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1.
Using different data sets mainly from the plant family Rubiaceae, but in parts also from the Apocynaceae, Asteraceae, Lardizabalaceae, Saxifragaceae, and Solanaceae, we have investigated the effect of number of characters, number of taxa, and kind of data on bootstrap values within phylogenetic trees. The percentage of supported nodes within a tree is positively correlated with the number of characters, and negatively correlated with the number of taxa. The morphological analyses are based on few characters and weakly supported trees are expected. The percentage of supported nodes is also dependent on the kind of data analyzed. In analyses of Rubiaceae based on the same number of characters, RFLP data give trees with higher percentage of supported nodes than rbcL and morphological data. We also discuss the support values for particular nodes at the familial and subfamilial levels. Two new data sets of ndhF and rbcL sequences of Rubiaceae are analyzed and together with earlier studies of the family we can conclude that the monophyly of the Rubiaceae is supported and within the family there are three well supported, but not easily characterized, large subfamilies, Rubioideae, Cinchonoideae s.s. and Ixoroideae s.l. There are also a few genera (Luculia and Coptosapelta) unclassified to subfamily.  相似文献   

2.
Nucleotide and inferred amino acid sequences from two nuclear protein-encoding genes, elongation factor-aα and RNA polymerase II, were obtained from 34 myriapods and 14 other arthropods to determine phylogenetic relationships among and within the myriapod classes. Phylogenetic analyses using maximum parsimony and maximum likelihood methods recovered all three represented myriapod classes (Chilopoda, Diplopoda, Symphyla) and all multiply sampled chilopod and diplopod orders, often with high node support. In contrast, relationships between classes and between orders were recovered less consistently and node support was typically lower. The temporal structure of phylogenetic diversification in Myriapoda may explain this apparent pattern of the phylogenetic recovery.  相似文献   

3.
Partial DNA sequences from two mitochondrial (mt) and one nuclear gene (cytochrome b, 12S rRNA, and C-mos) were used to estimate the phylogenetic relationships among the six extant species of skinks endemic to the Cape Verde Archipelago. The species form a monophyletic unit, indicating a single colonization of the islands, probably from West Africa. Mabuya vaillanti and M. delalandii are sister taxa, as indicated by morphological characters. Mabuya fogoensis and M. stangeri are closely related, but the former is probably paraphyletic. Mabuya spinalis and M. salensis are also probably paraphyletic. Within species, samples from separate islands always form monophyletic groups. Some colonization events can be hypothesized, which are in line with the age of the islands. C-mos variation is concordant with the topology derived from mtDNA.  相似文献   

4.
Major progress has been made recently toward resolving the phylogeny of Noctuoidea, the largest superfamily of Lepidoptera. However, numerous questions and weakly supported nodes remain. In this paper we independently check and extend the main findings of multiple recent authors by performing maximum‐likelihood analyses of 5–19 genes (6.7–18.6 kb) in 74 noctuoids representing all the families and a majority of the subfamilies. Our results strongly support the six family system of Zahiri et al., with the former Lymantriidae and Arctiidae subsumed within the huge family Erebidae, and Noctuidae restricted largely to the subfamilies with so‐called trifine hindwing venation. Our data also strongly corroborate monophyly of the set of four families with quadrifid forewing venation, to the exclusion of Notodontidae, and removal from the latter of Oenosandridae. Other among‐family relationships, however, remain unsettled. Our evidence is equivocal on the position of Oenosandridae, which are sister group to either Notodontidae alone or to all other noctuoids. Like other recent nuclear gene studies, our results also provide no strong support for relationships among the four quadrifid forewing families. In contrast, within families our analyses significantly expand the list of robustly resolved relationships, while introducing no strong conflicts with previous molecular studies. Within Notodontidae, for which we present the largest molecular taxon sample to date, we find strong evidence for polyphyly for some, or all, recent definitions of the subfamilies Thaumetopoeinae, Pygaerinae, Notodontinae and Heterocampinae. Deeper divergences are incompletely resolved but there is strong support for multiple ‘backbone’ nodes subtending most of the subfamilies studied. Within Erebidae, we find much agreement and no strong conflict with a recent previous study regarding relationships among subfamilies, and somewhat stronger support. Although many questions remain, the two studies together firmly resolve positions for over half the subfamilies. Within Noctuidae, we find no strong conflict with previous molecular studies regarding relationships among subfamilies, but much stronger resolution along the ‘backbone’ of the phylogeny. Combining information from multiple studies yields strongly resolved positions for most of the subfamilies. Finally, our results strongly suggest that the tribes Pseudeustrotiini and Prodeniini, currently assigned to the largest subfamily, Noctuinae, do not belong there. In sum, our results provide additional corroboration for the main outlines of family‐level phylogeny in Noctuoidea, and contribute toward resolving relationships within families.  相似文献   

