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1.
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   

2.
A morphological and taxonomical account of the taxon Rogneda is given. A new interpretation of the stylet morphology is presented and a new terminology pertaining to these hard parts is proposed. All known species are discussed and additional information is provided when necessary. Seven new species are described. Five of these are from the Mediterranean: R. colpaerti sp. nov. , R. licyae sp. nov. , R. schaereri sp. nov. , R. valckei sp. nov. and R. vangronsveldi sp. nov . R. verveckeni sp. nov . is from the Atlantic coast of Spain (Galicia). The seventh, R. martensi sp. nov. , is from Indonesia and is the first species of Rogneda to be found outside the Northeast Atlantic and the Mediterranean. All new species can be recognized based on the morphology of the stylets in the male system. A discussion on the similarities and differences of the 22 species is provided, resulting in the grouping of the species into seven morphological groups: the capulata -group, the falcata -group, the hibernica -group, the polyrhabdota -group, the steueri -group, the tripalmata -group and the westbladi -group. R. minuta cannot be placed into any of these groups and therefore stands alone within the taxon. An identification key is provided to facilitate further study of the taxon Rogneda .  © 2008 The Linnean Society of London, Zoological Journal of the Linnean Society , 2008, 153 , 1–28.  相似文献   

3.
The taxonomy of rain forest species of the genus Chlorophytum in central and west Africa has to date been difficult to resolve. Plants collected in the Guineo-Congolean plant geographical region deposited in several herbaria formed the basis for a morphometric analysis using Principal Component Analyses and including 16 characters. In total, 166 individuals were included from 461 herbarium collections, from which 57 seeds were scanned to investigate the surface structures. Eight species are recognized, including one with three subspecies and another with three varieties. Four new combinations are proposed ( Chlorophytum comosum (Thunb.) Jacques var. bipindense (Engl. & K. Krause) A.D. Poulsen & Nordal, C. comosum (Thunb.) Jacques var. sparsiflorum (Baker) A.D. Poulsen & Nordal, C. lancifolium Baker ssp. cordatum (Engl.) A.D. Poulsen & Nordal, and C. lancifolium Baker ssp. togoense (Engl.) A.D. Poulsen & Nordal), ten new synonyms are introduced and three lectotypes are designated.  © 2005 The Linnean Society of London, Botanical Journal of the Linnean Society , 2005, 148 , 1–20.  相似文献   

4.
The taxonomy of the New World species of the genus Trichadenotecnum is revised. A total of 44 species, including 29 new species, were treated. These species are classified into 12 monophyletic species groups, eight of them newly proposed here. Two species previously assigned to Trichadenotecnum , T. pichincha New & Thornton and T. sylvaticum Turner, are recognized as not belonging to this genus. Phylogenetic relationships among 16 previously and presently proposed species groups are estimated based on a data matrix of 58 morphological characters. Trees from these analyses support monophyly of Trichadenotecnum and the proposed species groups. The New World species were divided into three major clades. Based on the phylogenetic hypothesis and distributional pattern of the species groups, the biogeographical history of the New World Trichadenotecnum is discussed.  © 2008 The Linnean Society of London, Zoological Journal of the Linnean Society , 2008, 153 , 651–723.  相似文献   

5.
Paeonia (Paeoniaceae) in the Caucasus   总被引:1,自引:0,他引:1  
The taxonomy of the genus Paeonia in the Caucasus has been controversial, with recognized species varying in number from one to 13. The taxonomic history of Paeonia in this area is reviewed (including an analysis of the characters used by previous authors) based on extensive field observations, population sampling and critical examination of a large number of herbarium specimens. The results show that Paeonia may be divided into three groups. The P. intermedia group is known from only a single population. In the P. tenuifolia group, all the characters used for distinguishing the three previously recognized species were found to be polymorphic. In the P. daurica group, petal colour, shape and size of leaflets, and indumentum of leaflets and carpels were used to distinguish nine species, but these characters were found to be polymorphic or continuous in variation, and thus can only be used for infraspecific classification. Thus, three species are recognized: P. intermedia , P. tenuifolia and P. daurica . The last species is further divided into five subspecies: sspp. coriifolia , wittmanniana , mlokosewitschii , macrophylla and tomentosa stat. nov .  © 2003 The Linnean Society of London, Botanical Journal of the Linnean Society, 2003, 143 , 135–150.  相似文献   

