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1.
A study was conducted on the habitat distribution of four sympatric species of Periophthalmus (the silver‐lined mudskipper Periophthalmus argentilineatus, the slender mudskipper Periophthalmus gracilis, the kalolo mudskipper Periophthalmus kalolo and the Malacca mudskipper Periophthalmus malaccensis) from northern Sulawesi. Molecular phylogenetic reconstructions based on one mtDNA marker (16S) were used to validate the morphological taxa, identifying five molecular clades. Periophthalmus argentilineatus includes two molecular species, which are named Periophthalmus argentilineatus clades F and K. Multivariate direct gradient analysis show that these species form three distinct ecological guilds, with the two molecular species occurring in different guilds. Periophthalmus clade F is ecologically eurytypic; Periophthalmus clade K and P. kalolo are prevalent in ecosystems isolated by strong oceanic currents and at shorter distances from the sea; P. gracilis plus P. malaccensis are prevalent in ecosystems connected by shallow coastal waters, in vegetated habitats at larger distances from the sea. This indicates for the first time that mudskipper species exhibit a range of adaptations to semiterrestrialism not only within genera, but even within morphospecies, delineating a much more complex adaptive scenario than previously assumed.  相似文献   

2.
Yangying Gan  Yong Liu  Fengxia Xu 《Grana》2013,52(4):271-281
The morphology of the pollen grains of 18 species representing nine genera of Annonaceae from China is described and illustrated based on observations from scanning electron microscopy (SEM). The pollen grains are small, medium-sized, large or very large, elliptic, spherical or subspherical in monads (Artabotrys, Fissistigma, Miliusa, Trivalvaria, Uvaria and most Polyalthia), tetrads (Annona, Goniothalamus, Mitrephora and Polyalthia rumphii) or octads (Disepalum). Tetragonal, tetrahedral or rhomboidal tetrads were observed in Polyalthia rumphii. Ornamentation is psilate, foveolate, perforate, rugulate, reticulate or verrucate. Most species have no visible aperture, while Miliusa balansae, Polyalthia cerasoides, Polyalthia laui, Polyalthia oblique and Trivalvaria costata have one sulcus or 1–3 pores on proximal side or globally distributed. Disepalum lagioneurum (former Polyalthia lagioneurum) bearing octads confirms its isolation from Polyalthia, which so far has been observed monad. While the isolation of Trivalvaria costata (former Polyalthia nemoralis) from Polyalthia was not supported for the similarities of pollen characters.  相似文献   

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4.
Euglena viridis (subgenus Euglena) serves as the type species for the genus Euglena. In this study, molecular phylogenetic analyses using a small subunit (SSU) and a combined SSU–partial large subunit rDNA data set for members of the genus Euglena showed that strains identified as E. viridis on the basis of morphology are distributed between two separate nonsister clades. Although all the E. viridis strains examined were morphologically indistinguishable and possessed spherical mucocysts and stellate chloroplasts with one paramylon center, there was a high degree of sequence divergence between the E. viridis strains in different clades, making this a cryptic species. Like E. viridis, all taxa from the subgenus Euglena are characterized by having one or more stellate chloroplasts with paramylon grains clustered around the center of the chloroplast. These additional taxa were divided into four clades in all the molecular analyses. Strains of Euglena stellata formed two nonsister clades whose members had a single aggregate chloroplast with paramylon center and spindle‐shaped mucocysts. A geniculata clade included species with one or two stellate chloroplasts with paramylon centers and spherical mucocysts, and the cantabrica clade had members with one stellate chloroplast with paramylon center and spherical mucocysts often arranged in spiral rows. Interspersed among these were three additional clades bearing taxa from the subgenus Calliglena that contains members with discoid plastids and pyrenoids that may or may not be capped with paramylon. These taxa formed a laciniata clade, mutabilis clade, and gracilis clade. This study demonstrates that E. viridis and E. stellata are cryptic species that can only be distinguished at the molecular level. Because E. viridis is the designated type species for the genus Euglena, we designated an epitype for E. viridis.  相似文献   