5.
Analyses of living and fossil taxa are crucial for understanding biodiversity through time. The total evidence method allows living and fossil taxa to be combined in phylogenies, using molecular data for living taxa and morphological data for living and fossil taxa. With this method, substantial overlap of coded anatomical characters among living and fossil taxa is vital for accurately inferring topology. However, although molecular data for living species are widely available, scientists generating morphological data mainly focus on fossils. Therefore, there are fewer coded anatomical characters in living taxa, even in well-studied groups such as mammals. We investigated the number of coded anatomical characters available in phylogenetic matrices for living mammals and how these were phylogenetically distributed across orders. Eleven of 28 mammalian orders have less than 25% species with available characters; this has implications for the accurate placement of fossils, although the issue is less pronounced at higher taxonomic levels. In most orders, species with available characters are randomly distributed across the phylogeny, which may reduce the impact of the problem. We suggest that increased morphological data collection efforts for living taxa are needed to produce accurate total evidence phylogenies.  相似文献   

6.
7.
We present a molecular systematic investigation of relationships among family-group taxa of Membracidae, comprising nearly 3.5 kb of nucleotide sequence data from the nuclear genes elongation factor-1alpha (EF-1alpha: 958 bp) and 28S ribosomal DNA (28S rDNA: 2363 bp); data partitions are analyzed separately and in combination for 79 taxa. Analysis of the combined sequence data provided a better-resolved and more robust hypothesis of membracid phylogeny than did separate analyses of the individual genes. Results support the monophyly of the family Membracidae and indicate the presence of two major lineages (Centrotinae + Stegaspidinae + Centrodontinae and Darninae + Membracinae + Smiliinae). Within Membracidae, molecular data support the following assertions: (1) the previously unplaced genera Antillotolania and Deiroderes form a monophyletic group with Microcentrini; (2) Centrodontini and Nessorhinini are monophyletic clades that arise independently from within the Centrotinae; (3) Centrotinae is paraphyletic with respect to Centrodontinae; (4) the subfamily Membracinae is monophyletic and possibly allied with the darnine tribe Cymbomorphini; (5) the subfamily Darninae is paraphyletic; (6) the subfamily Smiliinae is paraphyletic, with molecular evidence indicating the exclusion of Micrutalini and perhaps Acutalini and Ceresini; and (7) Membracidae arose and diversified in the New World with multiple subsequent colonizations of the Old World. Our phylogenetic results suggest that morphology-based classifications of the Membracidae need to be reevaluated in light of emerging molecular evidence.  相似文献   

8.
Lafontaine JD  Schmidt BC 《ZooKeys》2011,(149):145-161
A total of 115 additions and corrections are listed and discussed for the check list of the Noctuoidea of North America north of Mexico published in 2010. Thirty-two of these are changes in authorship and/or date of publication or spelling. Taxonomic changes are 33 new or revised synonymies, three new combinations, and six revisions in status from synonymy to valid species.  相似文献   

9.
The use of single copy nuclear markers is of increasing importance in plant phylogenetics. The generally higher level of variability compared to chloroplast DNA and the ability to use incongruence in a multilocus analysis to determine reticulation patterns makes these kinds of sequence based markers especially useful for species level investigations. However, the prevalence of gene duplication that results from the high frequency of polyploidization events during the evolution of higher plants can impede marker development especially for groups lacking model organisms. Here, we present the strategy and results of marker development for phylogenetic analysis in Micromeria, using publicly available DNA sequences and ESTs from related genera from Lamiaceae, subfamily Nepetoideae. By eliminating markers with signatures of duplication during four steps of marker development, we were able to select 19 primer pairs that resulted in orthologous products for all the species studied. This corresponds to 23% of the initial 84 primer pairs designed. Using an initial sampling of eight individuals, we tested the markers for support of phylogenetic hypotheses related to the evolution of Micromeria on the Canary Islands. While some hypotheses were supported by all markers, an east west split, with a closer relationship between the species of Tenerife and Madeira on one hand and the ones from Gran Canaria and the eastern islands on the other is supported by 12 markers but contradicted by the remaining seven. This indicates that reticulation and inter-island gene flow played a role in the evolution of Micromeria.  相似文献   

