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1.
Batra , Lekh R., and Richard P. Korf . (Cornell U., Ithaca, N. Y.) The species of Ciborinia pathogenic to herbaceous angiosperms. Amer. Jour. Bot. 46(6): 441–450. Illus. 1959.—On the basis of anatomical studies, 2 distinct species of Ciborinia, a generic segregate of Sclerotinia, are shown to occur on Erythronium. The life history and phytopathology of one of these, C. erythronii, are reported. The species is shown to be homothallic, to develop its sclerotia in nearly all parts of the plant, to overwinter also in the form of mycelium in bulbs, and to form spermatia in the field. Experiments on factors affecting formation of sclerotia and apothecia in the laboratory are reported. Prolonged washing of sclerotia formed in the laboratory proved to be an important factor for development of apothecia. A new species, C. trillii, pathogenic to Trillium is described, as is a new species, C. violae, pathogenic to Viola. The generic diagnosis of Ciborinia is emended on the basis of these studies. A new combination, C. hirtella, is also proposed.  相似文献   

2.
A phylogeny for Agelaius blackbirds was constructed using sequence data from an 890 base-pair (bp) region of the mitochondrial cytochrome-b gene in nine species of Agelaius and a single species from all but 1 of the 28 described blackbird genera and subgenera. The genus was found to be polyphyletic with the South American members of Agelaius more closely related to other South American blackbird genera. Application of bootstrap and jackknife manipulations supports this conclusion. That this relatively well-known genus is polyphyletic represents a warning to those attempting to construct phylogenies without first demonstrating monophyly of the ingroup. The conclusion that Agelaius is polyphyletic necessitates (1) the reinterpretation of previous studies that assumed monophyly and (2) the initiation of a variety of new comparative behavioral and ecological studies suggested by this finding.  相似文献   

3.
Graham, Alan. (U. Michigan, Ann Arbor.) Systematic revision of the Sucker Creek and Trout Creek Miocene floras of southeastern Oregon. Amer. Jour. Bot. 50(9): 921–936. Ilus. 1963.—The Sucker Creek flora is preserved in shales of volcanic origin exposed in Malheur County, southeastern Oregon. A study of the flora has been made and the systematic revisions presented. The following new species are described: Osmunda claytonites, Davallia solidités, Shepherdia argen∗∗∗teaites, Magnolia ovulata, Anoda suckerensis, and Platanus youngii. A new combination, Hiraea knowltoni (Berry), is proposed. Additional synonymies, Incertae Sedis, and other taxonomic changes are included. The Trout Creek flora is to the west of Sucker Creek in Harney County, southeastern Oregon. The fossils are preserved in diatomite. Four new species are described: Equisetum miocenicum, Gossypium arnoldii, Urena miocenica, and Spiraea miocenica. New combinations are Pteridium calabazensis (Dorf), and Nymphaea rotunda (Arnold). A revised species list is given for the 2 floras. The Sucker Creek flora contains 47 families, 60 genera, and 69 species, presently identified. The Trout Creek flora contains 29 families, 51 genera, and 75 species. The distributional, ecologic, and geologic interpretations of the 2 floras will be presented in a subsequent publication.  相似文献   

4.
A new species of Predaea (Gigartinales, Rhodophyta) is described from Hawaii. It is compared in important morphological details with other species of the genus, all of which are distributed in the subtropics. Predaea is likewise compared to the genera of Nemastomataceae, and should be included in that family. The genus Yadranella Ercegovic (Nemaliales, Rhodophyta) is placed in synonymy with Predaea.  相似文献   

5.
Remains of the fossil Marattiales are very rare in Lower Pennsylvanian sediments. The present report describes a new species of the fertile fern foliage Scolecopteris from the Lewis Creek, Kentucky locality (Lower or lower Middle Pennsylvanian). Scolecopteris conicaulis n. sp. has radial synangia composed of a ring of 4–7 elongate, exannulate sporangia. Most features of the synangia of S. conicaulis were previously hypothesized to be primitive in Scolecopteris based on geologically younger species. Supposed primitive characters include the large synangium pedicel with fiber core, an outer-facing sporangial wall lacking differentiation or zonation, and large spores. The anatomy of the sporangium walls, pinnule morphology, and general spore type support an association with the Minor group of Scolecopteris. The new species is similar in several important features to Scolecopteris (Cyathotrachus) altus, the only other anatomically preserved fertile marattialean known from this early time, and indicates a considerably earlier origin for fertile foliage of this type.  相似文献   

