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Asplenium cardiophyllum is a morphologically unusual species with simple leaves and anastomosing venation, and is often placed in the segregate genusBoniniella. To determine its systematic position, character comparisons were made of vascular anatomy, raphides in leaf epidermis, chromosome number and perispore of this species and those ofAsplenium sect.Hymenasplenium. Asplenium cardiophyllum conforms with sect.Hymenasplenium in its dorsiventral dictyostele, the presence of raphides, a chromosome number of 2n=156 (x=39), and lophate peristore with spinulate projections on the lumina. We therefore propose to includeA. cardiophyllum in that section. Dedicated to the memory of the late Professor Kunio Mitui.  相似文献   

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Summary By reinterpretation of the tooth formula ofOrnithorhynchus as dp/P M1–4 a synapomorphy with Marsupials has been discovered. Monotremes and Marsupials are sister groups, together derived from Theria of the Middle-Crelaceous.  相似文献   

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The Triassic marine reptiles at the base of the extinct Order Sauropterygia, traditionally known as nothosaurs, represent an unnatural assemblage of superficially similar forms. The traditional grouping of these animals has generally relied on the flawed basis of “primitive” characteristics whereas two distinct nothosaurian lineages can now be identified through the use of cladistic methodology. The Pachypleurosauria are the most plesiomorphic, but not the earliest, sauropterygians known. The Nothosauriformes include not only ‘nothosaurs’ but also the monophyletic group Plesiosauria and seemingly also the Placodontia. Rigorous coding of characters for the recently described nothosaurian genusSilvestrosaurus allows expansion of the phylogenetic data base for the Sauropterygia. The revised analysis reaffirms recent studies of relationship for the sauropterygians and demonstrates the affinity ofSilvestrosaurus with the Nothosauriformes. The explicit hierarchical classification scheme presented incorporates the hypothesized phylogenetic relationships of these long-misunderstood taxa. The traditional Suborder Nothosauria, now seen to be paraphyletic, must be abandoned.  相似文献   

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The phylogenetic position of Sophora inhambensis (one of only three species of Sophora that occur in Africa — the others are the widespread S. tomentosa and S. velutina) is inferred from an analysis of internal transcribed spacer (ITS) sequences for the core genistoid legumes. This species was thought to be closely related to the Podalyrieae based on chemical data (alkaloids and seed flavonoids), but molecular data indicates that it is strongly supported within the genus Sophora, close to the type species, S. tomentosa. Sophora velutina also groups with Sophora sensu stricto.  相似文献   

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Aspects of the life history ofKyllinga monocephala are described. Anther wall development corresponds to the Monocot type. The endothecium shows spiral thickenings. The tapetum is glandular and has uninucleate cells. Ubisch granules are present. Mature pollen grains (pseudomonads) are 3-celled at maturity. Ovules are bitegmic, crassinucellate and develop a funicular obturator. The embryo development conforms to theJuncus-variation of the Onagrad type. Endosperm, seed coat and pericarp are described.  相似文献   

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The mature seeds ofHampea nutricia are glabrous, ovoid, arillate and dark tan in colour. Longitudinal streaks on the seed surface correspond to the underlying integumentary vascular strands. Testa and tegmen are derived from the outer and inner integuments, respectively. The outer epidermis of the tegmen forms a palisade-like macrosclereid layer, the inner epidermis a fringe layer. The endosperm is single-layered and also fills the space between the two cotyledons. The embryo is nearly straight, gland-dotted; it has asymmetrical and folded cotyledons, and gossypol ducts. Systematic position ofHampea is discussed and its placement inMalvaceae is supported.  相似文献   

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Brathinus and Camioleum are assigned to positions within the Omaliinae (Staphylinidae). The male genitalia of Brathinus are figured for the first time, and a key is given to the known species.  相似文献   

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Opistocystidae ?ernosvitov, 1936 is a largely Neotropical oligochaete taxon containing seven species. Its familial status has never been formally challenged, although possible close relationships with Naididae and Phreodrilidae have been noted. Mitochondrial 12S and 16S rDNA, and nuclear 18S rDNA, of a range of aquatic oligochaete taxa, including Trieminentia corderoi (Opistocystidae), were analysed by Bayesian inference. This showed that T. corderoi is a derived lineage within Naididae, closely related to Pristina and its monotypic subfamily Pristininae. Opistocystidae as a whole (with its three genera, Opistocysta, Trieminentia, and Crustipellis) is thus likely to be a group within Naididae.  相似文献   