5.
A phylogenetic analysis of Euphorbiaceae sensu stricto is presented using sequences from rbcL, atpB, matK and 18S rDNA from 85 species and 83 genera. The combined analysis of four molecular markers resulted in only one most parsimonious tree and also generated new supported clades, which include Euphorbioideae + Acalyphoideae s.s., subclades A2 + A3, subclades A5 + A6 and a clade uniting subclades A2–A8 within Acalyphoideae s.s. A palisadal exotegmen is a possible synapomorphy for all the Euphorbiaceae, except for the subfamily Peroideae. The presence of vascular bundles in the inner integument and a thick inner integument were shown to be synapomorphies for the clade of inaperturate and articulated crotonoids and for the large clade of Euphorbioideae, Acalyphoideae s.s., inaperturate and articulated crotonoids, respectively. Characters of the aril and vascular bundles in the outer integument are discussed. The selected embryological characters were seen to be highly correlated with the molecular phylogeny. When the results of molecular phylogenetic analysis of a previous study and this study were adjusted along with the selected embryological characters, all clades within Euphorbiaceae were supported except for a clade comprising Euphorbioideae + Acalyphoideae s.s. + inaperturate crotonoids + articulated crotonoids + Adenoclineae s.l. and a clade uniting subclades A4–A8 within Acalyphoideae s.s. Electronic supplementary material The online version of this article (doi:) contains supplementary material, which is available to authorized users.  相似文献   

6.
Culture‐independent molecular methods based on the amplification, cloning and sequencing of small‐subunit (SSU) rRNA genes are a powerful tool to study the diversity of prokaryotic and eukaryotic microorganisms for which morphological features are not conspicuous. In recent years, molecular data from environmental surveys have revealed several clades of protists lacking cultured and/or described members. Among them are various clades of marine stramenopiles (heterokonts), which are thought to play an essential ecological role as grazers, being abundant and distributed in oceans worldwide. In this work, we show that Solenicola setigera, a distinctive widespread colonial marine protist, is a member of the environmental clade MArine STramenopile 3 (MAST‐3). Solenicola is generally considered as a parasite or an epiphyte of the diatom Leptocylindrus mediterraneus. So far, the ultrastructural, morphological and ecological data available were insufficient to elucidate its phylogenetic position, even at the division or class level. We determined SSU rRNA gene sequences of S. setigera specimens sampled from different locations and seasons in the type locality, the Gulf of Lions, France. They were closely related, though not identical, which, together with morphological differences under electron microscopy, suggest the occurrence of several species. Solenicola sequences were well nested within the MAST‐3 clade in phylogenetic trees. Since Solenicola is the first identified member of this abundant marine clade, we propose the name Solenicolida for the MAST‐3 phylogenetic group.  相似文献   

7.
Pallenopsis patagonica (Hoek, 1881) is one of the most taxonomically problematic and variable pycnogonid species, and is distributed around the southern South American coast, and the Subantarctic and Antarctic areas. We conducted a phylogenetic analysis of mitochondrial cytochrome c oxidase subunit I (COI) sequences of 47 Pallenopsis specimens, including 39 morphologically identified as P. patagonica, five Pallenopsis pilosa (Hoek, 1881), one Pallenopsis macneilli Clark, 1963, one Pallenopsis buphtalmus Pushkin, 1993, and one Pallenopsis latefrontalis Pushkin, 1993. Furthermore, we studied morphological differences between the different COI lineages using light and scanning electron microscopy, including also material from Loman's and Hedgpeth's classical collections, as well as Hoek's type material of P. patagonica from 1881. The molecular results unambiguously reveal that P. patagonica is a complex of several divergent clades, which also includes P. macneilli, P. buphtalmus, and P. latefrontalis. Based on the material available, two major clades could be identified, namely a ‘Falkland’ clade, to which we assign the nominal P. patagonica, and a ‘Chilean’ clade, which is distinct from the ‘Falkland’ clade. We describe the ‘Chilean’ clade as new species, P allenopsis yepayekae sp. nov. Weis, 2013. All molecular results are confirmed by specific morphological characteristics that are discussed in detail and compared with Pallenopsis species closely related to the P. patagonica complex. Our results reveal that P. patagonica is a species‐rich complex that is in need for a thorough taxonomic revision, using both morphological and genetic approaches. © 2014 The Linnean Society of London  相似文献   

