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1.
Specimens of moth flies (Diptera: Psychodidae: Psychodinae) were sampled in southwest Anatolia and the European part of Turkey between 2003 and 2009. Samples contained nine species new to science: Ulomyia asiaminorica sp. n., Pneumia pellucida sp. n., Berdeniella turcica sp. n., B. aktashi sp. n., Clytocerus thracicus sp. n., Jungiella afyonica sp. n., J. geniculatoides sp. n., J. barlasi sp. n., and Telmatoscopus remotus sp.n. The new species are described and illustrated. Distributional data for a total of 45 species are provided. 63 species of Psychodinae are now known to occur in Turkey.  相似文献   

2.
Twenty‐six strains morphologically identified as Cylindrospermum as well as the closely related taxon Cronbergia siamensis were examined microscopically as well as phylogenetically using sequence data for the 16S rRNA gene and the 16S‐23S internal transcribed spacer (ITS) region. Phylogenetic analysis of the 16S rRNA revealed three distinct clades. The clade we designate as Cylindrospermum sensu stricto contained all five of the foundational species, C. maius, C. stagnale, C. licheniforme, C. muscicola, and C. catenatum. In addition to these taxa, three species new to science in this clade were described: C. badium, C. moravicum, and C. pellucidum. Our evidence indicated that Cronbergia is a later synonym of Cylindrospermum. The phylogenetic position of Cylindrospermum within the Nostocaceae was not clearly resolved in our analyses. Cylindrospermum is unusual among cyanobacterial genera in that the morphological diversity appears to be more evident than sequence divergence. Taxa were clearly separable using morphology, but had very high percent similarity among ribosomal sequences. Given the high diversity we noted in this study, we conclude that there is likely much more diversity remaining to be described in this genus.  相似文献   

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The subfamily Crucigenioideae was traditionally classified within the well‐characterized family Scenedesmaceae (Chlorophyceae). Several morpho‐logical revisions and questionable taxonomic changes hampered the correct classification of crucigenoid species resulting in a high number of synonymous genera. We used a molecular approach to determine the phylogenetic position of several Tetrastrum and Crucigenia species. The molecular results were correlated with morphological and ontogenetic characters. Phylogenetic analyses of the SSU rDNA gene resolved the position of Tetrastrum heteracanthum and T. staurogeniaeforme as a new lineage within the Oocystis clade of the Trebouxiophyceae. Crucigenia tetrapedia, T. triangulare, T. punctatum, and T. komarekii were shown to be closely related to Botryococcus (Trebouxiophyceae) and were transferred to Lemmer‐mannia. Crucigenia lauterbornii was not closely related to the other Crucigenia strains, but was recovered within the Chlorella clade of the Trebouxiophyceae.  相似文献   

5.
The genus Coleochaete Bréb. is considered to be a key taxon in the evolution of green algae and embryophytes (land plants), but only a few of the approximately 15 species have been studied with molecular phylogenetic methods. We report here the sequences of the gene rbcL from six new cultures of Coleochaete and two of Chaetosphaeridium Klebahn. These sequences were combined with 32 additional sequences, and phylogenetic analyses were performed with maximum likelihood, distance optimality, and parsimony methods. Important subgroups within Coleochaete include two primary lineages, one marked by fully corticated zygotes and the other by naked or weakly corticated zygotes. In the first lineage there is a subclade with tightly joined filaments and distinctive (“T‐shaped”) cell division, an assemblage of strains that resembles the endophytic species Coleochaete nitellarum Jost, and a clade with loosely joined filaments and “Y‐shaped” cell divisions. Consistent with recent multigene phylogenies, these analyses support the monophyly of the Coleochaetales, place the Charales as the sister taxon to land plants, and indicate that Chaetosphaeridium is far more closely related to Coleochaete than to Mesostigma Lauterborn.  相似文献   

6.
The genus Paegniodes Eaton, 1881 and its type species P. cupulatus (Eaton, 1871) have never been described in detail completely. In this article, all stages are described and photographed. Compared to other heptageniid genera, the adults of P. cupulatus have a more colourful body, smaller hindwings but larger titillators. The nymphs of this species have no setae or tubercles on the body and no emarginations on the head capsule. They have smaller lamellae of the first gills, a wider labrum with a median notch, mandibles without setae on outer margins, maxillae with a row of setae and scattered setae on the ventral surface, cerci with mesal setae, and a median filament with setae on both sides. Both imaginal and nymphal stages of the genus have unique characters, so the taxon Paegniodes is recognized at the rank of genus here. It appears closely related to Rhithrogena Eaton, 1881.  相似文献   