10.
The lice, Haffneria grandis and Saemundssonia were extracted from their hosts, skuas (Aves: Stercorariidae). Lice were extracted from dead birds by combing feathers, while lice from live birds were extracted using a delousing chamber containing chloroform vapour. Lice were measured and the data analysed by canonical discriminant analysis. Lice show variation in morphology that is useful in identifying some of these hosts. This variation is presumably due to micro-environmental pressure provided by each host. Our interpretation is that these chewing lice have evolved to be adapted to each skua taxon; different sizes and morphologies of skua taxa result in different sizes and morphologies of Haffneria grandis and Saemundssonia.  相似文献   

11.
New taxa of grylloblattids of the family Mesorthopteridae are described from the Permian of Russia: Parastenaropodites aquilonius sp. nov. from the Soyana locality (Middle Permian); P. circumhumatus sp. nov. from the Kul’chumovo locality; and Tshermyaninus biforis gen. et sp. nov., Permorthopteron foliaceus gen. et sp. nov., Parastenaropodites pannea sp. nov., P. exossis sp. nov., Mesoidelia procera sp. nov., and M. riphaea sp. nov. from the Isady locality (Upper Permian). Two species of the genus Khosaridelia Storozhenko, 1992 (family Permotermopsidae) and one species of the genus Megakhosarina Storozhenko, 1993 (family Megakhosaridae) are transferred to the genus Parastenaropodites Storozhenko, 1996 (family Mesorthopteridae); one species of the genus Parastenaropodites is transferred to the genus Austroidelia Riek, 1954; as a result, four new combinations are established: Khosaridelia rigida Aristov, 2005 =Parastenaropodites rigidus (Aristov, 2005), comb. nov. (Vorkuta locality, Lower Permian of Russia); Khosaridelia vyatica Aristov, 2009 =Parastenaropodites vyaticus (Aristov, 2009), comb. nov. (Karaungir locality, Middle Permian of Kazakhstan); Megakhosarina intricata Aristov, 2008 =Parastenaropodites intricatus (Aristov, 2008), comb. nov. (Soyana locality, Middle Permian of Russia); and Parastenaropodites nervosa Storozhenko, 1996 =Austroidelia nervosa (Storozhenko, 1996), comb. nov. (Madygen locality, Middle Triassic of Kyrgyzstan). An identification key to species of the genus Parastenaropodites is given.  相似文献   

12.
The subfamily Apaturinae consists of 20 genera and shows disjunct distributions and unique host-plant associations. Most genera of this subfamily are distributed in Eurasia South-East Asia and Africa, whereas the genera Doxocopa and Asterocampa are distributed mainly in South America and North America, respectively. Although the Apaturinae larvae mainly feed on the Cannabaceae, those of the genus Apatura are associated with Salix and Populus (Salicaceae), which are distantly related to the Cannabaceae. Here, we infer the phylogeny of Apaturinae and reconstruct the history of host shifting and of colonization in the New World. We analyzed 9761 bp of nuclear and mitochondrial DNA sequence data, including the genes encoding EF1a, Wg, ArgK, CAD, GAPDH, IDH, MDH, RpS5, COI, COII, ATPase8, ATPase6, COIII, ND3, and ND5 for 12 apaturine genera. We also inferred the phylogeny with six additional genera using mitochondrial sequence data alone. Within the Apaturinae, two major clades are recovered in all the datasets. These clades separate the New World genera, Doxocopa and Asterocampa, indicating that dispersal to the New World occurred at least twice. According to our divergence time estimates, these genera originated during the Early Oligocene to the Early Miocene, implying that they migrated across the Bering Land Bridge rather than the Atlantic Land Bridge. The temporal estimates also show that host shifting to Salix or Populus in Apatura occurred more than 15 million years after the divergence of their host plants. Our phylogenetic results are inconsistent with the previously accepted apaturine genus groups and indicate that their higher classification should be reconsidered.  相似文献   

