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2.
Paranourosorex remains from 14 Miocene and Pliocene localities in Inner Mongolia (China) and SW Siberia (Russia, Kazakhstan) are referred to a detailed biochronological sequence. The fossils are considered to represent a single evolutionary lineage which ranges in time from late middle Turolian (MN 12) through late early Ruscinian (MN 14). The lineage is subdivided into 5 species, including the previously described P. gigas Rzebik-Kowalska 1975 from Poland. Neomys inexspectatus Schlosser 1924 is assigned to Paranourosorex, and P. seletiensis n.sp. is described as new. All taxa are diagnosed. Evolutionary changes within the Paranourosorex lineage over a period of about 1.5 my are discussed. Intratribal comparisons suggest 3 anourosoricine clades during the Mio/Pliocene of Eurasia, consisting of 1) Crusafontina, 2) Paranourosorex, and 3) Anourosorex and Amblycoptus. 相似文献
3.
The paper presents the results of phytocoenological studies of the helophyte vegetation occupying the litoral zone of three North Italian glacial lakes and of the tall-forb communities occurring on the Adige riverside. It uses the method of the Zürich-Montpellier school. The association complex occupying the littoral zone of Lake Caldaro, above all the associations of Cladietum marisci, Caricetum elatae, Juncetum subnodulosi, Schoenetum nigricantis, and Selino-Molinietum caeruleae resembles those of ± mesotrophic, calcium rich prealpine lakes studied in Switzerland, West Germany and Austria. On the other hand, the majority of the communities occurring in the littoral of the great Lake Monticolo are of dystrophic-mesotrophic character, manifested above all in the occurrence of Caricetum diandrae, Peucedano-Caricetum lasiocarpae, and Caricetum elatae comaretosum, all with boreal distribution. The tall-forb association Lysimachio vulgaris-Filipenduletum has developed in the Adige riverside from Calthenion and/or from Magnocaricetalia communities as a result of interruption of mowing. 相似文献
4.
Gloeoheppiais re-established as a separate taxon; the genus differs from Heppiain apothecial development and thallus structure. Gloeoheppiaand the related genera GudeliaHenssen and PseudopeltulaHenssen described here are placed in the new family Gloeoheppiaceaein the Lichinales. In habit, the genera of Gloeoheppiaceaeresemble species of Heppiaand Peltula, whereas in apothecial development they correspond to some extent to the Lichinaceae. The species Gloeoheppia polysporaHenssen, Gloeoheppia rugosaHenssen, Pseudopeltula dicyanophoraHenssen, Pseudopeltula heppioidesHenssen, Pseudopeltula myriocarpaHenssen and Gudelia mexicanaHenssen, are described for the first time. In Gloeoheppiaceaethe thalli are ecorticate and the hyphae reticulately branched. The prototunicate asci contain eight, or up to 16, colourless and simple, occasionally two-celled spores. In species of Pseudopeltula, the apothecia are of a complex structure. The cyanobionts are small and single-celled; in P. dicyanophora‘internal cephalodia’ with an additional, filamentous cyanobiont are formed. Lectotypes are designated for Endocarpon turgidumAch. and Heppia furvaHue in Patouill. 相似文献
5.
The R-marbled ( R-mb) allele in maize confers a distinct pattern of anthocyanin pigmentation in the aleurone. We investigated the genetic mechanism involved in the formation and variability of this pattern. Wide variation was observed in the extent of anthocyanin pigmentation in marbled kernels. Progeny testing of different expressions resulted in distinct segregation profiles, indicating that the somatic variegation has a genetic basis. Drastic reduction in penetrance and expressivity was noticed when R-mb was transmitted in a single dose through the pollen parent. Analysis of the colored kernels from R-mb, including discordant endosperm-embryo phenotypes, showed that only germinal reversions from R-mb to R-sc (self-colored) were transmissible. Unlike other pattern alleles at the R locus, viz. R-stippled ( R-st) and R-Navajo ( R-nj), R-mb reverts to R-sc at a higher frequency. No dominance-recessiveness relation was found among the three pattern alleles. Reciprocal-cross differences occurred when R-mb was crossed with R-nj or R-st, but the interaction of R-mb with R-st was not entirely similar to that with R-nj. The characteristic variegation pattern due to R-mb is attributed to the action of a transposable genetic element on the basis of somatic and germinal instability, occurrence of discordant endosperm-embryo phenotypes, and genetic analysis of R-mb/R-st and R-mb/R-nj heterozygotes. The distinct genetic behaviour of R-mb, in comparison with R-st and R-nj, indicates specificity of the controlling element operating at this allele. 相似文献
6.