6.
A collection of anatomically preserved conifer cones from the Early Cretaceous of Virginia contains two new species of the extinct pinaceous genus Pityostrobus. Superficially, the fossil cones resemble those of modern species of Picea. However, the fossils reveal such a peculiar mixture of anatomical features that they cannot be assigned to any extant genus of the Pinaceae. One of the new species, Pityostrobus hueberi, is most comparable with Pityostrobus corneti Alvin from the Early Cretaceous of Belgium. Pityostrobus virginiana, the other new species, differs from all other members of the genus in only slight—but nonetheless significant—attributes. Pityostrobus hueberi and P. virginiana are the first species of this genus to be reported from Early Cretaceous sediments of the North American Atlantic Coastal Plain. As such, they increase our knowledge of the structural variation exhibited by ancient members of the Pinaceae.  相似文献   

7.
Termitaria snyderi Thaxter is found in and around Gainesville, Florida, infecting the subterranean termites Reticulitermes virginicus (Banks) and R. flavipes (Kollar). The fungus forms sporodochia-like structures on the exoskeleton of the termites. These structures have a subhymenium of tightly held phialides. The phialides cut off phialoconidia apically in basipetal succession into the collarettes at conidiogenous loci. The basal layer of the thallus has certain thick-walled cells that send haustoria into the integument of the host termite. Termitaria appears to be closely related to another cuticle-infecting parasite of termites, Mattirolella Colla. A new species of the latter, M. crustosa, is described here. The relationships of the two genera are discussed and a new order of Deuteromycetes, Termitariales is proposed for them.  相似文献   

8.
Pericarps generally are thought of as structures having determinate growth, serving as a protective covering for the developing gonimoblast. In laboratory culture, the pericarps of Champia parvula (C. Agardh) Harvey, Lomentaria baileyana (Harvey) Farlow and Lomentaria sp. exhibited indeterminate growth. These tissues could be excised and grown as separate female plants. The new plants were indistinguishable from the parent tissue, were fertile, and produced viable carpospores.  相似文献   

9.
Telangium pygmaeum Graham is known from Upper Pennsylvanian coal balls from the Calhoun coal mine (Illinois). The species was described as possessing radial synangia consisting of 3-5 sporangia fused laterally for about f13 their length. Synangia were believed to be sessile and borne terminally or laterally on a branching rachis without lamina. Examination of new coal ball material of the same age indicates that the synangia are borne abaxially on the pinnules of a compound frond with the anatomy of a Psaronius leaf (Marattiales). Synangia are sessile and borne in two rows, one on either side of the pinnule midrib, under the unbranched lateral veins. Synangia are radial, 0.6 mm in diam, and consist of a ring of thin-walled sporangia fused to near their apices prior to dehiscence, but separating on dehiscence to release spores along their inner midline. Spores are spherical, trilete, 30-48 μm in diam, with a granulate ornamentation. The new genus Araiangium is proposed for this material based on the organization of the sessile thin-walled synangia. Araiangium is compared with other marattialean genera with sessile synangia (Acaulangium, Acitheca), and with the pedicellate synangia of various species of Scolecopteris. Criteria used in the delimitation of genera in Paleozoic anatomically preserved marattialean fertile foliage are discussed.  相似文献   

10.
Three new species of Protostelium (Order Protostelida of the Mycetozoa) are described: P. irregularis, P. zonatura, and P. pyriformis, all with rather wide distribution and occurring on dead attached plant parts, less often in soil and humus. The latter two species differ from the first and from the other two known species, P. mycophaga Olive and Stoianovitch and P. arachisporum Olive, in the endogenous origin of the stalk. P. mycophaga var. crassipes, with vesicular stalk bases, is the third variety of that species to be described. A key to the genus is included.  相似文献   