13.
Zygaenid moths are capable of releasing hydrogen cyanide in their defense by enzymatic break-down of cyanoglucosides, but only larvae of chalcosiine and zygaenine moths store cyanogenic compounds in cuticular cavities and thus are able to discharge defense droplets, which effectively deter potential predators. A previously proposed phylogeny of Zygaenidae hypothesized a sister group relationship of chalcosiine and zygaenine moths because of their similar larval defense system. Not all chalcosiine taxa possess cuticular cavities, however, and a comparable defense mechanism has been reported in larvae of the zygaenoid family Heterogynidae. Considering sequence data of seven molecular loci, the present study estimates the posterior probability of phylogenetic hypotheses explaining the occurrence of larval cuticular cavities. The molecular data confirm the previous exclusion of Himantopteridae from Zygaenidae and suggest their close affinity to Somabrachyidae. The sequence data also corroborate the recently proposed exclusion of the Phaudinae from the Zygaenidae, because this subfamily is recovered in a reasonably well supported species cluster consisting of members of the families Lacturidae, Limacodidae, Himantopteridae, and Somabrachyidae. We consequently agree to raise Phaudinae to family rank. Within Zygaenidae, the subfamilies Callizygaeninae, Chalcosiinae, and Procridinae most likely constitute a monophyletic group, which is sister to the Zygaeninae. Our results imply that cuticular cavities were probably present in the larvae of the most recent common ancestor of Zygaenidae. Heterogynidae cannot be confirmed as sister taxon to this family, but appear at the very first split of the Zygaenoidea, although with poor support. The specific pattern of taxa in the molecular phylogeny showing larval cuticular cavities opens the possibility that these structures could have been already present in the most recent common ancestor of the Zygaenoidea.  相似文献   

14.
15.
Periphytic ciliates play a vital role in the material cycle and energy flow of microbial food web, however, their taxonomy and biodiversity are inadequately studied given their high species richness. Two new and one little known species, viz. Derouxella lembodes gen. et sp. nov., Cyrtophoron multivacuolatum sp. nov., and Cyrtophoron apsheronica Aliev, 1991, collected from coastal waters of China, were investigated using modern methods. Derouxella gen. nov. can be recognized by having dorsoventrally flattened body, a podite, one fragmented preoral kinety, two parallel circumoral kineties, and somatic kineties progressively shortened from right to left. Morphological classification and phylogenetic analyses based on nuclear small subunit ribosomal RNA (nSSU rRNA) and mitochondrial small subunit ribosomal RNA (mtSSU rRNA) gene sequence data inferred that Derouxella gen. nov. occupies an intermediate position between Hartmannulidae and Dysteriidae. Cyrtophoron multivacuolatum sp. nov. is characterized by large body size, the numbers of somatic kineties and nematodesmal rods, and having numerous contractile vacuoles. The genus Cyrtophoron and the poorly known species C. apsheronica were redefined. Even with the addition of newly obtained nSSU rRNA and mtSSU rRNA gene sequences of Cyrtophoron, the family Chlamydodontidae was still recovered as a monophyletic group, the monophyly of Cyrtophoron was supported too.  相似文献   

16.
K W Wolf 《Bio Systems》1990,24(1):5-15
The restructuring of spermatocytes during the first meiotic division is examined in the moth Orgyia antiqua (Lymantriidae, Lepidoptera) using transmission electron microscopy. Particular emphasis was placed on the behaviour of the perispindle membrane system. These membranes develop from layers of smooth endoplasmic reticulum wrapped around the prophase I nucleus and are retained until early telophase I. The original nuclear envelope is dissolved in metaphase I. Polar fenestrae in the perispindle membrane stacks are filled with numerous irregular membrane elements. The formation of new nuclear envelopes around the daughter nuclei takes place inside the perispindle membrane system. Finally, the membrane stacks rupture concomitantly with spindle elongation in late telophase I. Thus, division of primary spermatocytes in Orgyia antiqua has a surprising degree of similarity with the so-called closed mitosis. This mode of division is typical for many protozoa, algae and fungi. In the pertinent cells, the original nuclear envelope persists around the spindle area during nuclear division. In order to distinguish the closed mitosis from the situation in Orgyia antiqua spermatocytes, the term 'sheathed nuclear division' is suggested for the latter.  相似文献   

17.
The first comprehensive phylogenetic study of Euphausiacea (all 86 valid species) is presented. It is based on four molecular markers and 168 morphological characters (including 58 characters of the petasma). Phylogenetic analyses support the monophyly and robustness of the families Bentheuphausidae and Euphausiidae and reveal three major clades for which we erect three new subfamilies: Thysanopodinae, Euphausiinae and Nematoscelinae. All genus-level clades are statistically supported (except Thysanopoda in molecular analyses), deeply nested within the subfamily-level clades, and encompass 14 new species groups. Copulatory structures have a major impact on tree topology in the morphological analysis, the removal of which resulted in only half the number of supported clades and genera. We revealed three groups of morphological characters, which are probably coupled with the same biological role and thus interlinked evolutionarily: (i) antennular peduncle and petasma (copulation); (ii) eyes and anterior thoracopods (feeding); and (iii) shape of carapace and pleon (defence). We analysed the evolutionary pathways of the clades into main oceanic biotopes and compared them with morphological adaptations most likely to be coupled with this process.  相似文献   