8.
This study investigates the molecular phylogeny of seven lionfishes of the genera Dendrochirus and Pterois. MP, ML, and NJ phylogenetic analysis based on 964 bp of partial mitochondrial DNA sequences (cytochrome b and 16S rDNA) revealed two main clades: (1) “Pterois” clade (Pterois miles and Pterois volitans), and (2) “Pteropterus–Dendrochirus” clade (remainder of the sampled species). The position of Dendrochirus brachypterus either basal to the main clades or in the “Pteropterus–Dendrochirus” clade cannot be resolved. However, the molecular phylogeny did not support the current separation of the genera Pterois and Dendrochirus. The siblings P. miles and P. volitans are clearly separated and our results support the proposed allopatric or parapatric distribution in the Indian and Pacific Ocean. However, the present analysis cannot reveal if P. miles and P. volitans are separate species or two populations of a single species, because the observed separation in different clades can be either explained by speciation or lineage sorting. Molecular clock estimates for the siblings P. miles and P. volitans suggest a divergence time of 2.4–8.3 mya, which coincide with geological events that created vicariance between populations of the Indian and Pacific Ocean.  相似文献   

9.
Pseudonaja is a clade of seven nominal species of elapid snakes distributed throughout Australia and in southern New Guinea. The species‐level systematics of this group is generally considered to be problematic. A recent phylogenetic analysis of mitochondrial DNA sequences for a geographically extensive series of Pseudonaja specimens revealed nine major clades, of which six largely coincide with nominal species (P. affinis, P. guttata, P. inframacula, P. ingrami, P. modesta and P. textilis). The three remaining clades are composed of specimens currently referred to P. nuchalis. This paper presents a multivariate analysis of 30 morphometric variables recorded for 220 specimens, representing the P. affinis, P. inframacula, P. textilis and three P. nuchalis clades (P. guttata, P. ingrami and P. modesta are well‐demarcated species and, accordingly, were not considered). The morphometric data readily separate these putative lineages, affording compelling evidence that they constitute evolutionary species. The names aspidorhyncha and mengdeni are resurrected for two of the three species presently recognized as P. nuchalis. These species, P. affinis, P. inframacula, P. nuchalis and P. textilis are redescribed. © 2009 The Linnean Society of London, Zoological Journal of the Linnean Society, 2009, 155 , 171–197.  相似文献   

10.
Phylogenetic relationships, limits of species, and genera within Lycoperdaceae, were inferred by use of ITS and LSU nu-rDNA sequence data. Lycoperdaceae was confirmed as monophyletic, and Mycenastrum corium as a sister taxon to the ingroup. Four major clades were identified and received weak to moderate support and correspond with the genera Lycoperdon, Bovista, Calvatia, and Disciseda. The Lycoperdon clade includes species from Lycoperdon, Vascellum, Morganella, Handkea, Bovistella, and Calvatia. The structure within the Lycoperdon clade is unresolved and several clades are more or less unsupported, which suggests treating the supported Lycoperdon clade as the genus Lycoperdon. L. nigrescens and L. caudatum occur on single branches and their phylogenetic positions could not be resolved. The phylogenetic analyses identified 31 species of Lycoperdon, 11 species of Bovista, six species of Calvatia, and two species of Disciseda. In Lycoperdon three new species were recognized. A new species closely related to B. limosa is identified and discussed. A classification of Lycoperdaceae is proposed based on the results of the phylogenetic analyses. Morphological characters of species within and among identified clades are discussed.  相似文献   

