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1.
The phylogeny of the Forficulina, a suborder of the Dermaptera   总被引:2,自引:0,他引:2  
The phylogeny of the Forficulina (Dermaptera) has been reassessed, examining forty-eight species and thirty characters, of which thirteen characters of the thorax and wings are described or used for phylogenetic purposes for the first time, whereas the remaining seventeen have been extracted from literature. Examination of the thirty characters demonstrates that only twenty-three characters are useful for phylogenetic construction. The characters have been analysed with PAUP 3.1 yielding two equally parsimonious trees. The results suggest an exclusion of the 'Diplatyidae' (themselves paraphyletic) and the Karschiellidae from the Pygidicranidae and support the separation of the Apachyidae from the Labiduridae. A sister-group relationship of Anisolabididae and Spongiphoridae is not supported. The monophyly of the (Spongiphoridae (Forficulidae, Chelisochidae)) is supported.  相似文献   

2.
Ma J  Wang Y  O'Neill NR  Zhang XG 《Mycologia》2011,103(2):407-410
Lomaantha phragmitis sp. nov. is described and illustrated from a specimen collected on dead culms of Phragmites communis in southern China. The fungus differs from other described Lomaantha species in its conidiophores, conidiogenous cells and conidial appendages. Conidial morphology and presence or absence of percurrent proliferation of conidiogenous cells are the main characters distinguishing species within this genus. We provided a key and synoptic table of morphological characters of all three Lomaantha species.  相似文献   

3.
A near-complete, partially articulated skeleton of a hummingbird was recently found in the menilite shales of the Polish Flysh Carpathians. The specimen is dated to the Early Oligocene (Rupelian, approx. 31 Myr). It shares derived characters with extant hummingbirds and plesiomorphic characters with swifts. Its long, thin beak and short and stout humerus and ulna are typical for hummingbirds, but the coracoid resembles that observed in swifts. The osteology of the specimen is generally similar to that of the hummingbird described from the Early Tertiary of Germany but because it clearly differs in some characters from the German hummingbird Eurotrochilus inexpectatus, it is described as a new species of the same genus.  相似文献   

4.
5.
Michael Hesse   《Flora》2006,201(6):421-428
The ultrastructure of pollen walls in Araceae is characterized by the absence of a stable sporopollenin outer exine layer in subfamily Aroideae, and by the presence of several distinctive pollen characters typical for the other aroid subfamilies. This article discusses if and to which extent such distinctive pollen characters are mirrored in various classifications of Araceae, basing either on morphological or on molecular data. Accordingly, the pollen characters perfectly reflect the actual subfamily classification, and also recent arrangements of clades in trees basing on molecular data. The actual subfamilies appear no longer eurypalynous, but now strictly stenopalynous. Aside from the (settled) classification problem the fundamental question is addressed why do Aroideae lack an elaborated sporopollenin ektexine. Possible pollination biology benefits, deriving from an absence of an elaborated sporopollenin ektexine in Aroideae, are presented and discussed. Compared with all other subfamilies the most advanced and by far largest subfamily Aroideae has lost several crucial characters and simultaneously acquired corresponding opposed characters, amongst others a non-sporopollenin exine layer and an unusual thick and spongy endexine. Taken together, losses and acquisitions are interpreted as a major paradigm shift in Araceae evolution, which took place according to the fossil record probably in the Paleogene.  相似文献   

6.
Geographic variation was investigated in populations of the day gecko Phelsuma sundbergi from 22 islands in the Seychelles, using multivariate ordination procedures. Multiple group principal components analysis was used to negate ontogenetic variation. Seventy-eight characters from three character systems (body proportions, scalation and colour pattern) were analysed from 349 specimens. Three phenetic aggregations of granitic island populations were detected from the northwestern, northeastern and southern island groups. A comparison of the results from the three character systems analysed separately suggests that the separation of the southern form preceded that of the northern forms. Colour pattern characters reflect this closely, while body proportions and scalation characters follow evolution of body size. The populations of Phelsuma sundbergi on the coralline islands are not well differentiated from the races on the granitic islands, and probably represent recent colonizations or introductions by man.  相似文献   

7.
J R Wible 《Acta anatomica》1992,143(4):309-316
Four basicranial characters supporting a single origin of megachiropterans and microchiropterans have been identified by Wible and Novacek. King was not able to find two of these characters in specimens of the megachiropteran Pteropus and concluded that these characters be rejected in analyses of chiropteran phylogeny. To address King's claims, the two characters in question (regarding the tegmen tympani and ramus inferior of the stapedial artery) are documented here for Pteropus. The discrepancies between this report and King's appear to result from different criteria for identifying the tegmen tympani. Employed here are the criteria generally accepted by students of the mammalian chondrocranium.  相似文献   