7.
Samuli Lehtonen   《Aquatic Botany》2009,91(4):279-290
The phylogenetic relationships of aquatic plant families Alismataceae and Limnocharitaceae were investigated by cladistic analysis of morphological and cytological characters. The use of morphological data allowed much wider taxon sampling than in recent molecular studies, and resulted in several new hypotheses. Limnocharitaceae was resolved as a paraphyletic group giving rise to the monophyletic Alismataceae, contradicting with the results from molecular studies. Most of the currently accepted genera were relatively well supported as monophyletic groups, with polyphyletic Caldesia and paraphyletic Limnophyton as notable exceptions. Phylogenetic relationships between different genera remained poorly supported, but it is suggested that the base chromosome number n = 11 is derived from the plesiomorphic n = 7.  相似文献   

8.
The mouse opossums of the genus Thylamys constitute a group of species mainly adapted to open xeric‐like habitats and restricted to the southern portion of South America. We used molecular data (mitochondrial and nuclear sequences) to evaluate the phylogenetic and biogeographical relationships of all currently known living species of the genus, recognizing a new taxon from the middle and high elevations of the Peruvian Andes and evaluating the phylogenetic structuring within T. pallidior and T. elegans, as well as the validity of T. sponsorius, T. cinderella and T. tatei, and the haplogroups recognized within T. pusillus. Our results confirm the monophyly of the genus and that the Caatinga and the Cerrado inhabitants Thylamys karimii and T. velutinus are the most basal species in the radiation of Thylamys. We also calibrated a molecular clock which hypothesized a time of origin of the genus of about 24 My, with most species differentiating in middle and late Miocene and Plio‐Pleistocene times of South America.  相似文献   

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The morphologically unique ciliate Psammomitra has long been considered as a systematically uncertain stichotrich. This is mainly because of its highly specialized morphology and a lack of either detailed information concerning its ontogenesis, or molecular data. Based on the small subunit rRNA (SSrRNA) gene and alpha‐tubulin gene sequences, we re‐evaluated the phylogenetic position of Psammomitra retractilis using multiple algorithms. Phylogenetic trees inferred from the SSrRNA gene sequences representing a total of 53 spirotrichs demonstrated the closest relationship of Psammomitra was with Holosticha‐like taxa, with strong support, which clearly suggested that Psammomitra should be placed into the order Urostylida although it branched at a rather deep level, and is likely to be closely related to Holostichidae. With consideration to molecular evidence and morphological characters, Psammomitra should be a clearly outlined taxon at about the rank of family, i.e. Psammomitridae stat. nov. , within the order Urostylida. The improved diagnosis for this family is as follows: Urostylida possessing extremely contractile, elongated body which consists of three parts: head, trunk, and slender tail; midventral complex composed of midventral pairs only and restricted to about anterior 1/3 of ventral surface; frontal, frontoterminal, and transverse cirri present; one left and one right marginal rows which commence near proximal end of adoral zone and extend to near rear body end.  相似文献   

11.
We examined a cranial morphometric data set consisting of 186 specimens from the entire distribution range of Ochotona pallasii sensu lato and O. argentata, as well as 67 complete sequences of the COI gene and 28 sequences of the MGF and PRKCI introns from these and closely allied species. Our results show that the two allopatric morphologically similar taxa composing Opallasii sensu lato – from Mongolia and adjacent territories and Kazakhstan – are paraphyletic relative to O. argentata. Genetic distances between these three taxa are larger than the intraspecific variation known for the subgenus Pika, in which the species under consideration belong; these distances are even larger than the interspecific differences among closely related species such as O. hyperborea, O. mantchurica and O. hoffmanni. Thus, the three focal taxa are recognized here as distinct species. Inspection of the type specimen of Opallasii indicated that this specimen was not collected in Kazakhstan, has previously been theorized. The most probable place of the holotype's origin is Russian south‐eastern Altai (Chuyskaya Steppe); whatever its exact origin, it definitively originates from the ‘Mongolian’ taxon. Based on this evidence, the senior synonym for the Kazakh pika is O. opaca Argyropulo, 1930. Thus, we propose to recognize three separate species in the Opallasii species group: Opallasii (Mongolia and adjacent territories), O. opaca (eastern Kazakhstan) and O. argentata (Helan Shan Range, China).  相似文献   