6.
Stomion is one of three speciose and taxonomically difficult genera of flightless Darwin's darkling beetles of the Galápagos Islands. The previously named species and subspecies of Stomion are analysed by morphometric and cladistic methods. Eleven species are here recognized, which probably descended from colonization by a single ancestral species. Cladistic analysis yielded two weakly supported clades that are different from previously published morphological and allozyme genotype groups. Phenotypic and genotypic characters may be evolving independently. There is much within-species variation, but there is no compelling evidence of adaptive radiation in Stomion , in contrast to that in the famous Darwin's finches. The analyses show the need for changes in morpho-species taxonomy: S. punctipennis Van Dyke ( syn. nov. ) is elevated to full species from a subspecies of S. galapagoensis Waterhouse. There is no evidence to support the validity of: S. laevigatum santacruzensi Franz ( syn. nov. ), synonomized here under S. l. laevigatum Waterhouse; S. galapagoensis leleupi Kaszab ( syn. nov. ), synonomized here under S. linelli Blair; S. galapagoensis pinzoni Franz ( syn. nov. ), synonomized here under S. obesum Van Dyke. S. genovesa sp. nov. is described from Genovesa Island. Lectotypes are designated for S. galapagoensis Waterhouse, S. laevigatum Waterhouse and S. helopoides Waterhouse .   © 2004 The Linnean Society of London, Zoological Journal of the Linnean Society , 2004, 141 , 135–152.  相似文献   

7.
Integrative taxonomy considers species boundaries from multiple, complementary perspectives, with the main objective being to compare the observed data against the predictions of the methodologies used. In the present study we used three methods for delineating species boundaries within the cosmopolitan nematode species Rhabditis ( Pellioditis ) marina and Halomonhystera disjuncta . First, phylogenetic relationships among molecular sequences from the mitochondrial cytochrome oxidase c subunit 1 gene (COI), and from two nuclear regions, internal transcribed spacer (ITS) and D2D3, were analysed. Subsequently, multivariate morphometric analysis was used to investigate whether concordant molecular lineages were also morphologically distinct. When morphological differences were found, typological taxonomy was performed to identify fixed or non-overlapping characters between lineages. Interbreeding experiments were conducted between the two closest related lineages of R . ( P. ) marina to investigate potential reproductive isolation. This integrative approach confirmed the presence of several species within each nominal species: molecular lineages were concordant across two independent loci (COI and ITS), and were characterized by significant morphological divergence. Most lineages were also detectable in the D2D3 region, but were less resolved. The two lineages investigated in our study did not produce offspring. Our results highlight that classical taxonomy grossly underestimates species diversity within the phylum Nematoda.  © 2008 The Linnean Society of London, Biological Journal of the Linnean Society , 2008, 94 , 737–753.  相似文献   

8.
The polytypic Cretan land snail Albinaria hippolyti has a range that is partly fragmented and partly subdivided by hybrid zones. For this reason, it has served as a model species for investigating speciation and radiation in Mediterranean Clausiliidae. The first internal transcribed spacer ( ITS-1 ) of the nuclear ribosomal DNA was sequenced in 20 populations of A. hippolyti and phylogenetically analysed using maximum parsimony. We employed a novel method involving logarithmic weighting of gaps and topological constraints based on bootstrap values. The resulting phylogeography suggests that the species has undergone a recent cycle of range expansion and range reduction. Speciation cannot be linked to major geological vicariance events in the Miocene and Pliocene, as has been suggested previously. The subspecies A. h. arthuriana appears unrelated to other A. hippolyti subspecies, which supports recent suggestions, based on morphology, to regard it as a separate species.  © 2004 The Linnean Society of London, Biological Journal of the Linnean Society , 2004, 83 , 317–326.  相似文献   