8.
This paper studies the phylogenetic relationships of the nudibranch dorids that lack a radula. Numerous specimens belonging to 29 different species, representing all genera of this group and other related taxa, were examined anatomically. Details of the foregut were examined with SEM. From this anatomical study a total of 62 characters were considered. These characters have been polarized using the genus Berthella as the outgroup. Eight species of dorids with a radula and the genus Armina have been also included in the analysis for comparative purposes. The phylogeny obtained supports the hypothesis that the radula has been lost once in the Doridina and that the radula-less dorids are a monophyletic group. Cryptobranchia is monophyletic when the radula-less dorids are included. The new genus Mandelia , introduced on the basis of a new species from South Africa, is the sister group of the rest of the radula-less dorids, and is described as a new family, Mandeliidae. The radula-less dorids (currently placed in a separate superfamily) actually constitute an internal branch of other cryptobranch dorids. Phyllidia has no synapomorphies that distinguish if from Fryeria , which has one autoapomorphy, the ventral position of the anus. Therefore, both genera are regarded as synonyms. The evolution of several characters among the radula-less dorids is discussed, and the present phylogeny is compared with prior studies.  相似文献   

9.
An analysis of 13 taxonomic characters in a large population of the centipede, Scolopendra amazonica from Zaria, Northern Nigeria, is described. All show variation, some with age, others with sex, whilst those, such as spinulation, which do not exhibit such differences show considerable individual variation. Two important taxonomic characters, namely antennal segment number and the spinulation of the terminal legs, are shown to be affected by regeneration and are frequently regenerated in S. amazonica.
Comments are made on the value of these various characters and it is pointed out that the conclusions probably apply to other members of the Scolopendridae.  相似文献   

10.
Genetic variance in characters under natural selection in natural populations determines the way those populations respond to that selection. Whether populations show temporal and/or spatial constancy in patterns of genetic variance and covariance is regularly considered, as this will determine whether selection responses are constant over space and time. Much less often considered is whether characters show differing amounts of genetic variance over the life-history of individuals. Such age-specific variation, if present, has important potential consequences for the force of natural selection and for understanding the causes of variation in quantitative characters. Using data from a long-term study of the mute swan Cygnus olor, we report the partitioning of phenotypic variance in timing of breeding (subject to strong natural selection) into component parts over 12 different age classes. We show that the additive genetic variance and heritability of this trait are strongly age-dependent, with higher additive genetic variance present in young and, particularly, old birds, but little evidence of any genetic variance for birds of intermediate ages. These results demonstrate that age can have a very important influence on the components of variation of characters in natural populations, and consequently that separate age classes cannot be assumed to be equivalent, either with respect to their evolutionary potential or response.  相似文献   

11.
The 'Cichlasoma' facetum group is part of the taxonomically complex group of Neotropical cichlid fishes of the tribe Heroini. Many species groups and unplaced species of heroines are still left without a generic name following the revision of the genus Cichlasoma . We describe here the 'Cichlasoma' facetum group as a new genus, Australoheros , and provide evidence for its monophyly based on phylogenetic analyses of morphological and mtDNA characters. Australoheros is morphologically characterized by the lowest values in meristic characters among heroines and by three apomorphic characters in coloration pattern. In addition to the three described species of Australoheros , our results of species delimitation based on a combination of tree- and character-based approaches identify seven putatively new species of Australoheros . Several coding schemes of morphological characters are used to recover the intrageneric relationships within the genus, resulting in very similar topologies. Discovery of additional species within the genus is expected once material from the whole distribution area is studied.  相似文献   

12.
Abstract. The larva of Polynoncus seymourensis Mutchler is described from the Galapagos Archipelago, Ecuador. It is the first larva recorded of any species in the genus and has a suite of characters not found in the other trogid genera. Phylogenetic analysis of characters of larvae of all the genera supports the current phylogenetic system which was based on adults.  相似文献   

13.
Luque J  Martos S  Phillips AJ 《Mycologia》2005,97(5):1111-1121
Botryosphaeria viticola sp. nov., isolated from pruned canes of Vitis vinifera in NE Spain, is described and illustrated. Phylogenetic analysis based on ITS and EF1-alpha sequences and morphological characters of both anamorph and teleomorph confirmed this taxon to be included within the group of Botryosphaeria species with Dothiorella anamorphs. It is related most closely to B. sarmentorum and B. iberica from which it differs in morphological characters of the teleomorph and DNA sequences.  相似文献   

14.
The investigation of natural variability of metric morphological characters in frog gastrulation revealed that in genetically and environmentally homogeneous samples of embryos their variability is of a higher order of magnitude than that known for quantitative metric characters in adult organisms. Matching the coefficients of variation of characters under consideration to the specific rates of their changes in normal development revealed a strong positive correlation between the rates of morphological change and the amount of morphological variance. The increase in the variance is mainly in characters concerned with shaping of moving embryonic areas and arises as a result of a positive feedback between the movement of a given area and recruitment of cells from surrounding areas into the movement. The account of natural variation suggests a new model of amphibian gastrulation whose essential feature is the intimate connection between the movement and shaping of the dorsal blastopore lip of the gastrula.  相似文献   

