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1.
The genus Auletobius in the Russian fauna is revised. Five species (A. egorovi, A. irkutensis, A. puberulus, A. sanguisorbae, and A. submaculatus) belonging to two subgenera are revealed. The distribution of these species in Russia is given. The data on the trophic associations of the species are summarized. Keys to the subtribes of the tribe Auletini, subgenera of the genus Auletobius, and species of the subgenus Auletobius s. str. are given. All the taxa are redescribed.  相似文献   

2.
In the tribe Cynareae the genus Carlina is a well limited taxon. The sequence of leaves and involucral bracts, and the form of heads are important characters for identification. The genus is classified into the subgenera Carlowizia, Lyrolepis, and Carlina. The ancestral subgenera Carlowizia and Lyrolepis are endemits of the Canary islands respectively the south Aegean islands. The very variable species of the Mediterranean-Central European-West Asian subgenus Carlina are divided into sect. Corymbosae, sect. Mitina, sect. Carlina, and sect. Heteracantha. These sections are well distinguished by several morphological and anatomical features. A new species C. kurdica) is described from north-west Iraq.  相似文献   

3.
Ultrastructural investigations on many isolates ofTetraselmis have revealed that the species have characteristic fine structural features of the pyrenoid and it was proposed (Horiet al., 1982) that the genus be subdivided into four subgenera. In the present study of this series, species of the subgenusPrasinocladia, includingTetraselmis marina, T. verrucosa andT. verrucosa f.rubens, are described in detail.  相似文献   

4.
Five new species, Petrobius caucasicus sp. n., Trigoniophthalmus presimplex sp. n., T. divnogorski sp. n., T. kislovodski sp. n., and T. adigei sp. n. (Machilidae), are described from the Caucasus. A key to all the known species of the genus Trigoniophthalmus is given. Two subgenera (Trigoniophthalmus s. str., Trigoniocellus subgen. n.) in the genus Trigoniophthalmus are described. 2 + 2 retractile vesicles are present on abdominal segments II–IV in the species of Trigoniocellus subgen. n. and on II–V abdominal segments in Trigoniophthalmus s. str. Analysis of the evolution and phylogenetic relations between the species of the genus Trigoniophthalmus is performed for the first time. The formation of bristletails of the genus Trigoniophthalmus appears to occur in the Caucasian mountain province of the European area, from where they penetrated to the Central European mixed province and the Mediterranean subarea. Among the described species of the genus, T. kislovodski is distinguished by the greatest number of plesiomorphic states of morphological characters.  相似文献   

5.
6.
The genus Deporaus from the Russian fauna is revised. Four species (D. pacatus, D. azarovae, D. septentrionalis, and D. hartmanni) of the subgenera Pseudapoderites and Japonodeporaus are found. Keys to the subgenera and to the species of the subgenus Pseudapoderites are given. The genus Deporaus, subgenera Pseudapoderites and Japonodeporaus, and four species are redescribed. The distribution of these species in Russia is discussed.  相似文献   

7.
8.
The genus Betula comprises various species in boreal and temperate climate zones of the Northern Hemisphere. The taxonomy of Betula is controversial and complicated by parallel evolution of morphological traits, polyploidization events, and extensive hybridization and introgression among species. Multilocus molecular data from AFLPs were used to provide phylogenetic information. A large number of polymorphic markers (321 variable bands) were produced in 107 Betula accessions from 23 species and 11 hybrids. The AFLP results were largely congruent with the results from previously examined nuclear DNA markers. Four distinct subgenera were identified within the genus Betula. These subgenera were partly in disagreement with the traditional (but disputed) division of the genus. In addition, the results indicated several groups of conspecific taxa. The majority of the species fell within subgenus Betula and shared a high degree of similarity with B. pendula. All hybrids were associated with this group, and the AFLP data contained signals on putative parents for some of the interspecific hybrids. Subgenus Chamaebetula and part of the Neurobetula species should be merged with Betula. The subgenera Betulenta, Betulaster, and the remaining part of Neurobetula are distinct and well supported. Although our results indicate that four major taxonomic groups can be recognized within the genus Betula, the relationship between them remains unclear. This may be due to the occurrence of hybridization and introgression, which would have a homogenizing effect on the relationships between species. Naturally occurring Betula species of hybrid origin may explain the low bootstrap values within the Betula clade. Electronic supplementary material  The online version of this article (doi:) contains supplementary material, which is available to authorized users.  相似文献   