The genus Lepidauchen is discussed and defined. It is removed from the family Lepocreadiidae and placed in the family Acanthocolpidae based mainly on its possession of a uterine seminal receptacle. The type, and only valid species, L. stenostoma, is redescribed using material from Labrus merula from Corsica. Material from Coris julis and Symphodus tinca from the western Mediterranean off Marseille, L. merula from the western Mediterranean off Valencia, Diplodus annularis and Lithognathus mormyrus from the Adriatic Sea off Montenegro, and Archosargus unimaculatus from Venezuela was also examined. Other nominal species are discussed, but none are considered valid within this genus. 相似文献
7.
Biochemical characteristics and protein electrophoregrams of 22 strains of Enterobacter agglomerans, Erwinia herbicola, and Erwinia milletiae, including the type strains of these species, were found to be very similar. These strains constitute one of the numerous groups within the ‘ Erwinia herbicola-Enterobacter agglomerans complex’. Their classification in different genera or species is not supported by the results presented. These strains were isolated from different sources, such as clinical material, plants, or drinking water. It was stressed that further taxonomic studies should include isolates from a wide variety of ecological niches to improve the classification of bacteria belonging to the ‘ Erwinia herbicola-Enterobacter agglomerans complex’. 相似文献
8.
Flavonoid surveys of hydrolysed and direct leaf extracts of fifty two cocosoid palms revealed tricin, glycoflavones, proanthocyanidins, quercetin, flavonoid sulphates, isorhamnetin, and luteolin as regular constituents; present in 87, 77, 53, 47, 36, 26 and 26% of species, respectively. Kaempferol was found in 15% of the sample and apigenin in only one taxon of Attalea. Attalea and Syagrus were chemically heterogeneous groups. The flavonoid evidence suggested the removal of Polyandrocosus from the Allagoptera unit, the recognition of two Maximiliana species, the separation of Arecastrum and Arikuryroba from Syagrus and that Jubaea was closer to Butia than Jubaeopsis. Five morphologically similar Central American Scheelea species were distinguished by their flavonoid profiles. 相似文献
9.
Leaves from herbarium specimens representing 404 species and 89 sections of Old World and South American Astragalus were examined for nitro compounds. Thirty-three species contained nitro compounds. This included all species examined of section Uliginosi while sections Sewerzowia, Hemiphaca, Hemiphragmium, Oroboidei, Brachycarpus, Melanocercis, and Melilotopsis also contained significant percentages of nitro-containing species 相似文献
10.
Within Epilobium sect. Epilobium, a cytological analysis of 121 experimental hybrids, involving 40 species, indicates the presence of a widespread BB chromosome arrangement in Eurasia, Africa, and Australasia, as well as in North and South America less commonly. The AA chromosome arrangement, which differs from BB by one reciprocal translocation, occurs in North America, South America, and in at least three European species. The CC arrangement, which differs from AA by two reciprocal translocations, characterizes the Alpinae, a circumboreal group. Distinctive or only partly worked out chromosome arrangements occur in the European E. duriaei and E. nutans and in the North American E. luteum, E. obcordatum, E. oregonense, and E. rigidum. With earlier results, the chromosome arrangements of some 65 of the estimated 185 species of the section have been established fully or partly. 相似文献
11.