18.
The sequence of phosphoenolpyruvate carboxykinase (PEPCK) has been previously identified as a promising candidate for reconstructing Mesozoic-age divergences (Friedlander, Regier, and Mitter 1992, 1994). To test this hypothesis more rigorously, 597 nucleotides of aligned PEPCK coding sequence (approximately 30% of the coding region) were generated from 18 species representing Mesozoic-age lineages of moths (Insecta: Lepidoptera) and outgroup taxa. Relationships among basal Lepidoptera are well established by morphological analysis, providing a strong test for the utility of a gene which has not previously been used in systematics. Parsimony and other phylogenetic analyses were conducted on nucleotides by codon positions (nt1, nt2, nt3) separately and in combination, and on amino acids, for comparison to the test phylogeny. The highest concordance was achieved with nt1 + nt2, for which one of two most-parsimonious trees was identical to the test phylogeny, and with all nucleotides when nt3 was down-weighted sevenfold or higher, for which a single most-parsimonious tree identical to the test phylogeny resulted. Substitutions in nt3 approached saturation in many, but not all, pairwise comparisons and their exclusion or severe downweighting greatly increased the degree of concordance with the test phylogeny. Neighbor-joining analysis confirms this finding. The utility of PEPCK for phylogenetics is demonstrated over a time span for which few other suitable genes are currently available.   相似文献   

19.
Abstract.  The Saturniidae, or wild silkmoths, number approximately 1861 species in 162 genera and nine subfamilies including Cercophaninae and Oxyteninae. They include some of the largest and most spectacular of all Lepidoptera, such as the moon or luna moths, atlas moths, emperor moths, and many others. Saturniids have been important as sources of wild silk and/or human food in a number of cultures, and as models for comparative studies of genetics, development, physiology, and ecology. Seeking to improve the phylogenetic framework for such studies, we estimated relationships across Saturniidae, sampling all nine subfamilies plus all five tribes of Saturniinae. Seventy-five exemplars (45 Saturniidae plus 30 bombycoid outgroups) were sequenced for four protein-coding nuclear gene regions (5625 bp total), namely CAD (the fusion protein carbamoylphosphate synthetase/aspartate transcarbamylase/dihydroorotase), DDC (dopa decarboxylase), period, and wingless. The data, analyzed by parsimony and likelihood, gave a strongly resolved phylogeny at all levels. Relationships among subfamilies largely mirrored the pre-cladistic hypothesis of Michener, albeit with significant exceptions, and there was definitive support for the morphology-based proposal that Ludiinae form a tribe (Micragonini) within Saturniinae. In the latter subfamily, the African tribe Urotini was shown to be paraphyletic with respect to Bunaeini and Micragonini, also in accord with recent morphological findings. Relationships within the New World subfamilies Arsenurinae, Ceratocampinae and Hemileucinae nearly always accord with previous morphology-based phylogenies when both are clearly resolved. Within Hemileucinae, Hemileucini are paraphyletic with respect to the monotypic Polythysanini. A preliminary biogeographical analysis supports ancestral restriction to the New World, followed by dispersal and/or vicariance splitting most of the family into a largely New World versus a largely Old World clade.  相似文献   

20.
To understand the evolutionary history of Lymantriinae and test the present higher‐level classification, we performed the first broad‐scale molecular phylogenetic analysis of the subfamily, based on 154 exemplars representing all recognized tribes and drawn from all major biogeographical regions. We used two mitochondrial genes (cytochrome c oxidase subunit I and 16S ribosomal RNA) and six nuclear genes (elongation factor‐1α, carbamoylphosphate synthase domain protein, ribosomal protein S5, cytosolic malate dehydrogenase, glyceraldehyde‐3‐phosphate dehydrogenase and wingless). Data matrices (in total 5424 bp) were analysed by parsimony and model‐based evolutionary methods (maximum likelihood and Bayesian inference). Based on the results of the analyses, we present a new phylogenetic classification for Lymantriinae composed of seven well‐supported tribes, two of which are proposed here as new: Arctornithini, Leucomini, Lymantriini, Orgyiini, Nygmiini, Daplasini trib. nov. and Locharnini trib. nov. We discuss the internal structure of each of these tribes and address some of the more complex problems with the genus‐level classification, particularly within Orgyiini and Nygmiini.  相似文献   

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