrapha and Plectocarpon , and might represent a distinct genus.  © 2004 The Linnean Society of London, Botanical Journal of the Linnean Society , 2004, 144, 235−241.  相似文献   

5.
Shrimps from the genus Lysmata are known because of their wide diversity of lifestyles, mating systems, symbiotic partnerships, and conspicuous coloration. They can occur in crowds (large aggregations), in small groups, or as socially monogamous pairs. Shrimps from this genus are rare, if not unique among crustaceans, because of their unusual sexual system. To date, the sexual system of all species investigated comprises a protandric simultaneous hermaphroditism: shrimps initially mature and reproduce as males and later in life turn into functional simultaneous hermaphrodites. The evolutionary relationships of the species within the genus are unsettled. A molecular phylogeny of the group may shed light on the evolutionary origins of the peculiar sexual and social systems of these shrimps and help resolve standing taxonomic questions long overdue. Using a 647-bp alignment of the 16S rRNA mitochondrial DNA, we examined the phylogenetic relationship of 21 species of shrimps from the genus Lysmata from several biogeographical regions; the Atlantic, Pacific, and Indo-Pacific. The resulting phylogeny indicates that the genus is paraphyletic and includes the genus Exhippolysmata . The constituent species are subdivided into three well supported clades: one group exclusively composed of neotropical species; a second clade comprising the Indo-Pacific and Atlantic symbiotic fish cleaner shrimps; and a third clade including tropical and temperate species from the Atlantic and Pacific. The molecular phylogeny presented here does not support a historical contingency hypothesis, previously proposed to explain the origins of protandric simultaneous hermaphroditism within the genus. Furthermore, the present study shows that monogamous pair-living is restricted to one monophyletic group of shrimps and therefore probably evolved only once.  © 2009 The Linnean Society of London, Biological Journal of the Linnean Society , 2009, 96 , 415–424.  相似文献   

6.
Although the integration of DNA information in taxonomy has been invaluable, logistical problems relating to sampling can seriously limit its applicability. Here we describe the analysis of a morphologically cryptic species complex, in which we maximize the information present by using both a DNA phylogeny and a multivariate morphometric approach. The green pitviper Trimeresurus stejnegeri s.l. is widespread in Asia, with a number of described subspecies (some of which are considered full species by some workers) and two new species that have recently been described from Thailand. The phylogeny indicates three clades, which can also be discerned in the principal component analyses of morphological variation. Combining molecular and morphological information permits evaluation of the taxonomic position of populations not represented in the phylogeny − in particular, the subspecies T. s. chenbihui and T. s. yunnanensis . We discuss nomenclatural issues raised by this analysis, although these cannot be fully resolved until the holotypes of these subspecies can be examined. Finally, we apply a molecular clock calibrated in New World pitvipers, and discuss some of the palaeoclimatic changes that might have impacted upon diversification in this group.  © 2004 The Linnean Society of London, Biological Journal of the Linnean Society, 2004, 82 , 219–235.  相似文献   

7.
A new species, Epipactis duriensis Bernardos, D. Tyteca, Revuelta & Amich is described and illustrated from north-east Portugal. Notes on its distribution, ecology, karyology, micromorphology and taxonomic relationships are presented as well as molecular data based on ITS analysis. A list of diagnostic differences between E. duriensis and the closely related species E. lusitanica and E. tremolsii is provided.  © 2004 The Linnean Society of London, Botanical Journal of the Linnean Society , 2004, 145 , 239–249.  相似文献   

8.
Two new species of the genus Galium are described from the Iberian Peninsula: G. moralesianum Ortega-Olivencia & Devesa, and G. talaveranum Ortega-Olivencia & Devesa. The first grows on limestone or dolomitic-limestone outcrops in south-east Spain (the Segura and Gádor mountain ranges) and shows morphological similarities with G. boissieranum Ehrend. & Krendl, which is endemic to southern Spain (mountains of Málaga). The second inhabits the margins of water courses, alder stands and cork-oak dehesas (parkland-type systems) of the west of the Iberian Peninsula, and is morphologically reminiscent of G. mollugo L. The chromosome numbers of these two species and of G. boissieranum are given.  © 2003 The Linnean Society of London, Botanical Journal of the Linnean Society , 2003, 143 , 177−187.  相似文献   