11.
Straight‐billed Hermit Phaethornis bourcieri inhabits the understorey of upland terra firme forest throughout most of the Amazon basin. Currently, two allopatric taxa regarded as subspecies are recognized: P. b. bourcieri and P. b. major. However, the validity, interspecific limits and evolutionary history of these taxa are not yet fully elucidated. We use molecular characters to propose a phylogenetic hypothesis for populations and taxa grouped under Phaethornis bourcieri. Our results showed that P. bourcieri is part of the ‘Ametrornis’ clade, along with Phaethornis philippii and Phaethornis koepckeae, and that the subspecies major is more closely related to the latter two species than to populations grouped under nominate bourcieri. Our phylogenetic hypotheses recovered three main reciprocally monophyletic clades under nominate bourcieri separated by the lower Negro River and the Branco River or the Branco–Negro interfluve (clades B and C) and the upper Amazon (Solimões) or lower Marañon/Ucayali Rivers (clades C and D). Based on multi‐locus phylogeographic and population genetics approaches, we show that P. b. major is best treated as a separate species, and that P. b. bourcieri probably includes more than one evolutionary species, whose limits remain uncertain. The diversification of the ‘Ametrornis’ clade (P. bourcieri, P. philippii and P. koepckeae) is centred in the Amazon and appears to be closely linked to the formation of the modern Amazon drainage during the Plio‐Pleistocene.  相似文献   

12.
In this study, we used sequences of two mitochondrial genes, cytochrome c oxidase I (COI) and 16S rRNA, and one nuclear gene, 28S rRNA, to test the monophyly of the sea star genus Echinaster, and understand the phylogenetic relationships among species and subgenera within this genus. Phylogenetic analyses based on Bayesian inference and maximum likelihood methods revealed three clades with high values of genetic divergence among them (K2P distances for COI over 23%). One of the clades grouped all Echinaster (Othilia) species, and the other two clades included Echinaster (non‐Othilia) species and Henricia species, respectively. Although the relationships among Henricia, Othilia, and Echinaster could not be completely clarified, the Othilia clade was a well‐supported group with shared diagnostic morphological characters. Moreover, the approximately unbiased test applied to the phylogenetic reconstruction rejected the hypothesis of the genus Echinaster as a monophyletic group. According to these results, we suggest the revalidation of Othilia as a genus instead of a subgenus within Echinaster. Our study clarifies important points about the phylogenetic relationships among species of Echinaster. Other important systematic questions about the taxonomic classification of Echinaster and Henricia still remain open, but this molecular study provides bases for future research on the topic.  相似文献   

13.
Parthenocissus (the Virginia creeper genus, Vitaceae) consists of 13 species and shows a disjunct distribution between Asia and North America. We investigated the inflorescence structure, calyx morphology, appendages on the inner side of petals, leaf epidermis, pollen and seed characters throughout the genus. A combined phylogenetic analysis with 27 morphological and 4137 molecular characters was conducted and the result was largely congruent with that of the previous molecular work, but with higher resolution. The combined analysis identified two clades corresponding to the Asian and North American taxa. Parthenocissus feddei was resolved as closely related to the clade containing P. cuspidifera, P. heterophylla and P. semicordata. The four species share synapomorphies of having conspicuously raised veinlets, an obscurely five‐ (to eight‐) lobed calyx, appendages on the inner side of petals covering the entire length of anthers and foveolate pollen exine ornamentation. Within the Old World clade, the pentafoliolate species were weakly supported as more closely related to species with both simple and trifoliolate leaves. Furthermore, the ancestral states of tendril apices, inflorescence structure, appendages on the inner side of petals and exine ornamentation of pollen grains were reconstructed on the molecular strict consensus tree. The appendages on the inner side of petals and exine ornamentation of pollen grains were suggested to be important characters in the taxonomy of Parthenocissus, especially for species with trifoliolate leaves. Finally, the previous classifications of Parthenocissus were evaluated within the phylogenetic framework. © 2011 The Linnean Society of London, Botanical Journal of the Linnean Society, 2011, ?? , ??–??.  相似文献   