9.
10.
The classification of the Neotropical genera of the Ennominae is reviewed and 267 genera are recognised to occur in this region. Three new genera are described and three others are reinstated, while 48 generic synonyms are newly established. Other changes established in this work include 14 species synonyms and 237 new or reinstated combinations. External features and genitalia of representative members of the genera are illustrated (753 figures). All the known Neotropical species and subspecies of Ennominae are listed ( c . 3470), plus their synonyms. The tribes to which the genera belong are assessed, with c . 200 of the genera assigned to tribe or other suprageneric grouping.  © 2002 The Linnean Society of London, Zoological Journal of the Linnean Society , 2002, 135 , 121–401.  相似文献   

11.
12.
The high-ploid species Papaver dahlianum , P. lapponicum , P. laestadianum and P. radicatum were compared by means of enzyme electrophoresis. The diploid P. alpinum from the Alps and garden material of the assumed diploid P. croceum from Asia were also included. The results are compared with those of previous morphological and cytological investigations. Generally, only small differences were found among the species. The maintenance of 13 subspecies of P. radicatum as published from the Nordic area was not supported. The octoploid P. laestadianum was nearly identical to the decaploid P. radicatum and inclusion in P. radicatum is justified. The octoploid P. lapponicum was also very similar to P. radicatum and inclusion of it in the latter should be considered. The most distinct of the taxa was the decaploid P. dahlianum , and the maintenance of two subspecies, ssp. polare and ssp. dahlianum can be defended. A hybrid origin of P. radicatum (10x) from P. lapponicum (8x) and P. alpinum (2x), and of P. dahlianum (10x) from P. lapponicum and P. croceum (2x) has been proposed, but a more likely explanation might be that P. dahlianum , P. radicatum and P. lapponicum have all arisen by polyploidization from closely related diploids without hybridization.  © 2003 The Linnean Society of London, Botanical Journal of the Linnean Society , 2003, 143 , 255−269.  相似文献   

13.
The classification of the genera of the widely distributed Old World tribe Pseudoterpnini is reviewed and 34 genera are recognized. Two new generic synonyms ( Sterictopsis Warren and Oxyphanes Turner as synonyms of Rhuma Walker), and 21 new or reinstated combinations are established. Representative moths of all the genera are illustrated in colour (upper side and underside), and genitalia of all genera are illustrated in monochrome (162 figures). All the known species and subspecies of Pseudoterpnini are listed (321), together with their synonyms. The Pseudoterpnini and their characters are assessed, and many genera are newly assigned to the tribe.  © 2007 Natural History Museum, London. Journal compilation © 2007 The Linnean Society of London, Zoological Journal of the Linnean Society , 2007, 150 , 343–412.  相似文献   

14.
Miniopterus schreibersii is a polytypic bat species, with one of the widest distribution ranges among the mammals. We studied the genetic differentiation and taxonomy of this species in the transition zone between south-eastern Europe and Anatolia (in Asia), where two subspecies have been described. The results indicated a sharp genetic break between the samples from western Anatolia and south-eastern Europe and those of eastern Anatolia. In addition, the samples from western Anatolia and south-eastern Europe were seen to be reciprocally monophyletic, although the differentiation was less drastic. These patterns of genetic differentiation suggest the presence of two distinct groups within the M. schreibersii complex in the region, concordant with previous subspecific recognition. The cause of this genetic break is most likely differentiation in separate glacial refugia followed by secondary contact. However, more samples are needed to assess whether these represent different species, as well as to understand more clearly the causes of this differentiation.  © 2006 The Linnean Society of London, Biological Journal of the Linnean Society , 2006, 87 , 577–582.  相似文献   