9.
The genus Portunus encompasses a comparatively large number of species distributed worldwide in temperate to tropical waters. Although much has been reported about the biology of selected species, taxonomic identification of several species is problematic on the basis of strictly adult morphology. Relationships among species of the genus are also poorly understood, and systematic review of the group is long overdue. Prior to the present study, there had been no comprehensive attempt to resolve taxonomic questions or determine evolutionary relationships within this genus on the basis of molecular genetics. Phylogenetic relationships among 14 putative species of Portunus from the Gulf of Mexico and other waters of the western Atlantic were examined using 16S sequences of the rRNA gene. The resultant molecularly based phylogeny disagrees in several respects with current morphologically based classification of Portunus from this geographical region. Of the 14 species generally recognized, only 12 appear to be valid. We recommend that P. vossi be hereafter regarded as a junior synonym of P. spinimanus and that P. bahamensis be regarded as a junior synonym of P. depressifrons . Our analysis suggests that western Atlantic members of the genus can be subdivided into at least three well-defined clades. Pending further molecular analyses with a large subset of species, it appears that the genus is not monophyletic and that it warrants further taxonomic revision.  © 2007 The Linnean Society of London, Zoological Journal of the Linnean Society , 2007, 150 , 211–220.  相似文献   

10.
Seed dormancy in relation to seed storage behaviour in Acer   总被引:3,自引:0,他引:3  
Dormancy in seeds of Acer opalus is shown to be mainly caused by the seed coats, although a slight embryo dormancy exists in fresh seeds. The ability to germinate after drying indicates that seed storage behaviour is orthodox. Recalcitrant seeds were heavier than orthodox seeds not only within section Acer but also within the whole genus after statistical control of phylogeny, through a phylogenetic ANOVA with data from two different Acer phylogenies. An evolutionary change from orthodox to recalcitrant behaviour is postulated for genus Acer , but this change appears not to have been accompanied by a change in seed dormancy, at least in the taxonomic section in which Acer opalus belongs.  © 2004 The Linnean Society of London, Botanical Journal of the Linnean Society , 2004, 145 , 203–208.  相似文献   

11.
Tragopogon cazorlanum (Asteraceae: Lactuceae) is proposed as a new Spanish species with distribution restricted to the Baetic mountains (south-eastern Spain). Its morphological, palynological, chromosomal, biogeographical and ecological features are discussed, as well as its main relationships and differences with reference to other Spanish species of the genus.  © 2004 The Linnean Society of London, Botanical Journal of the Linnean Society , 2004, 146 , 505–511.  相似文献   

12.
East Africa has a reduced mangrove crab species richness when compared to Asian mangroves. To date, only one species of Perisesarma de Man, 1895 has been reported in East Africa, despite more than 30 years of mangrove research in this region. Based on morphology, colour, mtDNA and behaviour, we describe a new species of Perisesarma from Kenya, P. samawati sp. nov. Surprisingly, when comparing molecular data from other species within this genus, P. samawati sp. nov. and the sympatric P. guttatum (A. Milne Edwards, 1869) are not sister species. Some aspects of the ecology of P. guttatum and P. samawati sp. nov. are compared and the differences discussed. Additionally, we compare P. samawati sp. nov. with the ecological literature of a possible sister species P. eumolpe de Man, 1895 from Malaysian mangroves. Our findings suggest that the new species is an ecologically important species in East African mangroves.  © 2004 The Linnean Society of London, Zoological Journal of the Linnean Society , 2004, 141 , 435–445.  相似文献   

13.
Species-level phylogeny of the Butterfly tribe Argynnini is established based on 141 characters derived from wing and genitalia morphology of both sexes. The Argynnini can be divided into three subtribes; Yrameina comprising Yramea and Boloria s . l ., Argynnina comprising Prokuekenthaliella , Issoria , Brenthis , and all the 'large fritillary' species joined in the genus Argynnis s . l . and a new subtribe Euptoietina comprising only the genus Euptoieta . The classical genus Issoria s . l . is polyphyletic regarding Yramea and possibly paraphyletic regarding the two Afrotropic species baumanni and hanningtoni ; these two species are tentatively transferred to the old genus/subgenus Prokuekenthaliella . Surprisingly, one Afrotropic species, Issoria smaragdifera is closely related to the East Palaearctic Issoria species. A revised classification of Argynnini is proposed based on the obtained phylogeny. Studies of larval host plants based on the obtained phylogeny suggest that the ancestral Argynnini used Passiflora and Violaceae, but already the ancestor of Yrameina + Argynnina was probably specialized on Violaceae. Whereas the Boloria species have turned to other food plants such as Dryas , Vaccinium and Salix on several occasions, only Brenthis among the Argynnina use other host plants than Viola (mainly Rosaceae). The habit of laying eggs away from the food plant has probably evolved twice within Argynnina.  © 2006 The Linnean Society of London, Biological Journal of the Linnean Society , 2006, 89 , 627–673.  相似文献   