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Ferula L. is one of the most species-rich and taxonomically difficult genera of Apiaceae. In this study, we obtained nrDNA ITS sequences of seven poorly known species of Ferula (Ferula anatolica, Ferula sp. (tentatively identified as F. candelabrum by collectors), F. drudeana, F. huber-morathii, F. marmarica, F. talassica, and F. tunetana) and explored their phylogenetic positions using 148 ITS sequences of the subtribe Ferulinae from GenBank. Five of these newly sequenced species fall into three groups, corresponding to clades recognized in earlier molecular studies. Ferula sp. are added to clade, which is mostly composed of Central Asian species. This placement showed that identification as F. candelabrum was erroneous. The second clade, which is mostly composed of Mediterranean taxa, includes two species from North Africa: F. marmarica and F. tunetana. Despite the well-supported monophyly of this clade, the relationships inside this group need to be revised, as broadly distributed F. communis is paraphyletic with respect to other species. Ferula drudeana and F. huber-morathii, two narrow endemics from Turkey, are placed in the Central Asian clade. Two species, F. anatolica and F. talassica, do not fall into any of the recognized clades. In addition, we examined the sequence variation of three potentially highly variable pDNA regions, the trnH-psbA, trnS-trnG, and atpB-rbcL intergenic spacers, for a subset of 18 specimens. The resulting pDNA and ITS based phylogenetic trees were incongruent, as supported by significant ILD tests. The cause of this incongruence can be manifold, including hybridization, a lack of a phylogenetic signal, and homoplastic substitutions. Our analyses suggest that only trnS-trnG can be added to the list of pDNA markers used for phylogenetic studies of Ferula, as it has the highest number of parsimony informative characters and is easy to amplify from degraded material.  相似文献   

16.
The river‐weed family Podostemaceae (c. 300 species in c. 54 genera) shows a number of morphological innovations to be adapted to its unusual aquatic habitat, and its unique or rare bauplan features have been reflected in the traditional (i.e. non‐molecular) classification recognizing numerous monotypic or oligospecific genera. The infrasubfamilial relationships of many genera remained unclear. The present study used molecular phylogenetic analysis of matK sequences for 657 samples (c. 132 species/c. 43 genera). The family was traditionally divided into three subfamilies (Podostemoideae, Tristichoideae and Weddellinoideae). American Podostemoideae were shown to be polyphyletic and divided into four clades, i.e. Ceratolacis, Diamantina, Podostemum and all other genera. Among the podostemoid clades, Diamantina was the first branching clade and a clade comprising Mourera and the Apinagia subclade was then sister to the remainder of the New World and Old World Podostemoideae with low statistic supports. The Old World Podostemoideae comprised four monophyletic clades, i.e. two African clades, one Madagascan clade and one Asian clade, although the relationships among these clades and American Ceratolacis and Podostemum were poorly resolved. African Podostemoideae were polyphyletic, with Saxicolella pro parte being weakly supported as sister to the remaining Old World Podostemoideae plus Ceratolacis and Podostemum. In contrast to the American and African clades, monophyly of four Asian subclades was well supported. Plants of Tristicha (Tristichoideae) and of Weddellina (Weddellinoideae), which are currently treated as monospecific, had great matK differentiation equivalent to at least interspecific variation. © 2012 The Linnean Society of London, Botanical Journal of the Linnean Society, 2012, 169 , 461–492.  相似文献   

17.
Until recently, Histoplasma capsulatum was believed to harbour three varieties, var. capsulatum (chiefly a New World human pathogen), var. duboisii (an African human pathogen) and var. farciminosum (an Old World horse pathogen), which varied in clinical manifestations and geographical distribution. We analysed the phylogenetic relationships of 137 individuals representing the three varieties from six continents using DNA sequence variation in four independent protein‐coding genes. At least eight clades were idengified: (i) North American class 1 clade; (ii) North American class 2 clade; (iii) Latin American group A clade; (iv) Latin American group B clade; (v) Australian clade; (vi) Netherlands (Indonesian?) clade; (vii) Eurasian clade and (viii) African clade. Seven of eight clades represented genetically isolated groups that may be recognized as phylogenetic species. The sole exception was the Eurasian clade which originated from within the Latin American group A clade. The phylogenetic relationships among the clades made a star phylogeny. Histoplasma capsulatum var. capsulatum individuals were found in all eight clades. The African clade included all of the H. capsulatum var. duboisii individuals as well as individuals of the other two varieties. The 13 individuals of var. farciminosum were distributed among three phylogenetic species. These findings suggest that the three varieties of Histoplasma are phylogenetically meaningless. Instead we have to recognize the existence of genetically distinct geographical populations or phylogenetic species. Combining DNA substitution rates of protein‐coding genes with the phylogeny suggests that the radiation of Histoplasma started between 3 and 13 million years ago in Latin America.  相似文献   