9.
Fruit flies of the genus Bactrocera (Diptera: Tephritidae) are one of the major economically important insects in Asia and Australia. Little attention has been given to analyses of molecular phylogenetic relationships among Bactrocera subgenera. By using mitochondrial cytochrome oxidase I gene (COI) sequences, the phylogenetic relationships among four subgenera, Asiadacus, Bactrocera, Hemigymnodacus, and Zeugodacus, were investigated. Nucleotide diversity within subgenera ranged from 11.7 to 12.4%, and the net divergence among subgenera ranged from 11.2 to 15.7%. Phylogenetic trees calculated from both maximum parsimony and neighbor-joining phylogenetic analysis methods were highly congruent in terms of tree topologies. Phylogenetic analysis of mitochondrial COI sequences suggests that tephritid fruit fly species, which attack cucurbit plants, that is, Asiadacus, Hemigymnodacus and Zeugodacus, were more closely related to each other than to fruit fly species of the subgenus Bactrocera, which attack plants of numerous families. Our data supports previous classification of Bactrocera based on morphological characters. However, the phylogenetic tree showed the polyphyletic of fruit flies in subgenus Zeugodacus. Possible causes of speciation among fruit flies species in this genus were also discussed.  相似文献   

10.
11.
 The phylogeny of the genus Gunnera is investigated for the first time. Twelve species representing the six currently recognised subgenera are analysed. Two chloroplast DNA regions, the rbcL gene and the rps16 intron, together provide 46 informative characters out of 2335. A combined analysis of both genes gives four most parsimonious trees, firmly establishing the east South American G. herteri as sister group to the rest of the genus. The African G. perpensa is sister group to two well-supported clades, one including the South American subgenera Misandra and Panke, the other the Australian/New Zealand/Malayan species of subgenera Milligania and Pseudogunnera. Thus, South America is a composite area for Gunnera, showing up at two different levels in the cladogram. Our analysis supports a close biogeographic relationship between Australia and New Zealand. The evolution of some morphological characters is discussed. Lastly, the unusual structure of some of the rbcL sequences is reported. Received July 6, 2000 Accepted October 24, 2000  相似文献   

12.
《Systematic Entomology》2018,43(1):136-146
Phylogenetic analyses and species delimitation methods are powerful tools for understanding patterns of species diversity. Given the current biodiversity crisis, such approaches are invaluable for urgent assessment and delimitation of truthful species, particularly of endangered and morphologically cryptic taxa from vulnerable areas submitted to strong climate change and progressive human intervention such as the M editerranean region. In this study, we applied two DNA ‐based species delimitation methods and performed a B ayesian phylogenetic reconstruction using three mitochondrial gene fragments (12S , 16S and COI) to solve several taxonomic uncertainties among species of cross‐backed grasshoppers (genus Dociostaurus F ieber) from the western M editerranean. P hylogenetic analyses demonstrate the polyphyletic character of subgenera Dociostaurus , Kazakia B ey‐B ienko and Stauronotulus T arbinsky and, thus, the necessity of revising the currently accepted taxonomic subgenera within the genus Dociostaurus . We propose the split of closely related taxa with allopatric distributions such as D. (S.) kraussi and D. (S.) crassiusculus , considering the later a distinct species limited to the I berian P eninsula and excluding the name crassiusculus from other forms of D. (S.) kraussi from E ast E urope and A sia. Estimates of divergence times indicate that diversification of Dociostaurus probably happened during the M iocene–P liocene (3–7 Ma), and the split of the studied pairs of sister taxa took place during the middle and late P leistocene (1–2 Ma). This study highlights the need for more molecular studies on the genus and their different species for a better understanding of their evolution, genetic variation and population dynamics in order to prioritize strategies for their adequate conservation and management.  相似文献   