11.
陈桂清  黄河 《菌物学报》1988,7(Z1):53-60
对于共头霉的唯一已知种总状共头霉Syncephalastrum racemosum Cohn ex Schroet.(S 1)和新发现的具单孢孢子囊的新种单孢共头霉下的三个变种,原变种S.monosporum Zheng et al. var. monosporum( S7, S8, S9),冠囊变种var. cristatum Zheng et al. (S10, S11)及多重生变种var. pluriproliferum Zheng et al.(S12) 6株菌的蛋白和酯酶进行了聚丙烯酰胺凝胶电泳的研究.这4个分类群的蛋白图谱和酯酶酶谱互不相同,而同一分类群内各个菌株之间则有很高的相似性.从计算出的相似性百分数来看,3个新变种相互之间有较为密切的关系,而和S. racemosum虽然较疏远,但也有相当程度的亲缘关系.这些结果被认为支持了根据形态鉴定而定这三个新变种属于同一新种内并将其和S. racemosum一并归属于一个属内.由此可见,聚丙烯酰胺凝胶电泳是共头霉分类的有用的辅助手段.  相似文献   

12.
The genus Kermadecia (Proteaceae), originally described as endemic to New Caledonia, has been expanded in recent decades to include three species from the New Hebrides and Fiji. Specialists on the Proteaceae have suggested that the three Melanesian species were generically misplaced, and careful reexamination supports this viewpoint. It is now apparent that a distinct group within the subfamily Grevilleoideae is composed of the genera Euplassa (endemic to South America), Sleumerodendron (a monotypic New Caledonian genus), Gevuina (based on a single South American species but recently expanded to include two other species from Queensland and New Guinea), and the three questionable Melanesian species. A review of this cluster of taxa indicates that Gevuina should again be interpreted as restricted to South America and that the generic name Bleasdalea F. v. Muell. ex Domin should be adopted for a group of five species extending from Queensland and New Guinea to the New Hebrides and Fiji. The relationships of the four genera are discussed and within Bleasdalea four new combinations are proposed: B. bleasdalei (F. v. Muell.), B. ferruginea (A. C. Sm.), B. vitiensis (Turrill), and B. lutea (Guillaumin). Kermadecia, very distinct from the four genera under present consideration, is again interpreted as a New Caledonian endemic.  相似文献   

13.
Abstract Phylogenetic analysis of Saltusaphidinae (Homoptera: Aphidoidea: Drepanosiphidae) was made by using 10 generic, 17 adult and 2 embryo characters. The results suggest alternative hypotheses: (1) Allaphis should be a subgenus of Thripsaphis; (2) Peltaphis should be an independent genus; (3) Stenaphis should be a subgenus of Subsaltusaphis; (4) monophyly of Sminthuraphis; and (5) phylogenetic relationships of Neveskyella, Subsaltusaphis, Saltusaphis and Iziphya. In order to resolve the argued position of Macropodaphis Remaudiere and Davatchi, 1958, Phyllaphidinae, Saltusaphidinae and Macropodaphis were taken as in-group members, 6 morphological characters and host-plant character were used. The result shows that Macropodaphis should be in a new subfamily Macropodaphidinae, and Macropodaphidinae and Saltusaphidinae should be sister groups.  相似文献   

14.
Three new dinoflagellate species, Karenia papilionacea sp. nov., Karenia selliformis sp. nov., and Karenia bidigitata sp. nov., were compared with the toxic species Karenia mikimotoi (Miyake & Kominami ex Oda) G. Hansen & Moestrup, Karenia brevis (Davis) G. Hansen & Moestrup, and Karenia brevisulcata (Chang) G. Hansen & Moestrup using the same fixative. Distinguishing morphological characters for the genus Karenia included a smooth theca and a linear apical groove. The new species can be distinguished on the basis of morphological characters of vegetative cells that include the location and shape of the nucleus; the relative excavation of the hypotheca; the characteristics of apical and sulcal groove extensions on the epitheca; the cellular shape, size, and symmetry; the degree of dorsoventral compression; and the presence of an apical protrusion or carina. Species with pronounced dorsoventral compression swim in a distinctive fluttering motion. An intercingular tubular structure traversing the proximal and distal ends of the cingulum is common to the species of Karenia, Karlodinium micrum (Leadbeater & Dodge) J. Larsen, Gymnodinium pulchellum J. Larsen, and Gyrodinium corsicum Paulmier. Molecular phylogenetic analyses of rDNA sequence alignments show that the new species are phylogenetically distinct but closely related to K. mikimotoi and K. brevis.  相似文献   