Two Colombian species described earlier by the authors under Prionosciadium, and a hitherto unnamed collection from the same country are systematically compared with North American Prionosciadium and the monotypic genera Cotopaxia (Ecuador) and Perissocoeleum (Colombia). Habit, foliage, inflorescence, fruit, and distribution all suggest that the páramo species exhibit considerable unity if Cotopaxia is excluded. It is indicated also that the genus Prionosciadium has been attributed to South America incorrectly. Despite the somewhat discordant evidence obtained from pollen morphology, it is concluded that the most feasible disposition of the four Colombian plants is to unite them under Perissocoeleum. 相似文献
12.
Abundant isolated remains of stylophoran echinoderms (cornutes and mitrates) are reported for the first time in the late Tremadocian ( Asaphellus Zone) Tumugol Formation of Korea. Mitrate remains include numerous adorals of Kirkocystidae. Several new important anatomical features have been observed on these adorals, as an internal calcitic layer that is associated to s 2 and possibly also to the palmar complex. This observation suggests that the palmar complex would be present not only in mitrocystitid mitrates, but also in peltocystitids. For the first time, several morphometric analyses have been undertaken based on isolated kirkocystid adorals, so as to explore the morphological diversity displayed by Korean adorals, but also in order to compare their morphology with that of other Gondwanan kirkocystids. Morphometric analyses indicate the occurrence of two contrasted morphologies within Korean adorals (morphotypes A and B), and of three distinct morphologies within European and North African forms (“ Anatifopsis”, “ Balanocystites”, and “ escandei” morphotypes). Comparison of Korean adorals with those from Europe and North Africa shows that: (1) morphotypes B and “ Anatifopsis” are equivalent; consequently, the two Korean specimens referred to morphotype B are assigned to the genus Anatifopsis; (2) morphology of most Korean adorals, which belong to morphotype A, is clearly distinct from that of all other described kirkocystids from Europe and North Africa. The small size, juvenile morphology, and great morphological variability observed in the morphotype A of the Korean adorals are suggestive of possible heterochronic processes (peramorphosis). 相似文献
13.
In North Africa, the ammonoids constitute an important part of the Devonian marine macro-invertebrates. New material has been recently collected in the ‘Argiles de Marhouma’ Formation from several sections located near Béni-Abbès in the Saoura Valley (Ougarta Mountains, Algerian Sahara). Red nodular limestones (i.e., ‘griotte’ facies) characterize this formation rich in ammonoids. The assemblages from the Ouarourout section are composed of Goniatitida and Clymeniida constituting 30 species and 19 genera belonging to 11 families, with Cyrtoclymenia, Erfoudites, Kosmoclymenia, Planitornoceras, Platyclymenia, and Prionoceras, as the most abundant genera. The taxonomic comparison and the biostratigraphic correlations are made by considering the assemblages recorded in the Anti-Atlas of Morocco, which are very close to those observed in Algeria. In the Ouarourout area, the ‘Argiles de Marhouma’ Formation contains middle and late Famennian ammonoid assemblages and three biostratigraphic intervals can be identified: Planitornoceras, Platyclymenia and Medioclymenia. 相似文献
16.
Capsicum as a spice crop, has wild and cultivated forms admired globally, including Indian subcontinent with vast climatic ranges. Systematic representation of the Indian Capsicum is required to address species relationships and sustainable agriculture, in face of unpredictable climatic conditions. We have updated the catalogue of Indian ‘C. annuum complex’ with 28 landraces and populations from different agro-climatic regions. The agro-climatic influence on the origin of stable chili landraces in India is remarkable, especially in the North East. The floral and fruit morphotype standards and chromosomal attributes have been considered for four distinct ‘C. annuum complex’ members under three species. The highlights of study are: (1) comparative profiling of Indian Capsicum species revealing less infraspecific variation within C. frutescens and C. chinense than C. annuum, at par with cultivation status, (2) karyotype analysis of some unique diploid landraces of C. annuum, (3) karyotypic confirmation of the polyploid Dalle Khursani landraces exclusive to India. To obtain more information, we attempted to correlate diversity of fruit and floral morphotype with chromosomal diversity. Existence of elite and rare germplasm found in the regional pockets offer great scope for enriching the agricultural tradition. The present dataset may serve as a template to be continuously upgraded by taxonomists, genomicists and breeders. 相似文献
17.