18.
The type materials of Paecilomyces sinensis, including herbarium specimen and ex-type strain, were re-examined to clarify its relationships with other species. Morphological observations on the strain grown in various culture media revealed that the fungus was morphologically related to Polycephalomyces, since it produced conidial mass and lanceolate or narrowly lageniform phialides. Six genes, including ITS, nrSSU, nrLSU, tef1, rpb1 and rpb2, were amplified from the type materials and used in phylogenetic analyses to determine the systematic position of the fungus in the framework of clavicipitaceous fungi. The results place P. sinensis with Polycephalomyces formosus, the type species of Polycephalomyces, and Cordyceps ramosopulvinata forming a clade unaffiliated with the known families of clavicipitaceous fungi. Based on both morphological and molecular data, a new combination, Polycephalomyces sinensis, is proposed for Paecilomyces sinensis. The new clade found in this study is designated as Polycephalomyces clade and expands the phylogenetic diversity for clavicipitaceous fungi. The teleomorph–anamorph connection between Berkelella and Polycephalomyces previously conceived cannot be retained as the type species of Polycephalomyces, P. formosus, is closely linked to species of Cordyceps s.l. in the new clade.  相似文献   

19.
The phylogenetic relationships within the genus Plecotus were assessed using molecular as well as morphological methods. With only three species missing, our study is based on an almost comprehensive taxonomic sampling. The genetic analysis comprised 151 individuals from throughout the range. Sequences of two mitochondrial sections, parts of the 16S rRNA gene (16S) and of the control region (CR) were analysed. The morphological analysis of cranial and external characters comprised 697 individuals, including 10 holotypes and one lectotype. Data from 15 craniometric characters of 442 specimens were used in the multivariate analyses. The molecular data identified nine primary clades representing 11 species, 10 of which could be assigned to described taxa, whereas one was described as a new species, Plecotus strelkovi Spitzenberger sp. nov. The tree based on 16S revealed two major lineages, one consisting of only one primary clade restricted to the Mediterranean, the other consisting of eight primary clades representing Eurasian taxa. The morphological analysis revealed five additional species, two of them not described. Together with the recently described P. taivanus, P. sardus and P. balensis, which were not included in our analysis, the genus Plecotus comprises at least 19 more or less cryptic species. Phylogenetic and phenetic analyses resulted in similar but not completely concordant arrangements of the species. The proposed classification relies mainly on the tree based on 16S sequences. The current distribution indicates that 16 species can be linked to arboreal refugia, three to eremial refugia. We assume that speciation within the gleaning, rather slow flying long‐eared bats is due to a multitude of disruption and isolation processes within a formerly continuous range of the broad‐leaved Arcto‐Tertiary forest in which Plecotus probably originated. An exact calibrated molecular dating of the splits is not possible. The Early Oligocene age of the presumed ancestor of the Plecotini and a correlation of the molecular diversifications with palaeogeographic reconstructions suggest that the divergence of the two major lineages may have occurred already during the Middle Miocene, 14.5 Mya.  相似文献   

20.
Our recent molecular phylogenetic study revealed a previously unrecognized clade of six species that is sister to Elaphoglossum. Within this clade, four species are currently classified in Bolbitis, one in Lomagramma, and one in Acrostichum. For this clade, we propose the name Mickelia, with M. nicotianifolia as the type species. We also make new combinations for the species in our phylogenetic study shown to belong to Mickelia (M. bernoullii, M. guianensis, M. hemiotis, M. nicotianifolia, M. oligarchica, and M. scandens) and two other species believed to belong to the clade based on morphology (M. lindigii, M. pergamentacea). A new hybrid and two new species are also described (M. ×atrans, M. furcata, and M. pradoi). In total, Mickelia consists of ten species and one hybrid. It is entirely neotropical. We provide a key to the genera of bolbitidoid ferns and a synopsis of Mickelia that gives for each species a complete synonymy, geographical distribution, comparative discussion, and illustration.  相似文献   

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