13.
To estimate the phylogenetic position of the strictly anamorphic genus Thysanophora among the class Ascomycetes sensu Kirk et al. and to examine the phylogenetic relationships among T. penicillioides and other Thysanophora species, 18S and 28S rDNA (D1 and D2 regions) sequences of 22 strains of four known and two unidentified Thysanophora species were determined and phylogenetically analyzed. The 18S rDNA analysis suggested that all Thysanophora species examined were members of Eurotiomycetidae, Eurotiales, Trichocomaceae. The 28S rDNA analysis indicated that these species were clustered together with Chromocleista, Eupenicillium, Geosmithia, and Penicillium assignable to three subgenera – Aspergilloides, Furcatum, and Penicillium. In the Eupenicillium lineage, a monophyly of T. penicillioides, T. longispora, T. taxi, T. canadensis, and T. cf. canadensis was supported by comparatively high bootstrap values. However, the ex-type strain and two strains of T. longispora isolated in Japan were of different phylogenetic positions. Thysanophora sp. was positioned at the base of the Thysanophora clade, although it was not supported by significant bootstrap values. From the results of this study, we consider that two anamorphic genera, Penicillium and Thysanophora, are clearly distinct in morphology but that they are not phylogenetically separable. Received: August 13, 2001 / Accepted: January 11, 2002  相似文献   

14.
The subgenera of Wiedemannia are poorly defined and, as such, most recently described species are not assigned to a subgenus or have been assigned to a subgenus without explanation. In this study we perform a molecular phylogenetic analysis to elucidate relationships within the genus Wiedemannia. We sequenced two mitochondrial (cytochrome oxidase c subunit I and cytochrome β) and two nuclear (carbomoylphosphate synthase domain of rudimentary and elongation factor‐1α) gene fragments to reconstruct phylogenetic relationships among the subgenera Chamaedipsia, Eucelidia, Philolutra, Pseudowiedemannia, Roederella and Wiedemannia (s.s.) using both Bayesian inference and maximum likelihood approaches. The genus was found to be monophyletic, but most of the subgenera were not. We propose eliminating the present subgeneric division altogether. Molecular dating using a log‐normal clock model and calibration with fossil species indicated that Wiedemannia diversified about 48 Ma, while there was still land connectivity between Europe and Asia with North America. Wiedemannia has a near‐worldwide distribution apart from the Australasian and Neotropical regions and Antarctica, with greatest species richness in the western Palaearctic, especially the Mediterranean region. Molecular phylogenetics support more recent morphological studies. The subgenera of Wiedemannia are invalid and rejected. Biogeographical data suggest potential hotspots, and the current distribution is discussed.  相似文献   

15.
Comparative ultrastructural investigations on many isolates ofTetraselmis from Japan and the Pacific coast of North America, and on cultures from the Culture Centre of Algae and Protozoa, Cambridge, England, have revealed that the species have characteristic fine structural features of the pyrenoid. Using the pyrenoid structure as a basic character it is proposed that the genus be subdivided into four subgenera,Tetraselmis, Prasinocladia, Tetrathele andParviselmis. In the present paper, species of the subgenusTetraselmis, includingT. cordiformis, T. ascus, T. convolutae andT. astigmatica sp. nov., are described in detail.  相似文献   

16.
17.
Pollen grains from ten species of Gunnera, chosen to represent the six different subgenera in the genus, were examined using light and scanning electron microscopy. The aim of the study was to explore characters that have the potential to define different types of pollen within Gunnera and to study the evolution of these characters in light of the phylogeny of the genus. According to our results, there are three main types of pollen in the examined species of Gunnera. Type 1, unique for the South American species G. herteri (subgenus Ostenigunnera), is characterised by an imperfect reticulum with sinuous undulating-creasted muri. A reticulum with equidimensional polygonal lumina is typical for the plesiomorphic type of pollen (type 2) present in subgenera Gunnera, Misandra and Panke. Lastly, pollen grains of subgenera Pseudogunnera and Milligania are characterised by a reticulum with lumina of variable shape and size (type 3). In G. macrophylla (subgenus Pseudogunnera), the lumina in the apocolpia are of a different shape and size from the lumina in the mesocolpia (type 3a), while in G. dentata, G. monoica and G. cordifolia (subgenus Milligania), the lumina are identical in the apocolpium and the mesocolpium (type 3b).

The identification of pollen types will possibly allow the interpretation of the different specimens of Tricolpites reticulatus, the fossil species believed to be allied to the extant Gunnera.