15.
A new species of the diatom genus Eunotia is described. The species, E. catillifera Morrow, is distinguished by the presence of fin-like plates, or transapical ridges, which alternate with the striae on the valve faces. This alga appears to be intermediate between the more typical Eunotia species and Semiorbis Patr. This observation suggests that Semiorbis hemicyclus (Ehr.) Patr. in Patrick and Reimer be returned to Eunotia hemicyclus Ralfs in Pritchard and that the use of the generic name Semiorbis be discontinued.  相似文献   

16.
Joel  Cracraft 《Ibis》1971,113(2):229-233
A new fossil genus and species, Onychopteryx simpsoni, is described for a proximal end of a tarsometatarsus from the lower Eocene (Casamayor Formation) of Argentina. Onychopteryx is considered most closely related to the Opisthocomidae but is sufficiently distinct to be placed in its own family, the Onychopterygidae. Onychopteryx indicates that the Opisthocomiformes had differentiated by the early Eocene and were present in South America at that time.  相似文献   

17.
18.
Several silicified ovulate cones from the late middle Miocene (Barstovian) represent a new species, Picea wolfei Crabtree. This is the second species of Picea for which structurally preserved seed cones are known to be reported from the Tertiary. The cones are 5.0–8.0 cm long and 1.5–2.0 cm at their greatest diameter. Ovuliferous scales are inserted helically around the cone axis and are recurved at their point of divergence. Each scale is broadly obovate to spatulate with a rounded apex and bore two seeds adaxially. The bract subtending the scale is 4.5–7.3 mm long and is fused to the scale for 1.4–2.0 mm. Each bract has an inflated keel-like base which projects abaxially between the seeds of adjacent scales. The fossil cones superficially resemble those of the extant Picea breweriana, yet differ from them anatomically. The new species also resembles Picea lahontense, a fossil compression from the Miocene Trout Creek Flora of south-central Oregon, but the different modes of preservation preclude meaningful comparison. Picea diettertiana, the only structurally preserved fossil cone of this genus previously described, is quite dissimilar in that it lacks a sclerotic pith.  相似文献   

19.
DNA containing structures (nucleoids) were visualized by 4′, 6-diamidino-2-phenylindole (DAPI) fluorescent staining in two groups of cyanophytes (59 filamentous oscillatorialean species and 12 coccal Synechococcus-like organisms) to test the possibility of using nucleoid morphology in cyanophyte taxonomy. The morphology of nucleoids (size, shape, and structure) in oscillatorialean species is specific for individual families. The morphology of the nucleoid in Synechococcus-like species agrees from the proposed separation of the genus Cyanothece from Synechococcus. A much different nucleoid morphology in three species of Cyanothece suggests that these species should be separated into a new genus. On the basis of other characters, the species could be returned to the genus Cyanobacterium. My results indicate that the morphology of nucleoids is a valuable character in the classification of the cyanophytes examined; thus, it is a prospective feature that could be used in the taxonomy of other groups of cyanophytes. Additionally, DAPI staining is not a complicated procedure. The new character is easy to see in samples taken from nature, both living and preserved.  相似文献   

20.
Forests of the subtropical and tropical regions of North America harbor cellular slime molds not found in the soils of temperate deciduous forests investigated previously. However, most species found in the temperate forest are common in the tropics. Although the diversity of forms is greater in the soils of tropical forests the numbers of Acrasieae per unit of soil are comparable. Characteristic of tropical and subtropical forest soils are Acrasieae bearing crampon bases, of which four new species of Dictyostelium are presently known. Also present, but less frequently isolated, are two other new species of the genus Dictyostelium and two still undescribed species of the Guttulinaceae. Occasional isolates of D. purpureum and D. discoideum were found that produce macrocysts, which seem, also, to be confined to tropical and subtropical areas. Macro-cysts were previously known only in D. mucoroides and D. minutum isolated from temperate forest soils. The occurrence and distribution of Acrasieae in warm temperate desert and mesquite-scrub, in subtropical hammock, and in tropical thorn, deciduous, seasonal evergreen, rain, and cloud forests were investigated. Acrasieae were well represented in all of these forests except desert. The number of species and the total populations were largest in seasonal evergreen forests. The composition of the cellular slime mold populations and the dominant species within these populations could be related to the soil environment as expressed by the dominant vegetation.  相似文献   

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