12.
Taxa missing large amounts of data pose challenges that may hinder the recovery of a well‐resolved, accurate phylogeny and leave questions surrounding their phylogenetic position. Systematists commonly have to contend with one or two species in a group for which there is little or no material available suitable for recovering molecular data. It is unclear whether these taxa can be better placed using analyses based on morphological data only, or should be included in broader analyses based on both morphological and molecular data. The extinct madtom catfish Noturus trautmani is known from few specimens for which molecular data are unavailable. We included this taxon in parsimony and Bayesian analyses of relationships of madtom catfishes based on a combination of morphological and molecular data. Results indicate that using a combination of morphological and molecular data does a better job at providing a phylogenetic placement for N. trautmani than morphology alone, even though it is missing all of its molecular characters. We provide a novel hypothesis of relationships among Noturus species and recommendations for classification within the group. © 2009 The Linnean Society of London, Zoological Journal of the Linnean Society, 2009, 155 , 60–75.  相似文献   

13.
Analyses of the mitochondrial cox1, the nuclear‐encoded large subunit (LSU), and the internal transcribed spacer 2 (ITS2) RNA coding region of Pseudo‐nitzschia revealed that the P. pseudodelicatissima complex can be phylogenetically grouped into three distinct clades (Groups I–III), while the P. delicatissima complex forms another distinct clade (Group IV) in both the LSU and ITS2 phylogenetic trees. It was elucidated that comprehensive taxon sampling (sampling of sequences), selection of appropriate target genes and outgroup, and alignment strategies influenced the phylogenetic accuracy. Based on the genetic divergence, ITS2 resulted in the most resolved trees, followed by cox1 and LSU. The morphological characters available for Pseudo‐nitzschia, although limited in number, were overall in agreement with the phylogenies when mapped onto the ITS2 tree. Information on the presence/absence of a central nodule, number of rows of poroids in each stria, and of sectors dividing the poroids mapped onto the ITS2 tree revealed the evolution of the recently diverged species. The morphologically based species complexes showed evolutionary relevance in agreement with molecular phylogeny inferred from ITS2 sequence–structure data. The data set of the hypervariable region of ITS2 improved the phylogenetic inference compared to the cox1 and LSU data sets. The taxonomic status of P. cuspidata and P. pseudodelicatissima requires further elucidation.  相似文献   

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DNA sequences from type material in the nongeniculate coralline genus Lithophyllum were used to unambiguously link some European species names to field‐collected specimens, thus providing a great advance over morpho‐anatomical identifi‐cation. In particular, sequence comparisons of rbcL, COI and psbA genes from field‐collected specimens allowed the following conclusion: the generitype species, L. incrustans, occurs mostly as subtidal rhodoliths and crusts on both Atlantic and Mediterranean coasts, and not as the common, NE Atlantic, epilithic, intertidal crust reported in the literature. The heterotypic type material of L. hibernicum was narrowed to one rhodolith belonging in Lithophyllum. As well as occurring as a subtidal rhodolith, L. hibernicum is a common, epilithic and epizoic crust in the intertidal zone from Ireland south to Mediterranean France. A set of four features distinguished L. incrustans from L. hibernicum, including epithallial cell diameter, pore canal shape of sporangial conceptacles and sporangium height and diameter. An rbcL sequence of the lectotype of Lithophyllum bathyporum, which was recently proposed to accommodate Atlantic intertidal collections of L. incrustans, corresponded to a distinct taxon hitherto known only from Brittany as the subtidal, bisporangial, lectotype, but also occurs intertidally in Atlantic Spain. Specimens from Ireland and France morpho‐anatomically identified as L. fasciculatum and a specimen from Cornwall likewise identified as L. duckerae were resolved as L. incrustans and L. hibernicum, respectively.  相似文献   