In addition to the revision on the pollen of Gunnera, a brief comparison between the pollen of this genus and its sister group Myrothamnus is reported.  相似文献   

18.
Chloroplast DNA (cpDNA) restriction site variation was examined in 32 species, representing five subgenera, of Bromus (Poaceae). Thirty-seven phylogenetically informative restriction sites were detected. Cladistic analysis of the restriction site data produced a single most-parsimonious tree of 50 steps. The cladogram indicated two major clades within the genus. One clade included B. trinii of subgenus Neobromus and species of subgenus Ceratochloa. The other was composed of subgenera Festucaria, Stenobromus, and Bromus. Within the second clade, species of subgenus Festucaria appeared in three lineages. The second clade also contained an assemblage of species belonging to subgenera Stenobromus and Bromus in a separate lineage. There was very little resolution of relationships in this assemblage since several species appeared individually in separate lineages. The cpDNA phylogenetic hypothesis did not separate species of subgenera Stenobromus and Bromus into well-defined clades as circumscribed by morphology and cytogenetics. The cpDNA tree is in agreement with the phylogenetic scheme based on traditional data in that: 1) subgenera Neobromus and Ceratochloa were the first to diverge, while Bromus and Stenobromus diverged later; 2) within the genus Bromus species with small chromosomes are ancestral; and 3) subgenera Bromus and Stenobromus probably originated from similar ancestors as Festucaria. The tree based on cpDNA data does not support that: 1) subgenera Neobromus and Ceratochloa did not have a common origin; 2) subgenus Festucaria is monophyletic; and 3) subgenera Stenobromus and Bromus are distinct entities. The mean nucleotide sequence divergence values between pairs of subgenera ranged from p = 0.0 to 0.9. These values suggest that cpDNA evolution in Bromus is slow.  相似文献   

19.
The bee tribe Eucerini is a large monophyletic taxon occurring in all continents, except Oceania and Antarctica, but far more diverse in the Americas and, especially, in the Neotropics. The phylogenetic relationships within its subtribe Eucerina, which contains the bulk of Eucerini diversity, is poorly understood, this being especially true for the relationships among its Neotropical representatives, which have been poorly represented in all phylogenetic studies, including Eucerini, to date. This leads to a generalized lack of confidence on the monophyly of the groups currently accepted as genera and subgenera. Here, a phylogenetic study based on three molecular markers (COI, 18S, and 28S, totalling about 1700 bp) and 58 morphological characters is presented as a contribution to the understanding of the relationships of the so‐called Thygater‐Trichocerapis group, and especially of the genus Thygater Holmberg, which has not previously been extensively sampled. Representatives of Trichocerapis, including its monotypic subgenus T. (Dithygater), are included for the first time in a phylogenetic study. The main results were: (i) support for the monophyly of the Thygater‐Trichocerapis group; (ii) support for the monophyly of Thygater; (iii) recognition of two main clades in Thygater, each one containing the type species of one of the previously recognized subgenera; and (iv) additional support for the position of Alloscirtetica as sister to all remaining Eucerina. Based on these results a redefinition of the scope of the two subgenera of Thygater is proposed, with changes in the subordination of three of its species, T. (Nectarodiaeta) chaetaspis comb.n. , T. (Nectarodiaeta) paranaensis comb.n. and T. (Thygater) mexicana comb.n.  相似文献   

20.
Aim The phylogeny of the enid land-snail genus Pachnodus was determined in order to provide information on biogeographical patterns within the granitic Seychelles islands. Location The genus Pachnodus is endemic to the granitic islands of Seychelles (Mahé, Silhouette, Praslin, La Digue and Fregate). Methods Phylogeny was determined using a cladistic analysis of nineteen shell and soft-body anatomy characters. The outgroup used was the central-east African genus Cerastus. Results The proposed phylogeny indicates that the genus divided into two distinct subgenera early in its history. Subsequent speciation occurred in parallel in the two subgenera, resulting in several islands supporting at least two distinct species representing the two subgenera. Main conclusions The pattern of speciation is largely explicable by vicariance as a result of sea-level rises, followed by habitat specialisation and further speciation. The pattern is in contrast to previously published scenarios for other taxa in the islands and indicates significant differences between evolutionary and habitat factors in the biogeography of the Seychelles fauna  相似文献   

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