15.
Eight lemma micromorphological characters of 83 taxa representing 61 genera in the Chloridoideae have been investigated using Scanning Electron Microscopy, including long cells, cork cells, stomata, bicellular microhairs, papillae, silica cells, microprickles, and macrohairs. Five new types of lemma micromorphological characters were reported here. Data for 27 taxa representing 19 genera from previous publications were also supplied to access the homology of lemma micromorphological characters for different groups through optimization onto a molecular cladogram. Given the optimization, five characters including long cells, cork cells, stomata, papillae, microprickles are of phylogenetic significance for supra-generic groups. Seven characters including straight outline long cells, crescent-shaped cork cells, absent stomata, absent papillae, dumb-bell-shaped silica cells, c-type microprickles, and papillate-base macrohairs may not be homologous, however, the enneapogonoid-type bicellular microhairs appeared as a synapomorphy for the Chloridoideae.  相似文献   

16.
The spontaneous rate of occurrence of two characters of malignant transformation was studied in mouse embryo fibroblasts C3H10T1/2, clone 8. This cell line, though "immortal" in vitro, is characterized by a normal phenotype in respect to many other properties. The spontaneous rate of occurrence of anchorage-independence (aga+) and dense foci on cell monolayer varied in different experiments from 0.65 X 10(-6) to 1.2 X 10(-6) and from 1.2 X 10(-6) to 3.6 X 10(-6) per cell per generation, respectively. The fluctuation test has shown that both characters occur as random spontaneous events. The altered colony morphology proved to be stable in all 28 foci of independent origin tested. In most cases, the morphological transformants were anchorage-independent. It is suggested that the occurrence of the characters studied is due to mutation in a gene with pleiotropic effect.  相似文献   

17.
We investigated the morphological relationships among eight populations of Sorex caecutiens/shinto group in East Asia using 11 cranial and dental characters and four external characters. Univariate and multivariate analyses of these characters failed to distinguish S. caecutiens and S. shinto. Morphological characters were, in fact, continuous between populations. Sorex shinto from Honshu was similar to S. caecutiens from the Korean peninsula and Primorye in skull dimensions and to S. caecutiens from Hokkaido-Sakhalin in external dimensions. Sorex caecutiens from Cheju Island is morphologically similar to S. shinto from Sado and Shikoku islands. These three insular populations were characterized by having large body sizes. Sorex caecutiens from Cheju was the largest of the S. caecutiens/shinto group in East Asia. This shrew from Cheju was classified definitively as S. caecutiens on DNA data, but has a unique morphology among S. caecutiens populations in East Asia. We therefore regard this Sorex shrew on Cheju Island as a new subspecies of S. caecutiens and designate it S. c. hallamontanus Abe and Oh.  相似文献   

18.
Ito  Tadayoshi  Nakagiri  Akira 《Mycoscience》1994,35(4):413-415
In the course of study of fungi from soil, a new genus and species,Stellatospora terricola, was isolated. The fungus is distinguished from other known genera in having star- or comfit-shaped ascospores with a distinct germ pore. The morphological characters of the genus are considered to resemble those of the Sordariaceae in Ascomycotina.  相似文献   

19.
A new paralichthyid flounder,Citharichthys gnathus, is described from 25 specimens from the Galapagos Islands. The new species strongly resemblesC. fragilis Gilbert, distributed in the Gulf of California and adjacent waters, in general appearance, and meristic and morphometric characters, but is distinguished from the latter by two adult characters, a remarkable bony knob at the anterior tip of the lower jaw and larger proportion of snout length in standard length.  相似文献   

20.
In recent years the hypothesis that pterosaurs were the major sister-group of dinosaurs and a closely-linked hypothesis that pterosaurs evolved flight from the ground up have gained general acceptance. A cladistic analysis of the Archosauromorpha using characters presented by previous workers results in a single most parsimonious tree with the Pterosauria as the major sister-group of the Dinosauria. However, that sister-group relationship is supported only by a suite of hindlimb characters that are correlated with bipedal digitigrade locomotion in dinosaurs. In pterosaurs the characters have been interpreted as correlates of bipedal cursorial locomotion, arboreal leaping, or involvement of the hindlimb in the wing. The homology of those characters in dinosaurs and pterosaurs cannot be supported. Reanalysis of the data after exclusion of those hindlimb characters results in most parsimonious trees with the Pterosauria as the sister-group of the Erythrosuchidae + Proterochampsidae + Euparkeria + Archosauria, in that order. This sister-group relationship is supported by a diverse assemblage of functionally independent skeletal characters from all regions of the skeleton. The results of the analysis cast doubt on the hypothesis that pterosaurs evolved flight from the ground up.  相似文献   

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