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Map turtles of the genus Graptemys are native to North America, where a high degree of drainage endemism is believed to have shaped current diversity. With 14 species and one additional subspecies, Graptemys represents the most diverse genus in the family Emydidae. While some Graptemys species are characterized by pronounced morphological differences, previous phylogenetic analyses have failed yet to confirm significant levels of genetic divergence for many taxa. As a consequence, it has been debated whether Graptemys is taxonomically inflated or whether the low genetic divergence observed reflects recent radiations or ancient hybridization. In this study, we analysed three mtDNA blocks (3228 bp) as well as 12 nuclear loci (7844 bp) of 89 specimens covering all species and subspecies of Graptemys. Our analyses of the concatenated mtDNA sequences reveal that the widespread G. geographica constitutes the sister taxon of all other Graptemys species. These correspond to two clades, one comprised of all broad‐headed Graptemys species and another clade containing the narrow‐headed species. Most species of the broad‐headed clade are reciprocally monophyletic, except for G. gibbonsi and G. pearlensis, which are not differentiated. By contrast, in the narrow‐headed clade, many currently recognized species are not monophyletic and divergence is significantly less pronounced. Haplotype networks of phased nuclear loci show low genetic divergence among taxa and many shared haplotypes. Principal component analyses using coded phased nuclear DNA sequences revealed eight distinct clusters within Graptemys that partially conflict with the terminal mtDNA clades. This might be explained by male‐mediated gene flow across drainage basins and female philopatry within drainage basins. Our results support that Graptemys is taxonomically oversplit and needs to be revised.  相似文献   

18.
ABSTRACT. Colonial volvocaleans (Chlorophyceae) are used as a standard model of multicellular evolution. However, the phylogenetic position of the colonial volvocalean family Spondylomoraceae has yet to be resolved. To examine this, the molecular phylogenies of Pyrobotrys stellata and Pyrobotrys squarrosa were analyzed using combined 18S rRNA, RUBISCO large subunit, and P700 chl a‐apoprotein A2 gene sequences. In the phylogenetic trees, Pyrobotrys belonged to the clade Caudivolvoxa and was not closely related to other colonial volvocalean flagellates. The results indicate that colony formation of Spondylomoraceae independently evolved from unicellular volvocaleans. The phylogenetic position of problematic “Pascherina tetras” SAG 159‐1 was also analyzed.  相似文献   

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Eremiadinae, one of three subfamilies of Lacertidae, are distributed throughout Asia and Africa. Previous phylogenetic studies suggested that one of the main groups of Eremiadinae (the Ethiopian clade) consist of two clades with predominately East‐African and South‐African distribution. Yet, especially the latter one, which includes the genera Pedioplanis, Meroles, Ichnotropis, Tropidosaura and Australolacerta, was not well supported in the molecular phylogenetic analysis. In this study, we analysed the phylogenetic relationships among the genera of the ‘South African clade’ to assess whether this group actually forms a highly supported clade and to address questions concerning the monophyly of the genera. We sequenced sections of the widely used mitochondrial genes coding for 16S rRNA, 12S rRNA and cytochrome b (altogether 2045 bp) as well as the nuclear genes c‐mos, RAG‐1, PRLR, KIF24, EXPH5 and RAG‐2 (altogether 4473 bp). The combined data set increased the support values for several nodes considerably. Yet, the relationships among five major lineages within the ‘South African clade’ are not clearly resolved even with this large data set. We interpret this as a ‘hard polytomy’ due to fast radiation within the South African lacertids. The combined tree based on nine marker genes provides strong support for the ‘South African Clade’ and its sister group relationship with the ‘East African Clade’. Our results confirm the genus Tropidosaura as a monophylum, while Ichnotropis is paraphyletic in our trees: Ichnotropis squamulosa appears more closely related to Meroles than to Ichnotropis capensis. Furthermore, the monophyly of Meroles is questionable as well. Based on our results, I. squamulosa should be transferred from Ichnotropis into the genus Meroles. Also, the two species of Australolacerta (A. australis and A. rupicola) are very distantly related and the genus is perhaps paraphyletic, too. Finally we propose a phylogeographical scenario in the context of palaeoclimatic data and compare it with a previously postulated hypothesis.  相似文献   

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