An early Lochkovian trilobite faunule from the Catavi Formation, Cochabamba Department, Bolivia, includes Paciphacops waisfeldae n. sp. and Kazachstania gerardoi n. sp. The latter species also occurs in the upper part of the Los Espejos Formation in the Precordillera of San Juan, Argentina, and the former is sister species to P. argentinus ( Thomas 1905) from the Los Espejos Formation. South American Paciphacops species are allied to North American, rather than Australian, congenerics. Kazachstania Maksimova 1972 appears to include some species previously assigned to Reussiana ?najdr 1987. Records of Paciphacops and Kazachstania provide evidence that earliest Devonian trilobites of Andean South America are largely geographically widespread taxa. 相似文献
18.
Samples of North American Pyrola asarifolia and its Asian vicariad, P. incarnata, were compared in morphology and leaf flavonol constituents. No qualitatively distinct attributes separate the plants from
these two regions. In addition, a broad overlap exists in the ranges of the 11 morphological characteristics examined. Both
Asian and North American plants exhibit some regional differentiation, but no simple clinal pattern is evident. Sepal width
is the only morphological characteristic that exhibits a bimodal tendency in sample means. Asian plants have significantly
narrower sepals compared with the North American samples. The chromatographic pattern of leaf flavonols in the Asian plants
is distinct from the North American because of the reduced number of compounds present and in having one large, highly concentrated
quercetin glycoside as the major constituent. The Asian vicariad is recognized as P. asarifolia Michaux subsp. incarnata (DC.) Haber & Takahashi, comb. nov. It is also considered to have a close affinity with the Eurasian P. rotundifolia. 相似文献
19.
A phylogenetic analysis of Panax was performed using restriction site variations of eight PCR-amplified chloroplast regions. Twenty populations were examined, representing 13 of the 14 species of Panax. Aralia cordata was used as the outgroup. The 11 restriction endonucleases produced a total of 105 restriction sites and length variations from the large single-copy region of cpDNA. Forty restriction variations are polymorphic. The cpDNA tree is largely congruent with the nuclear ribosomal ITS phylogeny. Similar to the ITS tree, the cpDNA dataset suggests the following relationships: (1) P. trifolius from eastern North America is sister to the clade consisting of all other Panax species; (2) P. ginseng and P. japonicus from eastern Asia form a clade with P. quinquefolius from eastern North America; (3) the Himalayan P. pseudoginseng is most closely related to P. stipuleanatus of southwestern China; and (4) the medicinally important P. notoginseng forms a clade with the closely related P. bipinnatifidus, P. ginseng, P. japonicus, P. major, P. quinquefolius, P. sinensis, P. wangianus, and P. zingiberensis. Two biogeographic disjunctions are detectable within Panax. One is the connection of the eastern North American P. trifolius with the rest of Panax species. The other is the more recent disjunction between the North American P. quinquefolius and the eastern Asian P. ginseng and P. japonicus. The active orogenies caused by the collision of the Indian Plate with Asia may have facilitated the diversification of Panax taxa in Asia in the late Tertiary. 相似文献
20.
A new species of Sorghastrum, S. pohlianum, from Mexico is described and illustrated. A numerical analysis comparing the new species to the closest species ( S. nutans and S. nudipes) was undertaken. The first three principal components explain 84% of the variation of the taxa involved. In addition there is morphological evidence to distinguish the new species from its closest relatives. It differs from S. nutans by showing smaller inflorescences, having sterile lemmas and anthers, and having somewhat smaller but wider blades and different flowering periods. In addition, it is distinguished from S. nudipes due to the presence of auricles > 1 mm long and inflorescence branches bearing spikelets along their entire length. 相似文献
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