15.
Isoetes velata A. Braun is an amphibious plant with Mediterranean and Ibero-Atlantic distribution, showing marked morphological variability. Within the same geographical area, closely related restricted-range taxa are also present, including I. velata ssp. asturicense (restricted to mountainous areas of the north-west Iberian Peninsula) and I. boryana (restricted to the southern French Atlantic coast). These related taxa have unclear taxonomy and are both threatened. We performed a morphometric study of specimens of the three taxa. Our results suggest that I. velata ssp. asturicense is better considered as a distinct species, I. asturicense Laínz (Laínz), distinguishable from the other two taxa by mean megaspore length ( N  ≥ 30) < 360 µm. In contrast, our results do not support consideration of I. boryana as a separate species, and we here propose that this taxon be considered as a variety, I. velata A. Braun var. boryana M.I. Romero & C. Real stat. nov.   © 2005 The Linnean Society of London, Botanical Journal of the Linnean Society , 2005, 148 , 459–464.  相似文献   

16.
The systematics of the Asplenium seelosii complex has been debated for a long time. This complex includes strictly rupicolous plants that live on limestone cliffs mainly in the mountains of south-west Europe: the Alps, the Pyrenees, and several mountain ranges of the eastern Iberian Peninsula. The disjunct distribution of its populations and several morphological characters, i.e. leaf indumentum and the structure of the perispore, have been used to distinguish two species and up to four subspecies. The goal of this study was to determine whether the characters of the gametophytic generation and young sporophytes can contribute to the recognition of the proposed taxa. The analysis of all of these characters together differentiated two groups that correspond to the established species, A. seelosii and A. celtibericum , but not enough differences were found to separate the subspecies in each of them.  © 2006 The Linnean Society of London, Botanical Journal of the Linnean Society , 2006, 151 , 375–386.  相似文献   

17.
18.
A Baltic amber inclusion of a fossil spruce seedling of which the lower part of the hypocotyl and the primary root are not preserved is provisionally described as Picea baltica ad int. The remnant of the hypocotyl and the basal parts of the cotyledons are infested by a conidial fungus. Its conidiophores correspond to those of the genus Gonatobotryum Corda. However, the fungus is not assignable to any extant species and is therefore described as a new species, Gonatobotryum piceae . A further infestation, most probably by a stroma-forming anamorph, is visible on the cotyledons of the seedling. Its mode of infestation is similar to that of Sirococcus strobilinus Preuss which occurs in extant spruce seedlings.  © 2007 The Linnean Society of London, Botanical Journal of the Linnean Society , 2007, 155 , 449–456.  相似文献   

19.
Using independently segregating nuclear single nucleotide polymorphisms (SNPs) and mitochondrial control region sequences, we found an east–west division among sampled willow grouse Lagopus lagopus subspecies. This division cut across the range of the subspecies with the largest distribution (lagopus) and thus contradicted existing taxonomic classifications. Russian Lagopus lagopus lagopus tended to cluster with North American willow grouse partly classified as other subspecies. Scandinavian willow grouse (L. l. lagopus) clustered with red grouse from Britain and Ireland (Lagopus lagopus scoticus and Lagopus lagopus hibernicus) but substructuring confirmed the monophyly of the latter. In North America, we could not detect any major genetic divisions apart from two birds described as alexandrae from the Heceta Island (Alaska) when using mitochondrial sequences. Other samples from North America were intermingled regardless of whether they were described as muriei, alexandrae or lagopus. A specimen described as alexandrae was to some extent distinct when analysing the SNP data. The genetic analyses indicated some concordance between genetics and taxonomy but not complete congruence. This is particularly evident for mitochondrial DNA network analyses. We suggest that the taxonomy of this species would benefit by a careful re‐examination of the available evidence for subspecies. It appears as if subspecies status is a poor proxy for assigning evolutionary significant units and management units in this species. © 2013 The Linnean Society of London, Biological Journal of the Linnean Society, 2013, 110 , 77–90.  相似文献   

20.
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