14.
The genus Prosopis is an important member of arid and semiarid environments around the world. To study Prosopis diversification and evolution, a combined approach including molecular phylogeny, molecular dating, and character optimization analysis was applied. Phylogenetic relationships were inferred from five different molecular markers ( mat K- trn K, trn L- trn F, trn S- psb C, G3pdh, NIA). Taxon sampling involved a total of 30 Prosopis species that represented all Sections and Series and the complete geographical range of the genus. The results suggest that Prosopis is not a natural group. Molecular dating analysis indicates that the divergence between Section Strombocarpa and Section Algarobia plus Section Monilicarpa occurred in the Oligocene, contrasting with a much recent diversification (Late Miocene) within each of these groups. The diversification of the group formed by species of Series Chilenses, Pallidae, and Ruscifoliae is inferred to have started in the Pliocene, showing a high diversification rate. The moment of diversification within the major lineages of American species of Prosopis is coincident with the spreading of arid areas in the Americas, suggesting a climatic control for diversification of the group. Optimization of habitat parameters suggests an ancient occupation of arid environments by Prosopis species.  © 2008 The Linnean Society of London, Biological Journal of the Linnean Society , 2008, 93 , 621–640.  相似文献   

15.
Terrestricythere elisabethae sp. nov. is described from a semiterrestrial coastal habitat at two sites in Hampshire, southern England. It is the first record of a living population of the genus outside the Far East (north-west Pacific). Based on extensive collections and from observations of cultures, its morphology is described (including a formal definition of the unique 'visordont' hinge), as well as its ontogeny and lifestyle (encompassing habitat, life cycle, mode of life and locomotion). A further new species from Somerset, south-west England is also recorded on the basis of a single specimen but left in open nomenclature. The affinities of the Terrestricytheroidea are discussed in the context of a tentative phylogeny of podocopan Ostracoda. Both carapace and appendage characters are such as to warrant maintaining it as a separate superfamily, which is more closely related to the Cytheroidea and Darwinuloidea than to the Cypridoidea.  © 2004 The Linnean Society of London, Zoological Journal of the Linnean Society , 2004, 142 , 253–288.  相似文献   

16.
We describe the larval stages of three species of the Asian-African tiger frogs Hoplobatrachus chinensis, H. occipitalis and H. tigerinus . The tadpoles of all three species are very similar, with peculiar oral features: (1) double rows of needle-like labial teeth, (2) strong emarginations on the large jaw sheaths and (3) keratinized spurs on the buccal floor. Characters 1 and 2 (and perhaps 3) are probably related to the carnivorous habits of these tadpoles. A molecular phylogeny based on 2430 base pairs of two nuclear and four mitochondrial genes corroborated monophyly of Asian and African Hoplobatrachus, and identified Euphlyctis as their sister group. Tadpoles of the latter genus lack buccal spurs and double labial tooth rows but share large jaw sheaths, the upper with a medial projection. Therefore, the common ancestor of Euphlyctis and Hoplobatrachus probably was also characterized by this state, and may have been facultatively carnivorous. Further carnivorous specializations in Hoplobatrachus could explain why tiger frogs have been so successful in populating arid environments where ponds are at high risk of desiccation. Larval morphology may prove to be the key innovation which enabled them to disperse, in the Late Cenozoic, into their current very wide distribution area in Asia and Africa.  © 2004 The Linnean Society of London, Biological Journal of the Linnean Society , 2004, 81 , 171–181.  相似文献   

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A mass return to land of the megalop of the land crab Gecarcinus ruricola is reported. The return occurred in June 2004 on the island of Providencia in the western Caribbean: this is the first detailed report of larval return in this species, and the most detailed report for any gecarcinid. Crabs emerged from the sea as megalops over 2 to 3 days, and moved rapidly landwards. Vast numbers migrated > 50 m across land before moulting to the first crab – the megalop is clearly the invasive stage. The megalop is described for the first time, and criteria are identified to discriminate it from other Caribbean gecarcinids.  © 2006 The Linnean Society of London, Zoological Journal of the Linnean Society , 2006, 146 , 149–164.  相似文献   

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Cytological studies were carried out on 14 taxa belonging to Amitostigma , Chusua , Galearis , Habenaria , Hemipilia , Hemipiliopsis , Herminium , Peristylus and Ponerochis , collected mostly from the south-eastern part of the Hengduan Mountain Region, south-west China. Cytological data on 11 of the taxa are reported for the first time. The interphase nuclei were either of the simple chromocentre type or intermediate between simple and complex chromocentre types. The nuclear morphology of Hemipiliopsis at interphase supports the conclusion that it is related more closely to Chusua and Ponerochis than to Habenaria . At the whole tribe level, however, the results did not indicate a clear correlation between morphological features of the interphase nuclei and phylogeny. The somatic chromosome numbers were 2 n  = 42 in ten species and 2 n  = 32, 38, 40, 64 and 72 in four species. The chromosome counts of 2 n  = 32 and 64 in Habenaria aitchsonii are rare in the genus. It is proposed that the repeated change of chromosome number from x  = 7 to x  = 8 has played an important role in the evolution of the tribe Orchideae. This change has occurred mainly in the European subtribe Orchidinae, but also in the Asian subtribe Habenariinae.  © 2004 The Linnean Society of London, Botanical Journal of the Linnean Society , 2004, 145 , 231–238.  相似文献   

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