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The systematic position of the aberrant primulaceous genus Coris was investigated by means of cladistic analysis of nucleotide sequence data from the chloroplast gene rbcL . One new sequence ( Coris ) was added to a data matrix composed of a set of previously published sequences. The notion that Coris is most closely related to the Lythraceae is rejected, and very strong support for its position within the Primulaceae was found. The clariñcation of this issue is important for future analyses of phylogenetic interrelationships in the Primulales.  相似文献   

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Phaeocryptopus gaeumannii, causal agent of the Douglas-fir foliar disease Swiss needle cast, is the only known pathogenic species of the genus. Current classifications place Phaeocryptopus in the Venturiaceae (Pleosporales), typified by the apple-scab pathogen Venturia inaequalis. All core members of this family have hyphomycetous anamorphs. We sought to confirm these relationships by means of phylogenetic analyses of the small (SSU) and large (LSU) subunits and internal transcribed spacer (ITS) region of nuclear ribosomal gene sequences (nrDNA). Analyses indicated that both the genus Phaeocryptopus and the family Venturiaceae, as currently defined, are unnatural groups. Phaeocryptopus nudus, type of the genus, is aligned in the Dothioraceae (Dothideales) and P. gaeumannii in the Mycosphaerellaceae (Capnodiales) near species of Mycosphaerella and Rasutoria. Core representatives of Venturiaceae formed an unambiguous clade but ordinal placement was unresolved. The family apparently is not included in the Pleosporales, Dothideales, Myriangiales or Capnodiales. Coelomycetous Rhizosphaera form-species are accepted generally as anamorphic states of Phaeocryptopus, however the relationship never has been established conclusively. Species of Rhizosphaera are closely related to P. nudus but not to P. gaeumannii, supporting an anamorph-teleomorph connection between Rhizosphaera and Phaeocryptopus and providing further evidence that P. gaeumanii is not congeneric with P. nudus.  相似文献   

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Molecular phylogenies have associated Bataceae with Salvadoraceae and Koeberliniaceae in an expanded Brassicales. Despite a long taxonomic history, the knowledge of the flower of Batis is still fragmentary. The floral development of pistillate and staminate inflorescences of Batis maritima was investigated to understand homologies of floral structures and to discuss the phylogenetic position of Bataceae within the Brassicales. There has been considerable controversy in the past about the male flower, especially on the nature of the petals and the tubular structure enclosing the flower. Developmental evidence confirms that the male flower is built on a basic tetramerous bauplan and that the tubular structure is derived from four congenitally fused sepal lobes with the three anterior lobes highly reduced. The development of petals and stamens is unidirectional, and the androecium initiates the median stamens before the lateral stamens, suggesting the existence of two whorls. The pistillate flowers are reduced to the bare minimum with two transversal carpels enclosed by a bract. Partial inflorescences function as a swollen dispersal unit. The vestigial stipules probably represent colleters and are not homologous with true stipules. Several characters of Batis are reminiscent of the Brassicaceae, although a link with Salvadoraceae and Koeberliniaceae cannot be excluded.  相似文献   

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The Holarctic genus Catocala Schrank is argued to belong to an otherwise mainly Ethiopian and Oriental clade consisting, in addition to this genus, of Audea Walker, Crypsotidia Rothschild, Hypotacha Hampson, Tachosa Walker and Ulotrichopus Wallengren. The principal synapomorphy is a distinctively sclerotized, elongate ovipositor. A numerical phylogenetic analysis of this group based on fifty-five characters suggests that Catocala may be paraphyletic, a subset of species being the closest relatives of Ulotrichopus. Catocala and Ulotrichopus together appear to be the sister-group of the remaining four genera. Audea fatilega Felder & Rogenhofer is found to have the characters of Ulotrichopus.  相似文献   

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Several interpretations concerning the relationships of the Psilotaceae are discussed. The conclusion that the Psilotaceae are filicalean ferns is defended. New evidence which has appeared since earlier papers on the subject confirms this basic conclusion.  相似文献   

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An account is given of several aspects of the morphology of the genera Prionotylus Fieber and Centroplax Horváth. The systematic position of these genera within the family Coreidae and the generic assignment of Prionotylus meridianus Villiers are considered.  相似文献   

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